Reference · Dock provenance
There is no national dock code. Here is what we size to instead.
A deck has the IRC and the AWC DCA 6 span tables — one document, one edition, one page number per value. A dock has nothing of the kind. So instead of a code citation, this page gives you the whole chain: who can tell you no, what a marina engineer designs to, what the float catalogs actually publish, and the four numbers in our engine that have no published source at all.
It exists for the same reason the deck code page does. The useful question about an estimator is not what number it gave you — it is where that number came from, and what it does at the edge. Everything below was retrieved live — the anchor documents on 2026-08-13, the float-drum ratings on 2026-09-27, and the dead-load weights on 2026-09-27 and 2026-09-28; pull the same files and check us.
The authority ladder
Every dock claim sits on one of three rungs, and mixing them is how dock software ends up sounding authoritative about nothing.
Tier 1 — legal force
Who can tell you no
Three offices decide what you are allowed to build before any engineering starts: your U.S. Army Corps district, your state waterway agency, and local shoreline zoning. They set width, footprint and how far out you may go.
Their caps shape the dock before a single member is sized — Wisconsin exempts piers up to 6 ft wide with one loading platform of up to 200 sq ft, and Washington holds residential piers and docks to 6 ft for the first 30 ft from mean low water and approves float grounding only in reservoirs at drawdown. Tell the estimator which state and which water, and it checks your dock against the caps we have verified against the agency’s own document, naming the office behind each one. Where we hold no rules for your water it says that instead of guessing. We never tell you that you are permitted; that is the agency’s word, not ours.
USACE Section 10 / 404 · State waterway agency · Local shoreline zoning
Tier 2 — published guideline
What a marina engineer designs to
The closest things docks have to a published design standard are two public documents: the Defense Department’s UFC 4-152-07 small-craft berthing criteria and California Boating & Waterways’ 2005 marina guidelines — sections you can look up, cite and check us against.
Guidelines, not law — a Defense Department criteria document and a California marina document, read as best available practice on a lake in Minnesota. Where our sizing keys to one we name the section, so you can pull the same PDF and read the same line. ASCE MOP 50 is the marine-PE standard of practice, but it is paywalled: we cite it as what an engineer designs to, never for a number we have not verified ourselves.
UFC 4-152-07 §6-3.3.2 — 2 in reserve · CA DBW 2005 §C2.2 — 25 psf live · CA DBW 2005 §F2.9 — 3:1 gangway
Tier 3 — documented practice
What the float catalogs actually publish
Flotation, minimum water depth and pipe-dock limits come from manufacturers who publish their method — named suppliers, published numbers, documented practice.
Manufacturer practice carries no legal force and we never let it wear language that implies it does. It also carries a caveat most software ignores: catalog buoyancy ratings are measured at 100% submersion — a “500 lb” drum delivers 500 lb only when the dock is awash — so the rating is credited at design submergence, never at face value.
Dock Builders Supply — 28–35 psf · EZ Dock — 2–3 ft minimum depth · DockinaBox — pipe docks under 8 ft
Who governs your water
These caps decide the dock’s width and footprint before any engineering starts. 6 of the rows below are wired into the estimator: tell it the state and the kind of water and it checks your dock against that authority’s numbers and names the office behind them. The other two are reference — federal Corps authorization applies everywhere, and the submerged-vegetation guidelines apply by habitat, so neither can be selected from a state.
| Where | The rule | Document |
|---|---|---|
| Federal — navigable watersU.S. Army Corps of EngineersReference only | Structures in navigable water need Corps authorization. The 2026 Nationwide Permits run 2026-03-15 to 2031-03-15; NWP 2 covers structures in artificial canals within residential developments, so most new residential docks ride a district Regional General Permit or an individual Section 10 permit instead. | 2026 NWP reissuance, 91 FR 768–886 (2026-01-08) |
| WisconsinWisconsin DNRChecked by the estimator, in part | An exempt pier is no more than 6 ft wide, with one loading platform wider than 6 ft of up to 200 sq ft; extends no farther than the 3 ft depth at summer low water or the depth needed to moor, whichever is farther; has no more than 2 boat slips for the first 50 ft of shoreline and one more for each additional 50 ft; and sits outside an area of special natural resource interest without interfering with other riparian owners’ rights.Not checked, because we do not hold the data: reach against the 3 ft summer-low or mooring depth; boat slips against 2 for the first 50 ft of shoreline and one more per additional 50 ft, under 30.12(1g)(f)1.c; whether the site is in an area of special natural resource interest, and interference with other riparian owners’ rights, under 30.12(1g). | Wis. Stat. 30.12(1g)(f) |
| MinnesotaMinnesota DNRChecked by the estimator, in part | No permit is needed where the dock is not more than 8 ft wide and not combined with other similar structures, is no longer than its use needs (including reaching navigable water depths), allows the free flow of water beneath it, and meets the rule’s other conditions.Not checked, because we do not hold the data: length against what the dock’s use needs, including reaching navigable depth; free flow of water beneath it; the rule’s other conditions (combined structures, navigation, marina use, local land use controls). | Minn. R. 6115.0210 subp. 4(A) |
| Washington (fresh water)Washington Department of Fish and WildlifeChecked by the estimator, in part | Residential piers and docks are held to 6 ft wide for the first 30 ft from the shoreline, measured from mean low water (50 ft on the Columbia River); ramps to 4 ft, fully grated; decks and floats at least 30% or 50% grated; the pier underside at least 1.5 ft above the ordinary high water line; floats kept off juvenile salmonid rearing areas, with grounding of floats approved in reservoirs and impoundments only when the water level is dropped.Not checked, because we do not hold the data: where mean low water lies; grating; the pier underside against 1.5 ft above the ordinary high water line; whether floats ground out or sit over juvenile salmonid rearing areas; the Columbia River’s 50 ft window and 20 ft of water beneath docks. | WAC 220-660-140 |
| FloridaFlorida DEPChecked by the estimator, in part | Under 403.813(1)(b), a private dock is exempt up to 500 sq ft of over-water surface area in Outstanding Florida Waters and 1,000 sq ft elsewhere if it is the sole exempt dock along 65 ft of shoreline, sits on pilings or floats with no filling or dredging beyond installing the pilings, does not substantially impede the flow of water or create a navigational hazard, and is used for recreational, noncommercial activities. Under 403.813(1)(i), a private dock of up to 1,000 sq ft of over-water surface area in an artificially created waterway is exempt “when such construction will not violate existing water quality standards, impede navigation, or affect flood control.”Not checked, because we do not hold the data: whether this is Outstanding Florida Waters or an artificially created waterway; one exempt dock per 65 ft of shoreline (403.813(1)(b)5); filling or dredging beyond installing the pilings, under 403.813(1)(b)2; whether the dock substantially impedes the flow of water or creates a navigational hazard, under 403.813(1)(b)3; recreational, noncommercial use, under 403.813(1)(b)4; in an artificially created waterway, whether the dock will violate existing water quality standards, impede navigation, or affect flood control, under 403.813(1)(i); permission to use state-owned or water management district lands, under 403.813(1). | Fla. Stat. 403.813(1)(b) and (1)(i) |
| New York (tidal waters)NYSDECChecked by the estimator, in part | One open-pile catwalk or dock no greater than 4 ft wide is a generally compatible use which requires a permit; wider, or floating docks totalling 200 sq ft or more, are presumptively incompatible over vegetated tidal wetland and need a permit elsewhere (items 14–17). DFW-6 guidance: residential docks generally no wider than 4 ft, and no more than 25% of the width of the waterway.Not checked, because we do not hold the data: the wetland category, which decides the permit class; 25% of the width of the waterway; one open-pile catwalk or dock per principal building. | 6 NYCRR 661.5(b) |
| TVA reservoirsTennessee Valley AuthorityChecked by the estimator, in part | Docks fit a 1,000 sq ft rectangle at the lakeward end of the access walkway (1,800 sq ft in an area of preexisting development); access walkways are not counted and are no wider than 6 ft; no more than 150 ft from the shoreline or one-third of the way to the opposite shore; fixed decks 18 to 24 in above full summer pool by reservoir; 50 ft from the neighbors’ docks in subdivisions recorded after November 1, 1999.Not checked, because we do not hold the data: whether this is an area of preexisting development; one-third of the distance to the opposite shoreline; which reservoir this is, and its full summer pool; 50 ft from the neighbors’ docks in subdivisions recorded after November 1, 1999. | 18 CFR 1304.204 |
| Florida — seagrass, marsh, mangroveUSACE / NMFS (Jacksonville District)Reference only | Walkway 4 ft maximum over submerged vegetation, decking at least 5 ft above mean high water, terminal platform 160 sq ft grated or 120 sq ft planked, pilings at least 10 ft on center. | USACE/NMFS dock construction guidelines (Aug 2001, rev. 2008) |
The structural constants, and their status
The 18 structural constants below are the ones a reader most often checks. 11 are sourced to a published document, 3 are partial, and 4 have no published source at all — those are labelled Gap here and trade practice on the line item in your takeoff, and the engine’s own code marks them for engineering review.
The table is not every number the engine holds. The per-unit hardware counts — bolts per drum, per cleat, per frame stringer (wood frames) and per pile, a bracket per pipe leg, a hinge set per gangway, screws per board crossing — have no published source either, and each says trade practice on its own line item.
| What it decides | Value | Status | Source |
|---|---|---|---|
| Uniform live load — residential basis (default) | 20 psf | SourcedTier 2 | Ameren Lake of the Ozarks Permit Requirements, Appendix B §7.7.1, permit-mandated on that lake only |
| Uniform live load — marina basis | 25 psf | SourcedTier 2 | CA DBW, Layout and Design Guidelines for Marina Berthing Facilities, 2005, §C2.2 |
| Gangway live load — residential basis | 30 psf | SourcedTier 2 | Ameren Lake of the Ozarks Permit Requirements, Appendix B §7.9, residential, permit-mandated on that lake only — the rating a catalog gangway is procured to |
| Gangway live load — marina basis | 100 psf | SourcedTier 2 | CA DBW, Layout and Design Guidelines for Marina Berthing Facilities, 2005, §F2.2 — the rating a catalog gangway is procured to |
| Reserve buoyancy at dead + full live load | 2 in above water | SourcedTier 2 | UFC 4-152-07 §6-3.3.2 — min 2 in freeboard to the pontoon top |
| Float drum buoyancy (24"×48"×16") | 500 lb | SourcedTier 3 | Published full-submersion ratings for 24"×48"×16" drums run 526–598 lb: Formex FF 2416-FM 526, Formex FF 2416-TM 580 and Eagle Floats 2 x 4 x 16 530, each maker stating the condition on its own page, and PermaFloat BD2448-16 598, listed by the dealer BARR Plastics under a fully-submerged heading. We hold 500 as the round conservative figure below each of them. Eagle Floats 2x4x16F, a flange float, publishes 480 lb — below 500 — so the dock catalog does not offer it. |
| How deep the drums may ride under dead load | 45% submerged | SourcedTier 3 | Dock Builders Supply — design near 40% submergence, never past 50%; 45% is the middle of the two |
| Minimum total flotation — residential / marina | 28 / 40 psf | SourcedTier 3 | Residential: Dock Builders Supply publishes 28–35 psf residential totals, and 28 is the floor of that band; American Muscle Docks aims for about 30 psf on a wood-framed, wood-decked dock. Marina: American Muscle Docks — "A marina expecting more than a few people needs about 40 lbs. per square foot." |
| Shallowest low water a floating dock is sized for | 2.5 ft | SourcedTier 3 | EZ Dock — 2–3 ft minimum. Tier-1 rationale: Washington approves float grounding only in reservoirs and impoundments when the water level is dropped (WAC 220-660-140(3)(c)(ii)). |
| Gangway slope, run to rise | 3:1 (strict arm only) | PartialTier 2 | CA DBW 2005 §F2.9.1/.2 — the 2½:1 relaxation needs a tidal datum or exceedance duration we do not have. With the shore end at the float's high-water deck level, 3:1 asks about 3.2 ft of gangway per foot of water-level travel. |
| Spacing between pile bents | 10 ft o.c. | PartialTier 1 | USACE/NMFS dock guidance sets 10 ft on center as an environmental MINIMUM to limit habitat shading — not a structural maximum. Whether a 10 ft stringer span works is a sizing question for engineering review. |
| Pipe-dock water depth past which the engine warns | 6 ft | PartialTier 3 | DockinaBox publishes pipe docks for water "less than 8 feet deep"; at 8 ft or deeper the engine sizes no pipe legs and says so. 6 ft is our conservative call inside that limit, not a cited value: past it the engine flags the depth and suggests floating or piling sections for the deep end, and the legs are still counted. |
| Frame dead load by material | 1.62–4.38 / 3.65–9.8 / 3.09–3.56 psf | SourcedTier 3 | Frame only, read by each section's width and length: among the published frames no wider and no longer than the section, those at the largest size that fits — the widest, then the longest — and the heaviest per square foot of those. A smaller frame weighs more per square foot, so the largest size that fits under the section stands in for a size nobody publishes; where no published frame fits under a section, the smallest published one (the narrowest, then the shortest) stands in, and the dock's explanation says so; the dock uses its heaviest section. Aluminum 1.62–4.38 psf across the published sizes: from Hewitt's 8'X16' Custom Floating Dock Aluminum-No Deck at 207 lb to its 2'X4' Truss Floating Dock Aluminum-No Deck at 35 lb, of 45 published floating aluminum frames from Hewitt, FWM Docks, Multinautic and Patriot Docks. Galvanized steel 3.65–9.8 psf: from Hewitt's 6'X16' Truss Floating Dock Galvanized-No Deck at 350 lb to Merco Marine's 2'X10' Truss Frame - 2" at 196 lb, of 24 frames from Merco, American Muscle Docks and Hewitt (Merco's at the heaviest weight any archived capture of each frame's page carries). Pressure-treated wood 3.09–3.56 psf: Dock Builders Supply's 12', 10' and 8' floating dock plans, weighed at CA DBW 2005 §C2.1.4's 35 lb per cubic foot on the green dressed sizes in NIST PS 20 (a lumber-size product standard, not dock guidance). A PT-framed dock is sized at 13.36 psf, a figure DeckPro derives from Dock Builders Supply's published 10–15 psf lumber-dock dead load: the high end less the 1.64 psf its own figures put on the floats that range counts (28 psf of flotation × 35 lb ÷ 598 lb, the Permafloat it sells), because drum ratings are already net of each float's weight. An aluminum-framed dock is never sized below 5 psf, derived from TechniDock's published 800 lb for an 8' x 20' aluminum section. The drum's own weight is not added. Not yet in the dead load of any dock: pile guides or anchoring hardware, the gangway's reaction on the dock, and water the flotation absorbs (UFC 4-152-07 §6-3.1 names all three). On a dock sized on its frame and decking figures, also connection hardware on a metal frame, and cleats and other attached equipment — a whole-dock figure already counts those by its own page's words. |
| Decking dead load by material | 2.51 – 7.35 psf | SourcedTier 3 | The heaviest published figure for each decking option — panels, and 6 in nominal boards: composite and HDPE boards laid at the 3/8 in dock gap Trex publishes for its boards (borrowed as trade practice for other makers' boards), pressure-treated boards at the board count Dock Builders Supply's plans publish. Aluminum 2.51 psf, derived from two makers: Tommy Docks' ALUMINUM DECKING PANEL REPLACEMENT 47 3/4 X 5 1/2 X 1 (TD-30070), a 5 lb board, laid at the 1/2 in board spacing Patriot Docks publishes for its own panel; the aluminum decks published directly run 1.58–2.27 psf. HDPE panels 4.75 psf: Hewitt's 4' x 4' Classic Weardeck Gray Decking at 76.00 lb (its Sand and Weatherwood list the same), the heaviest published solid HDPE panel — WearDeck's maker says it is "Made of HDPE reinforced with fiberglass". The light-passing grated panels (ThruFlow, Titan Deck, SunWalk), which their listings describe as reinforced polypropylene, glass-reinforced plastic, HDPE or a plastic composite, are lighter than a solid panel: 1.35–2.33 psf across every Hewitt ThruFlow listing and every BARR light-passing panel with a weight, the heaviest Hewitt's 1'x3' Impact Decking Panel-Thruflow Beige at 7.00 lb — documented, not used. American Plastic Lumber's solid HDPE planks, the 14 boards 2 in nominal or thinner with a 5-1/2 in face that are not tongue-and-groove, from the TI-grade 1 x 6 to the BS-grade 2 x 6, run 2.47–6.54 psf at the 3/8 in dock gap — documented, not used. Composite 7.35 psf: Trex Transcend's 2 x 6 at 3.6 lb/ft (the 1x boards run 3.88–4.9 psf). Pressure-treated 4.54 psf: the 2 x 6 deck board Dock Builders Supply's plans call for, at CA DBW 2005 §C2.1.4's 35 lb per cubic foot on its green dressed size, laid at the 8'x16' plan's own count — (34) 2 x 6 x 8' on 128 sq ft, the heaviest decking count in the plans that fits the deck it is drawn on. Cedar 3.2 psf: Multinautic's QPF-495 cedar decking, "two 5 ft. x 5 ft. panels of approximately 80 lbs each" (the kit is sold with or without cedar decking, and the page also lets the buyer use standard lumber); Hewitt's twelve cedar panels run 2.0–2.5 psf (its two Vers-A-Dock panels on the 4' square footprint its Vers-A-Dock page gives). |
| Pile embedment into the bottom | 2 – 10 ft by bottom type | Gap | Trade practice for driven piles runs 4–8 ft; the muck and rock-pin depths sit outside that range and are DeckPro placeholders, and the takeoff labels them so. The real method is geotechnical — pile capacity is a calculation, not a lookup (Timber Pile Design and Construction Manual). Verify with your marine contractor. |
| Spacing between pipe-leg pairs | 8 ft | Gap | Trade practice only — no published source. |
| Frame cross members along the run | every 4 ft | Gap | Trade practice only — no published source. Aluminum and steel frames only: a pressure-treated floating dock is billed on the Dock Builders Supply plan its dead load reads, lengthwise stringers at that plan's spacing and an end board across each end. A pressure-treated pier on piles or pipe legs gets the same layout, labelled on its line as a floating-dock plan borrowed for estimating, with no published source for a fixed pier's framing. |
| Anchor kits for a floating dock | 1 per 200 sq ft, minimum 2 | Gap | Trade practice only. Anchoring is site-specific — depth, exposure and bottom all govern; have it reviewed. |
How flotation is actually sized
Catalog buoyancy is a full-submersion figure — a drum rated 500 lb delivers 500 lb only when the dock is awash — so the rating is credited at design submergence, and the dock’s dead load alone is what rides there.
01 · Dead load
One 8′×20′ section, aluminum frame and aluminum panel decking: 1.62 psf frame (8 × 16 ft) + 2.51 psf decking = 4.13 psf, under the 5 psf whole-dock figure DeckPro derives from the TechniDock float drum guide's published 800–1,200 lb for a typical 8' × 20' aluminum section (800 lb ÷ (8 ft × 20 ft)), which governs: 5 psf. That is 800 lb over 160 sq ft — the whole-dock figure DeckPro derives from a published one (Tier 3 — documented practice: TechniDock float drum guide), which asks more than the largest published frame that fits under the section, 8 × 16 ft (Hewitt custom floating dock frame listing), and the heaviest published decking figure (Tommy Docks aluminum panel page + Patriot Docks aluminum decking panel page).
02 · Required flotation
The worst of three: dead at 45% submergence (5 ÷ 0.45 = 11.1 psf), the reserve-buoyancy rule — dead plus FULL live load with 2″ of the 16″ drum still above water, so (5 + 20) ÷ 0.875 = 28.6 psf — and the published 28 psf residential floor. Here the reserve buoyancy at full live load governs, at 28.6 psf. A pressure-treated frame and deck (13.36 psf dead) asks 38.1 psf.
03 · Drum count
160 sq ft × 28.6 psf = 4,571 lb ÷ 500 lb per drum = 9.1, rounded to 10 so the drums come whole and pair across the width — 5,000 lb of catalog buoyancy, or 31.3 psf.
04 · Where it floats
800 lb of dead load against 5,000 lb of buoyancy = 16% submerged at rest, and at dead plus full live load 3.2″ of the 16″ drum stays above water — past the 2″ the reserve rule asks.
Live load is carried by an explicit rule, not by an assumption. UFC 4-152-07 §6-3.3.2 states it geometrically — at least 2″ of the pontoon stays above water at dead load plus full live load — which is a stronger criterion than the manufacturer submergence practice and, at the published dead loads, is what governs every residential dock. The two agree where they overlap: the published 28–35 psf totals were written for wood docks at 10–15 psf dead, and putting those through the same reserve rule gives (10…15 + 20) ÷ 0.875 = 34–40 psf — the top of the published band and a little past it. Comparing loads against full-submersion catalog ratings instead, as this engine once did, lands at ~21–23.5 psf: below everything published, and invisible unless someone states the basis. UFC 4-152-07 §6-3.3.2 · Ameren App. B §7.7.1 · Dock Builders Supply
The checks the engine runs
17 site conditions the engine flags, each with its reason and what to do. The text below is generated by running the engine, not written for this page — so a check that stopped firing would disappear from here rather than become a claim nothing backs.
A floating dock where the water drops to 1.5 ft at seasonal low.
Only 1.5 ft at low water — documented manufacturer practice (Tier 3, EZ Dock: 2–3 ft minimum) wants ~2.5 ft so floats stay off the bottom, and some states restrict float grounding (Tier 1, WA WAC 220-660-140(3)(c)(ii): approved in reservoirs and impoundments only when the water level is dropped).
What to do: Consider a pipe dock in the shallow span, or extend the run to deeper water.
A pipe / roll-in dock reaching out into 7 ft of water at seasonal high.
7 ft at high water is inside documented manufacturer practice for pipe docks (Tier 3, DockinaBox: water "less than 8 feet deep" on a fairly solid bottom) but past our conservative 6 ft default — a judgment call, not a citation. The legs below are counted by the same trade-practice rule as a shallower dock; bracing at this depth is not sized here.
What to do: Have your marine contractor confirm the legs and their bracing at this depth, or switch the deep-water end to floating or piling sections.
A 4 ft gangway spanning 2 ft of seasonal water-level travel.
4 ft gangway over 2 ft of water-level travel is steeper than the 3:1 slope CA DBW 2005 §F2.9 holds at or above 0.0 MLLW (coastal, §F2.9.1) and for at least 90% of the time inland (§F2.9.2) — the Tier 2 threshold this engine checks. §F2.9 does publish a 2½:1 relaxation, but only BELOW 0.0 MLLW or for no more than 10% of the time, and neither can be evaluated from a hand-entered seasonal high and low.
What to do: Use at least 7 ft of gangway (about 3.2× the level variation: a 3:1 slope with the shore end at high-water deck level), or have a marine contractor size it against measured water-level data for your site.
A gangway 2½ ft (30 in) wide.
A 2.5 ft (30 in) gangway is narrower than CA DBW 2005 §F2.4's "Recommended minimum clear gangway width is 36 inches" (Tier 2) — and clear width is measured between the handrails, so the walkway is narrower still.
What to do: Specify a gangway with at least 36 in clear between its handrails.
A 3 ft × 10 ft floating walkway on a pressure-treated frame with composite decking.
Not every drum the flotation needs fits under its section: section 1 (3 ft × 10 ft) needs 3 and has room for 2, laid lengthwise or crosswise in the 24 in × 48 in footprint the drum publishes (Tier 3). The takeoff bills what the flotation requires, never fewer — but that count cannot be mounted under the section as drawn.
What to do: Widen or lengthen the section, or choose a float with more buoyancy for its footprint, and have your dock supplier confirm the float layout before ordering.
A floating dock on an open, unsheltered shoreline.
Open exposure — wind and wave loads will work the anchoring hard. Marina design guidance (Tier 2, CA DBW 2005 §C2.4.1) designs for ≥15 psf wind; sheltered-water rules of thumb no longer apply.
What to do: Add anchor kits, consider wave attenuation or a more sheltered layout — and have a marine engineer review the anchoring.
A floating dock anchored over a soft muck bottom.
Muck bottom holds deadweight anchors poorly (trade practice, no published standard — verify anchoring with your marine contractor).
What to do: Upsize deadweights or switch to helical/auger anchors.
A piling dock over a rock bottom.
Rock bottom — piles must be pinned/socketed rather than driven (trade practice, no published standard — verify the anchorage detail with your marine contractor).
What to do: Budget for rock anchoring hardware and drilling time.
A piling dock on a lake the owner expects to pull out each fall.
Piling docks stay in year-round — ice sheets can jack unprotected piles (trade practice, no published standard — verify ice conditions with your marine contractor).
What to do: Confirm ice conditions; consider pipe or floating sections where ice-out is required.
An 8 ft-wide pier on a Wisconsin lake.
Wisconsin DNR exempts a pier no more than 6 ft wide, with one loading platform wider than that if the platform’s surface area does not exceed 200 sq ft (Tier 1, Wis. Stat. 30.12(1g)(f)); on this dock sections 1–2 are 8 ft wide and cover 320 sq ft, over the 200 sq ft a loading platform may cover. Over that line the dock is not exempt — it becomes a permit conversation with Wisconsin DNR, not a violation.
What to do: Bring the wide parts to 6 ft, or into a single loading platform of 200 sq ft or less, or take the design to your county’s Wisconsin DNR water management specialist. We do not tell you that you are permitted — that word belongs to the agency.
A 5 ft-wide gangway to a floating dock on a Washington lake.
Washington Department of Fish and Wildlife limits residential ramps to 4 ft wide and requires grating over the entire ramp surface (Tier 1, WAC 220-660-140(3)(c)(iv)(D)); the gangway is 5 ft wide. That is a ceiling in the rule as written, not a review threshold — take the design to Washington Department of Fish and Wildlife before you quote it; whether an exception reaches this site is theirs to say.
What to do: Either bring the gangway to 4 ft or take the wider design to the WDFW habitat biologist for your county (Hydraulic Project Approval). We do not tell you that you are permitted — that word belongs to the agency.
A TVA-reservoir dock whose sections need a 1,200 sq ft siting rectangle; TVA does not count the access walkway.
Tennessee Valley Authority sites docks within a 1,000 sq ft rectangle at the lakeward end of the access walkway, not counting the walkway (Tier 1, 18 CFR 1304.204(a)–(b)). This dock needs a 20 × 60 ft rectangle, 1,200 sq ft, reading the gangway as the access walkway, which the rule does not count — between Tennessee Valley Authority’s two maximums: 1,800 sq ft in an area of preexisting development, 1,000 sq ft elsewhere. Which applies depends on whether the lot is in an area of preexisting development — a subdivision recorded before November 1, 1999 in which TVA permitted a facility before that date or, with no subdivision, within a quarter mile of a facility TVA permitted before then, which we do not hold.
What to do: Ask TVA’s Section 26a permitting office for this reservoir whether this lot is in an area of preexisting development. If it is not, this dock is over the 1,000 sq ft maximum as drawn.
A TVA-reservoir dock reaching 180 ft out to find water.
Tennessee Valley Authority holds docks and walkways to 150 ft from the shoreline, or ⅓ of the waterway (the distance to the opposite shoreline), whichever is less (Tier 1, 18 CFR 1304.204(c)); this one reaches 180 ft from the shore end of the drawing. That is a ceiling in the rule as written, not a review threshold — take the design to Tennessee Valley Authority before you quote it; whether an exception reaches this site is theirs to say.
What to do: Shorten the run, or take the reach to TVA’s Section 26a permitting office for this reservoir. The one-third-of-the-waterway test also needs the distance to the opposite shoreline, which we do not hold.
A fixed piling dock 12 in above high water on a TVA reservoir.
Tennessee Valley Authority sets fixed piers and docks at least 18 in above full summer pool on Pickwick, Wilson, Wheeler, Guntersville and Nickajack Reservoirs, and at least 24 in on all other reservoirs (Tier 1, 18 CFR 1304.204(d)); this fixed deck is 12 in above the high water entered, under the 18 in minimum on every TVA reservoir if that high water is full summer pool. We read the deck as 12 in above the high water entered; TVA measures from full summer pool, so confirm which level that is.
What to do: Raise the deck, or confirm full summer pool for this reservoir with TVA’s Section 26a permitting office for this reservoir.
A floating dock on a Washington lake.
Washington Department of Fish and Wildlife’s rule requires piers to extend far enough from the shoreline that floats do not impact juvenile salmonid migration, feeding and rearing areas, and approves grounding of floats in reservoirs and impoundments only at times of the year when the water level is dropped (Tier 1, WAC 220-660-140(3)(c)(ii)). A float that grounds here is a permit question, not the nuisance it is elsewhere. Your entered low-water depth is 3 ft.
What to do: Confirm the depth at your lowest recorded water, not seasonal low, and raise it with the WDFW habitat biologist for your county (Hydraulic Project Approval) if the floats could touch — or if this lake is a dam-regulated impoundment, ask how the drawdown allowance applies.
A dock on a U.S. Army Corps reservoir in Minnesota.
We applied Minnesota DNR’s rule (Tier 1, Minn. R. 6115.0210 subp. 4(A)) to this dock. On a U.S. Army Corps reservoir, the lake’s own Shoreline Management Plan also sets dock limits, lake by lake, and we do not hold per-lake plans — ask the Corps lake office that operates this reservoir as well.
What to do: Confirm which rule governs this water with your Minnesota DNR area hydrologist before you quote.
A dock with no state or water body recorded yet.
No state or water body recorded, so no dimensional cap has been checked on this dock. There is no national dock code, so the Tier 1 caps that govern width, footprint and reach come from your waterway authority — and we only publish caps we have verified against the agency’s own document.
What to do: Tell us the state and the water and we will check the dimensional caps we have on file (5 states plus TVA reservoirs today). Name your U.S. Army Corps district (Section 10 / 404), your state waterway agency, and your local shoreline zoning office before you quote — and if this is a TVA or Corps reservoir, say so, because the reservoir operator’s rules govern there.
The DOCK-BP prefix is deliberate: these are best-practice checks, not code checks, because there is no code to check against. Past documented practice the engine flags the condition instead of passing it silently, and the flag rides with the design. It refuses outright in two places. Round or pipe pontoon flotation, which its rectangular-drum math does not describe: there it produces no float count at all. And a pipe dock in water 8 ft deep or deeper, where DockinaBox’s published practice (“less than 8 feet deep”) ends: there it sizes no pipe legs.
The documents themselves
Every document behind our sizing numbers, with the file facts that let you verify our transcription against your own download. The permitting documents behind the jurisdiction caps link from the caps table above.
Lake of the Ozarks Permit Requirements, Appendix B (rev. 2025-06-30)
Ameren Missouri (FERC Osage Project No. 459) · Tier 1 — legal force
§7.7.1 "Deck live loading for flotation calculations on uncovered docks shall be 20 pounds per square foot (psf)", with a 400 lb load on any 1 sq ft that "need not occur simultaneously" — the residential live load. §7.9 "Minimum live loads shall be 30 psf on deck" for access structures — the residential gangway rating. A permit mandate on Lake of the Ozarks, where it has legal force; everywhere else it is the only published set of residential dock criteria we have found, which is why the residential basis reads it.
3,158,328 bytes, MD5 9b13b946775ab5233cef475c44fdc907.
ameren.com — Lake of the Ozarks Appendix BLayout and Design Guidelines for Marina Berthing Facilities (2005)
California Department of Boating and Waterways · Tier 2 — published guideline
§C2.2 uniform live load 25 psf minimum · §C2.3 400 lb point load · §C3 freeboard (dead-load-only 14–24", loaded minimum 10") · §C2.4.1 wind ≥15 psf · §C2.1.4 treated lumber in a floating dock weighs not less than 35 lb per cubic foot (the unit weight of every pressure-treated frame and deck figure) · §F2.9 gangway 3:1 maximum slope · §F2.2 gangway 100 psf · §F2.4 36" minimum clear width
140 pp., 3,475,710 bytes, MD5 afda6fd587ae5de16de612630ef5a6c6. The official link now serves a one-page accessibility notice; the full document is available from parks.ca.gov/DocumentRequest, and the verified mirror we checksummed is chet-aero.com/wp-content/uploads/2016/11/guide05.pdf.
dbw.parks.ca.gov — Guide05.pdfFlotation Calculation for Dock Floats
Dock Builders Supply · Tier 3 — documented practice
The published residential method in full: total flotation 28–35 psf by framing/decking combo, dead load 10–15 psf, design at roughly 40% submergence and never past 50%, floats at all corners and no more than 8 ft apart. Its 10–15 psf lumber-dock dead load counts "connections, flotation units, and all permanently-attached equipment"; DeckPro derives 13.36 psf from it for every pressure-treated frame — the high end less the floats' own weight, its lightest multiplier, 28 psf, × the 35 lb ÷ 598 lb of the lightest 24" x 48" x 16" drum per pound of rating it sells. The page publishes the range, not 13.36.
dockbuilders.com — flotation calculationHow to Calculate Dock Flotation
American Muscle Docks · Tier 3 — documented practice
"A marina expecting more than a few people needs about 40 lbs. per square foot" — the marina total-flotation floor. Beside it, "about 30 lbs. per square foot" for a dock with a wood frame and wood decking, inside Dock Builders Supply's residential band. Fetched live 2026-09-28.
americanmuscledocks.com — calculate dock flotationDock Float Specifications
Formex · Tier 3 — documented practice
Per-size buoyancy table, and the caveat that governs all of them: the published buoyancy figure is for total submersion in fresh water. Formex declines to specify how much flotation a dock needs — which is exactly why the sizing basis has to be stated, not assumed.
formex.com — float specificationsEagle Floats Buoyancy Chart
Hendren Plastics (Eagle Floats) · Tier 3 — documented practice
The one maker chart found that lists a drum's load part-way down: for the 2 x 4 x 16, 440 lb at 2 in out of water and 220 lb at 8 in out, and "Max values indicate the amount of weight required to submerge the entire float" (530 lb). The chart does not say whether its values were tested or calculated. The engine's 2 in reserve check is read against it.
87,450 bytes, MD5 89c2214b8acb767da713be81f288a87b (retrieved 2026-09-27).
hendrenplastics.com — Eagle Floats buoyancy chartMolded Foam Filled Plastic Dock Floats
BARR Plastics (PermaFloat) · Tier 3 — documented practice
PermaFloat BD2448-16 at 598 lb, under the column heading "Rating is for float being fully submerged". A dealer page; it does not name the molder.
barrplastics.com — PermaFloat dock floatsHow Deep Does the Water Need to Be for a Floating Dock?
EZ Dock · Tier 3 — documented practice
Floating docks need 2–3 ft of water minimum, 3–5 ft typical.
ez-dock.com — water depthWhat Is a Pipe Dock?
DockinaBox · Tier 3 — documented practice
Pipe docks belong in water under 8 ft, on a firm bottom.
dockinabox.com — pipe docksReissuance and Modification of Nationwide Permits (2026)
U.S. Army Corps of Engineers · Federal Register · Tier 1 — legal force
NWP 2 covers structures in artificial canals within residential developments — the only nationwide permit squarely covering a residential dock. New docks in natural navigable waters typically ride a district Regional General Permit or an individual Section 10 permit.
91 FR 768–886, published 2026-01-08. Effective 2026-03-15, expires 2031-03-15.
federalregister.gov — 2026 NWPsPier Planner 2026
Wisconsin DNR · Tier 1 — legal force
Exempt pier maximum 6 ft wide; loading platform at most 200 sq ft; pre-2012 grandfathering.
1,671,890 bytes, MD5 084f6a86e57b5384c1ae7bc5b527594e.
dnr.wisconsin.gov — Pier Planner 2026WAC 220-660-140 — Residential and public recreational docks, piers, ramps, floats, watercraft lifts, and buoys in freshwater areas
Washington (WDFW administrative rule) · Tier 1 — legal force
Residential piers and docks 6 ft wide for the first 30 ft from shore, measured from mean low water (50 ft on the Columbia River); residential ramps 4 ft, fully grated; at least 30% or 50% grating; pier underside at least 1.5 ft above the ordinary high water line; float grounding approved in reservoirs and impoundments only when the water level is dropped.
app.leg.wa.gov — WAC 220-660-140Construction Guidelines in Florida for Minor Piling-Supported Structures Constructed in or over Submerged Aquatic Vegetation (SAV), Marsh or Mangrove Habitat (Aug 2001, rev. 2008)
U.S. Army Corps of Engineers / National Marine Fisheries Service (Jacksonville District) · Tier 1 — legal force
"The spacing of pilings through SAV beds shall be a minimum of 10 feet on center" — an environmental minimum to limit shading, which is why our 10 ft pile-bent spacing is marked Partial rather than a structural span. Also the reference-only Florida row above: a 4 ft maximum width over SAV, decking at least 5 ft above mean high water, and terminal platforms of 160 sq ft grated or 120 sq ft planked.
Internet Archive capture, 22,715 bytes, MD5 33c8ec00e3820c45c551937918366875; the usace.army.mil original refuses automated fetches.
web.archive.org — USACE/NMFS dock guidelinesTimber Pile Design and Construction Manual
American Wood Preservers Institute · Tier 2 — published guideline
The authority for what our embedment numbers are NOT: pile capacity is a geotechnical calculation, not a table lookup. We cite it to mark the boundary, not to justify a value.
145 pp., MD5 321871c564ee4cd8d2103c5c8b9a2309.
piledrivers.org — Timber Pile ManualCustom Floating Dock Frame
Hewitt · Tier 3 — documented practice
Frame-only weights (float brackets, no decking), among them 8'X16' Custom Floating Dock Aluminum-No Deck at 207 lb (1.62 psf, the aluminum figure for a section 8 ft by 16 ft or larger), 4'X12' Custom Floating Aluminum-No Deck (For Thruflow) at 114 lb, and 8'X20' Custom Floating Galvanized-No Deck (For Thruflow) at 875 lb (5.47 psf, the galvanized figure for a section 8 ft by 20 ft or larger).
Every aluminum, galvanized and For Thruflow size the page's selector offers, each at its own address under this one (e.g. /aluminum-8-16, /aluminum-thruflow-4-12, /galvanized-thruflow-8-20); 17 carry a weight.
hewittrad.com — custom floating dock framesTruss Floating Dock Frame
Hewitt · Tier 3 — documented practice
Frame-only weights, among them 2'X4' Truss Floating Dock Aluminum-No Deck at 35 lb (4.38 psf, the heaviest aluminum frame per square foot anyone publishes), 4'X8' at 88 lb and 6'X16' Truss Floating Dock Galvanized-No Deck at 350 lb.
Every aluminum, galvanized and For Thruflow size the page's selector offers, each at its own address under this one (e.g. /none-aluminum-2-4, /none-galvanized-steel-6-16); 21 carry a weight. Also the standalone listing www.hewittrad.com/p/docks/truss-floating/8x16-galvanized-truss-floating-dock-for-thruflow-no-deck (500 lb). Left out as a data-entry error: 8'x4' Truss Floating Aluminum-No Deck (For Thruflow) at 896.00 lb, 28 psf, where the same line's 4'X8' lists 86 lb.
hewittrad.com — truss floating dock framesAluminum Floating Docks (frame table)
FWM Docks · Tier 3 — documented practice
"4’ x 10’ Frame Frame Weight: 88 lbs", "5’ x 10’ Frame Frame Weight: 108 lbs", 5’ x 12’ at 115 lb and 6’ x 10’ at 118 lb — the aluminum figures for sections of those sizes. The same five rows in every capture of the page that carries them.
Internet Archive capture of 2026-03-13; the live site refuses automated fetches.
web.archive.org — FWM Docks aluminum floating docksTruss Frame - 2" listings (TF-210-2 through TF-810-2)
Merco Marine · Tier 3 — documented practice
Galvanized truss frames of 2 x 2 x 3/16 angle in 10 ft modules, each at the heaviest weight any Internet Archive capture of its page carries, under every URL scheme Merco's site has used (/shop/product/ 2021–2026, Dock-Hardware/Truss-Frames/ 2016–2018, our-products/truss-frames/ 2011), cited from the capture that carries it: 196 lb at 2 ft (9.8 psf), 201 lb at 3 ft (6.7), 233 lb at 4 ft (5.83), 319 lb at 5 ft (6.38), 332 lb at 6 ft (5.53) and 410 lb at 8 ft (5.13). The last two are the 2011 captures' "weights 332 lbs" and "weights 410 lbs"; every later capture lists 300 and 383.
Internet Archive captures; the live shop refuses automated fetches. Also web.archive.org/web/20250917050105/https://www.mercoboatdocks.com/shop/product/3x10-truss-frame---2/4055, web.archive.org/web/20260217122711/https://www.mercoboatdocks.com/shop/product/4x10-truss-frame---2/4061, web.archive.org/web/20260306075927/https://www.mercoboatdocks.com/shop/product/5x10-truss-frame---2/4067, web.archive.org/web/20110101173416/http://www.mercoboatdocks.com/our-products/truss-frames/2-angle/6x10-truss-frame-2-inch and web.archive.org/web/20110101173506/http://www.mercoboatdocks.com/our-products/truss-frames/2-angle/8x10-truss-frame-2-inch.
web.archive.org — Merco Marine truss framesFloating dock drawings (8'x16', 10'x20', 12'x12')
Dock Builders Supply · Tier 3 — documented practice
The lumber each plan lists: two 2x8x8 end boards and nine 2x8x16 stringers on the 8'x16' (3.56 psf); two 2x8x10 headers and nine 2x8x20 — or 2x10x20 — stringers on the 10'x20' (3.53 psf with the 2x10s); two 2x8x12 end boards and eleven 2x8x12 stringers on the 12'x12' (3.09 psf), each weighed at 35 lb per cubic foot (CA DBW 2005 §C2.1.4) on its green dressed size. The plans deck in 5/4 x 6 or 2 x 6 boards; the pressure-treated decking figure is laid at the 8'x16' plan's count, (34) 2 x 6 x 8' on 128 sq ft — the 10'x20' plans' (43) and the 12'x12' plans' (26) overfill the decks they are drawn on at the boards' green 5-5/8 in face, so they are not taken.
Six plans; this one MD5 bde6099e829732bb1869db1320044171. Also cdn.shopify.com/s/files/1/0635/8597/6404/files/floating_dock_drawing-10x20-8FD-3416-12and16oc-4.pdf (MD5 0ed911eacd942836e8d4ddd06ca5b33b) and cdn.shopify.com/s/files/1/0635/8597/6404/files/floating_dock_drawing-12x12-4FD-4512-4x8ramp-12-15oc-6.pdf (MD5 7c17f0171d4105e5db14026a46a47964).
dockbuilders.com — floating dock plansPS 20-20 American Softwood Lumber Standard, Table 3
NIST / U.S. Department of Commerce · Published reference — not dock authority
A lumber-size product standard, not dock guidance. Its green dressed sizes — 2 in nominal to 1-9/16 in, 6 to 5-5/8, 8 to 7-1/2, 10 to 9-1/2 — are the sections every pressure-treated frame and deck board is weighed on, because a dock member is wet.
MD5 fcd57544870e1c84a799ea1285d85f84.
nist.gov — PS 20-2024" x 48" x 16" dock float listings
Dock Builders Supply · Tier 3 — documented practice
Buoyancy and weight for each drum it sells in the size the engine counts: Permafloat 598 lb and 35 lb, DPI 588 and 35, Eagle 540 and 35, CW 600 and 37. The lightest per pound of rating, the Permafloat, sets the float share taken off its lumber-dock dead load. These are dealer listings that give "Buoyancy" with no submersion condition, and three of them add "* All dimensions, weights, and buoyancies are approximate" (re-checked 2026-09-28), so they are not among the full-submersion ratings the float-drum row ranges over; Eagle's own chart gives its 2 x 4 x 16 as 530 lb fully submerged.
Also dockbuilders.com/products/dpi-dock-float-24-x-48-x-16, dockbuilders.com/products/eagle-dock-float-24-x-48-x-16 and dockbuilders.com/products/cw-dock-float-24-x-48-x-16.
dockbuilders.com — 24" x 48" x 16" floatsALUMINUM DECKING PANEL REPLACEMENT 47 3/4 X 5 1/2 X 1 (TD-30070)
Tommy Docks · Tier 3 — documented practice
A 1 x 5-1/2 x 47-3/4 in aluminum board: "Each panel weighs a mere 5lbs". Laid at Patriot Docks' published 1/2 in board spacing it comes to 2.51 psf — a figure derived from two makers, heavier than every aluminum deck published directly (1.58–2.27 psf).
tommydocks.com — aluminum deck boardAluminum Decking Panel
Patriot Docks · Tier 3 — documented practice
A 25 lb panel of 5-1/2 in aluminum boards at "Board Spacing: 1/2"" — the spacing the Tommy Docks board is laid at.
patriotdocks.com — aluminum decking panel4' x 4' Classic Weardeck Gray Decking
Hewitt · Tier 3 — documented practice
"SKU: D1DCW4X4G Weight: 76.00 lbs" for a 4' x 4' panel — 4.75 psf, the heaviest published solid HDPE panel and the figure the HDPE panels option is sized on. Hewitt's page does not say what WearDeck is made of; its maker does (the next entry).
Also www.hewittrad.com/p/docks/decking/4-x-4-classic-weardeck-sand-decking (D1DCW4X4S) and www.hewittrad.com/p/docks/decking/4-x-4-classic-weardeck-weatherwood-decking (D1DCW4X4W), 76.00 lb each.
hewittrad.com — WearDeck decking panelWearDeck home page
WearDeck (J.R. Plastics Corporation) · Tier 3 — documented practice
"Made of HDPE reinforced with fiberglass" — the maker's own statement of what WearDeck is, the reason Hewitt's Classic Weardeck panel counts as a solid HDPE panel.
Internet Archive capture of 2023-08-11.
web.archive.org — weardeck.com1'x3' Impact Decking Panel-Thruflow
Hewitt · Tier 3 — documented practice
"Weight: 7.00 lbs" for a 1'x3' light-passing panel — 2.33 psf, the heaviest light-passing grated panel published. Hewitt's own page calls ThruFlow "reinforced polypropylene"; the light-passing grated panels (ThruFlow, Titan Deck, SunWalk), which their listings describe as reinforced polypropylene, glass-reinforced plastic, HDPE or a plastic composite, are lighter than the solid HDPE panel — documented, not used.
hewittrad.com — ThruFlow decking panelDecking panel listings (ThruFlow, SunWalk, Titan Deck)
BARR Plastics (dealer) · Tier 3 — documented practice
Weights for every light-passing panel BARR lists with one — ThruFlow, grey and maple ("Made of fibreglass reinforced polypropylene" on its 1'x3', 1'x4' and 1'x5' pages, whose spec lines also give polypropylene or a composite), and ThruFlow XP ("High-quality polypropylene" on its 1'x3' and 1'x5' pages, "Material: High-density polyethylene (HDPE)" on its 1'x4') at 1'x3', 1'x4', 1'x5' and 4'x4', SunWalk ("GLASS REINFORCED") at 3'x4', 4'x4' and 5'x4', and Titan Deck ("100% Polypropylene"): 1.35–1.83 psf, all under Hewitt's 2.33 — documented, not used. Where a page states more than one weight for a panel, the heaviest is taken.
barrplastics.com — decking panelsPremium Plastic Lumber Sizes & Profiles
American Plastic Lumber · Tier 3 — documented practice
Solid HDPE lumber ("Solid HDPE with UV inhibitors", the page's own product data) in four grades (BX, BS, TI, RW): its 14 boards 2 in nominal or thinner with a 5-1/2 in face that are not tongue-and-groove (APL names some of them 6 in nominal and some 5-1/2 in), from the TI-grade 1 x 6 at 1.21 lb per foot to the BS-grade 2 x 6 at 3.2, run 2.47–6.54 psf at the 3/8 in dock gap. Its 1/2 x 6 boards, its tongue-and-groove boards, its BS-grade 3 x 6 (2.5 x 5.5 in, 4.8 lb per foot) and its 4 x 6 and 6 x 6 timbers are left out. What a solid HDPE plank weighs, documented beside the HDPE panels figure; the option is sized on a panel, so a plank does not set it.
american-plasticlumber.com — lumber sizesTrex Transcend Decking & Fascia cut sheet
Trex · Tier 3 — documented practice
The 2" x 6" board, 1.3 x 5.5 in, at "Weight per Lineal Foot" 3.6 lbs — 7.35 psf at the 3/8 in dock gap, the heaviest composite board published (the 1" x 6" is 2.4 lbs).
MD5 c583b05a13cb7f158b507b0ad3b78dfb.
images.trex.com — Transcend cut sheetFiberon Decking
Burroughs Hardwoods (dealer) · Tier 3 — documented practice
Fiberon's Symmetry and Horizon boards, .935 x 5.4 in at "Board Weight: 2.36 lbs./lineal ft." (4.9 psf at the 3/8 in dock gap), and its ProTect Advantage and Good Life boards. Fiberon's own pages publish no board weight.
burroughshardwoods.com — Fiberon specsDecking Installation Guide, Chapter 4
Trex · Tier 3 — documented practice
"For docks, a 3/8" (10mm) width-to-width gap between boards is recommended" — Trex's dock gap for its own boards, and the gap every composite and HDPE board figure is laid at (trade practice for the boards that are not Trex's). Pressure-treated boards are laid at the Dock Builders Supply plan's own board count instead.
MD5 13f9fbf49c445b15dc2453d4a0c7f831.
documents.trex.com — installation guideQPF-495 floating or stationary aluminum dock
Multinautic · Tier 3 — documented practice
"Ready with or without cedar decking included" and "the wood decking on each section can be assembled as two 5 ft. x 5 ft. panels of approximately 80 lbs each" — 3.2 psf, the heaviest published cedar decking figure and the one the cedar option is sized on. The same page also lets the buyer use standard lumber, so the figure is read as the kit's cedar decking. Its "5 ft. x 10 ft. aluminum frame weighs approximately 95 lbs" is one of the aluminum frames weighed.
multinautic.com — QPF-495 dock4'X8' Sectional Decking Panel-Cedar
Hewitt · Tier 3 — documented practice
"Weight: 80.00 lbs" for a 4'x8' western red cedar panel — 2.5 psf, the heaviest of Hewitt's twelve cedar panels (2.0–2.5 psf, among them a 4'x8' Roll-A-Dock panel sold as a second at 71 lb), under Multinautic's 3.2. Its two Vers-A-Dock panels (35 and 37 lb) list no size; its Vers-A-Dock page gives "The 4' square deck panels", which puts them at 2.19 and 2.31 psf.
The Vers-A-Dock footprint: www.hewittrad.com/products/docks/vers-a-dock (fetched 2026-09-28), which also puts the Vers-A-Dock aluminum and ThruFlow panels at 2.25 and 1.56–1.69 psf.
hewittrad.com — cedar decking panelFloat Drums: The Complete Guide to Dock Flotation
TechniDock · Tier 3 — documented practice
A typical 8' x 20' aluminum section "might weigh 800 to 1,200 pounds depending on the decking material", counting "aluminum extrusions, decking, hardware, cleats, electrical conduit, and any fixed equipment". DeckPro derives 5 psf from the low end (800 lb ÷ 160 sq ft), the only figure the page applies to every decking, and holds it as the floor under every aluminum-framed dock: where the frame and decking figures sum to less — aluminum decking on most frames 4 ft x 10 ft and larger, cedar decking on sections 8 ft x 16 ft and larger — it lifts them to 5. A manufacturer blog, hedged ("might weigh").
technidock.com — float drum guideUFC 4-152-07, Design: Small Craft Berthing Facilities
U.S. Department of Defense (USACE / NAVFAC / AFCESA) · Tier 2 — published guideline
§6-3.3.2, 2 in of pontoon above water at dead plus full live load — the reserve-buoyancy rule. §6-3.1, what a floating dock's dead load should also include: "the weight of pile guides or anchoring hardware, the superimposed dead load of the gangway reaction on the dock, and an allowance for weight gain due to water absorption in the dock flotation" — none of the three is in our dead load yet.
2,657,538 bytes, MD5 0b656dc29af5594333d834ba3317b7d5.
wbdg.org — UFC 4-152-07ASCE MOP 50, Planning and Design Guidelines for Small Craft Harbors, is the marine engineer’s standard of practice and is paywalled. We name it as what an engineer designs to, and we never quote a number from it that we have not verified in a document we can hand you.
Where this stops
Three limits worth knowing before you lean on a dock takeoff, stated plainly because finding them out later is expensive.
- Jurisdiction coverage is 6 authorities deep, not fifty. The measurement captures your state and water body and checks the caps above where we hold them — Wisconsin, Minnesota, Washington fresh water, Florida, New York tidal waters, and TVA reservoirs. Everywhere else the estimator states plainly that it has no rules on file and names who to ask; it will not invent a cap, and a checked cap is still not a permit.
- Deck freeboard is not checked against the published band — CA DBW 2005 §C3 (Tier 2): 14–24″ at dead load only, 10″ minimum loaded. What the engine does hold is 2″ of drum above water at dead plus full live load when it sizes flotation (UFC 4-152-07 §6-3.3.2, Tier 2), and it flags a missing boarding ladder where the deck stands more than 3 ft above design low water (§6-4.1).
- This is estimating, not engineering. Nothing here is stamped. The estimator sizes flotation on the residential load basis and the free flotation calculator also runs the marina basis, each naming its document, but a flotation count is not a marina design: open water raises a flag telling you to have a marine engineer review the anchoring, and a crowd, a vehicle or a boat lift is not an input at all — those belong with a marine engineer too.
Common questions
- Is there a building code for docks?
- There is no national dock code. Unlike a deck, which has the International Residential Code and the AWC DCA 6 prescriptive span tables, a residential dock has no national standard and no prescriptive table. Authority is split three ways: rules with legal force (your U.S. Army Corps district under Section 10 / 404, your state waterway agency, and local shoreline zoning), published design guidelines (California Department of Boating and Waterways, Layout and Design Guidelines for Marina Berthing Facilities, 2005 — citable by section but not law), and documented manufacturer practice (published flotation methods, minimum water depths, pipe-dock limits). Any dock product claiming code compliance is describing a code that does not exist.
- How much flotation does a floating dock need?
- Catalog buoyancy ratings are full-submersion figures — a 500 lb drum delivers 500 lb only with the dock awash — so no rating is compared with a load directly. Float drums are counted to the worst of three criteria. The dock’s dead load alone rides no deeper than 45% of the drum’s height, the middle of the Dock Builders Supply published flotation method: design near 40% submergence, never past 50% (Tier 3 — documented practice). At dead load plus the FULL live load, at least 2 in of the 16 in drum stays above water — the reserve-buoyancy rule (Tier 2 — published guideline: UFC 4-152-07, Design: Small Craft Berthing Facilities §6-3.3.2). And total flotation never drops below the published floor for the load basis: 28 psf residential (Tier 3 — documented practice: Dock Builders Supply) or 40 psf marina (Tier 3 — documented practice: American Muscle Docks). The live load comes from the basis — 20 psf residential (Tier 2 — published guideline: Ameren Lake of the Ozarks Permit Requirements, Appendix B §7.7.1, permit-mandated on that lake only) or 25 psf marina (Tier 2 — published guideline: CA DBW, Layout and Design Guidelines for Marina Berthing Facilities, 2005, §C2.2). One 8′ × 20′ aluminum-frame section on the residential basis needs 4,571 lb of catalog buoyancy — 10 drums rated 500 lb, set by the reserve buoyancy at full live load. Build the same section in pressure-treated wood and its 13.36 psf dead load raises what the reserve-buoyancy rule asks, from 28.6 to 38.1 psf: 14 drums. The free dock flotation calculator runs the same sizing on your dock and names the criterion that governed.
- How deep does the water need to be for a floating dock?
- EZ Dock publishes 2–3 ft as the minimum, with 3–5 ft typical; we size to 2.5 ft of depth at seasonal low water and flag anything shallower. Depth is not only a performance question: Washington approves float grounding only in reservoirs and impoundments when the water level is dropped, and otherwise expects piers to keep floats off juvenile salmonid rearing areas (WAC 220-660-140(3)(c)(ii)), so in some states a dock that touches bottom at low water is a regulatory problem rather than a nuisance.
- How steep can a dock gangway be?
- California DBW publishes TWO slope limits, and both reference the water rather than the dock: 3:1 at or above 0.0 MLLW and 2½:1 below it (§F2.9.1), or inland, 3:1 for at least 90% of the time and 2½:1 for no more than 10% (§F2.9.2). Neither a tidal datum nor an exceedance duration can be derived from a seasonal high and low typed into a form, so the estimator checks the STRICT 3:1 arm only and states that limitation on every gangway. It reads 3:1 as 3 ft across for every foot of rise, with the shore end at the float's high-water deck level, so a 2 ft swing needs at least 7 ft of gangway. The same document recommends a 36" minimum clear width (§F2.4), and sets guards 42–45" high (§F2.6.1.2) with no opening that passes a 4" sphere (§F2.6.1.3) — published guidelines, not law. Gangway live load depends on the design basis: 30 psf residential, from Ameren's Appendix B §7.9, which is permit-mandated on Lake of the Ozarks (Tier 1 there) and the only published residential gangway figure we have found; or 100 psf marina, from DBW §F2.2 (Tier 2, a published guideline).
- Who issues a permit for a residential dock?
- Usually three offices, and you need all of them named before you quote: the U.S. Army Corps of Engineers district for the waterbody (Section 10 / Section 404 — the 2026 Nationwide Permits run 2026-03-15 through 2031-03-15, and NWP 2 covers only structures in artificial canals within residential developments, so most new residential docks ride a district Regional General Permit or an individual permit), the state waterway agency (Wisconsin DNR, Minnesota DNR, Florida DEP, Washington WDFW, New York DEC, or TVA on its reservoirs), and local shoreline zoning. Their dimensional caps — pier width, total square footage, distance from shore — shape the dock before any engineering starts.
- Which states’ dock size limits does deckpro.studio check automatically?
- Six authorities, because six are what we have transcribed from the agency’s own document — Wisconsin, Florida and New York from agency PDFs we checksummed, Minnesota, Washington and TVA from the agency’s or the regulation’s published page: Wisconsin DNR under Wis. Stat. 30.12(1g)(f) (exempt pier 6 ft wide, with one loading platform of up to 200 sq ft), Minnesota DNR (no permit where no part exceeds 8 ft wide), Washington WDFW under WAC 220-660-140 (6 ft over the first 30 ft from mean low water in fresh water, 4 ft ramps, and float grounding approved only in reservoirs at drawdown), Florida DEP under Fla. Stat. 403.813(1)(b) and (1)(i) (exempt to 500 sq ft in Outstanding Florida Waters, 1,000 sq ft elsewhere or in an artificially created waterway), NYSDEC under 6 NYCRR 661.5(b) and its tidal-waters guidance DFW-6 (open-pile catwalks 4 ft, floating docks change use class at 200 sq ft), and TVA on its reservoirs under 18 CFR 1304.204 (a 1,000 sq ft siting rectangle, 1,800 sq ft in areas of preexisting development, 150 ft from shore, walkways 6 ft, fixed decks 18–24 in above full summer pool). Record the state and the water body on the measurement and the estimator compares the drawn dock against those numbers, names the office behind each, and lists the clauses it cannot check (grating, channel width, wetland category and the like). For any other jurisdiction it says it has no rules on file and points you at your waterway authority — it does not guess at a cap, and it never tells you the dock is permitted.
See it run on a real dock
The dock studio applies every number on this page as you enter the site — flotation, piles, pipe legs, gangway — and flags the site conditions that will not work, before you quote them.