Why does this not just tell me what a deck costs?

Because nobody can, honestly. Lumber pricing is regional and moves weekly, so a published figure is stale almost immediately. What is stable is the quantity of material your deck needs, and that is what this page computes.

How much does a 12x16 deck cost?

That depends entirely on your lumber prices, and anyone quoting a single national figure is guessing. This page tells you exactly what a 12 ft by 16 ft deck needs in joists, beam, posts, footings, decking and fasteners. Price those at your yard for a real answer.

Does it include labour?

Only if you enter a labour rate per square foot. There is no default, because labour rates vary more than materials do.

Are the quantities the same as the deck materials calculator?

Yes. Both read the same code tables through the same build-time data, and a build-time check compares them across 75 deck configurations.

Yes. The takeoff is exact, with no allowance. Most builders add 5 to 10 per cent on decking, and more where there are mitres or a picture-frame border.

Why is the frame sized before the price?

Because the frame decides the quantity. You cannot count joists until you know whether the span needs a 2x8 or a 2x10, and that comes out of IRC Table R507.6, not out of a price list.

Home › Decking › Deck Construction Cost Estimator

Deck Construction Cost Estimator

Quantities from IRC R507.6, R507.5(1) and AWC DCA 6 Table 4

Most deck cost pages quote a national average with no source and no date. This one counts the actual materials your deck needs, then lets you price them at your own yard.

Deck cost estimate

Deck width (house out to the beam)

Deck length

Species

Joist spacing

Beam size

Board width (actual)

Gap between boards

Footing depth

Concrete bag yield (60 lb is 0.45, 80 lb is 0.60)

cu ft

Screws per box

Or price decking per sq ft (pre-filled at the midpoint of the $3 to $6 range quoted below)

$/sq ft

Joist price (per linear ft)

$/ft

Beam price (per linear ft)

$/ft

Post price (per linear ft)

$/ft

Decking price (per linear ft)

$/ft

Concrete (per bag)

Screws (per box)

Joist hanger (each)

Labour (midpoint of the $8 to $22 range quoted below, change it)

$/sq ft

Quantities are sized against IRC Table R507.6, IRC Table R507.5(1) and AWC DCA 6 Table 4. Prices are pre-filled from a range another publisher printed, attributed and dated below. Change them to yours.

Specification summary

Generated from on . Reopen that address to reproduce these figures exactly.

Entered

Result

How beam span and joist span are measured

Worked example

A 12 ft by 16 ft deck in Douglas fir-larch, joists at 16 in centres, priced at a yard quoting $2.40 a foot for decking.

The frame is sized first. IRC Table R507.6 gives the joist that spans 12 ft at 16 in centres, and R507.5(1) gives the beam. That decides how much timber there is before any price is applied.
Footings follow the beam. The post spacing sets the Table 4 row, which gives the footing diameter, and the diameter and your depth give the concrete volume in bags.
Then the quantities are counted. Joist linear feet, beam plies, decking rows and linear feet, screws at two per crossing, one hanger per joist.
You supply the prices. Enter what your yard actually charges per foot and per bag. Leave a line blank and it stays a quantity rather than becoming a guess.
The total is arithmetic. Quantity times your price, plus optional labour per square foot, divided by the area for a cost per square foot you can compare against a quote.

The value here is the quantity list, not the total. Two yards forty miles apart will price the same deck differently, and neither of them is the national average a cost article would have quoted you.

The formula

There is no cost formula, because there is no honest cost constant. What there is, is a takeoff multiplied by prices you supply:

cost = Σ (quantity_n × your price_n) + area × your labour rate

quantity: counted from the code-sized frame, not estimated per square foot
your price: what your yard quotes, today, for that item
area: deck width times length, in square feet
: No national average, no regional multiplier, no index. Those are the parts other cost pages invent.

Because the quantities are sized against the same tables as the rest of this site, changing species or spacing changes the bill of materials, not just a label. Wider joist spacing means fewer joists and fewer hangers, and a species change can move the joist size and the whole footing schedule.

Why there are no prices on this page

Because any price printed here would be wrong. Lumber moves week to week and varies by region, delivery and yard. A figure published today is stale within a month, and a stale cost estimate is worse than none: it gets screenshotted and quoted back.

Because the competitors that do publish one will not say where it came from. Several deck cost pages quote a dollar figure with no source and no date attached. There is no way for a reader to check whether the number was gathered last week or invented in 2019.

What is defensible is the quantity. How many joists, how many linear feet of decking, how many bags of concrete: those follow from your dimensions and the code tables, and they do not change with the market. That part this site will stand behind.

So the split is deliberate. Quantities from the code, prices from your yard. Take the list to a supplier, or enter their numbers and let the page do the arithmetic.

Published price ranges, and whether they have aged

If you have no quote yet, the figures below give you something to enter. They are not this site's numbers. They are what decks.com, cost to build a deck publishes, quoted here so you can see them and judge them, read on 2026-09-06.

Cost per square foot, as published by decks.com, cost to build a deck
Item	Low	High
Pressure-treated wood	$3	$6
Cedar	$4	$8
Composite	$5	$14
Redwood	$7	$12
Bamboo	$3	$10
Ipe	$10	$20
Aluminium	$15	$20
Labour	$8	$22

Source: decks.com, cost to build a deck, read 2026-09-06. decks.com gives no source and no date for these figures and does not say which regions or which year they describe.

Whether those figures have aged

Nobody publishes a free, citable per-board retail price. What does exist is the Producer Price Index, softwood lumber from the US Bureau of Labor Statistics, series WPU0811, which is free, dated and revised on a schedule. It stood at 300.614 in July 2026. Softwood lumber is +15.0% against July 2025, so a price published much before then is likely low.

Source: US Bureau of Labor Statistics series WPU0811, read 2026-09-06. An index is not a price: it tracks what producers charge, not what your yard charges, so use it to judge the direction of travel rather than to set a figure.

What the estimate leaves out

The takeoff covers the structure and the deck surface: joists, beam, posts, footings, decking, screws and hangers. It does not include the ledger and its flashing and bolts, stairs and their stringers, guard posts and balusters, joist tape, post bases and caps, concrete tube forms, permit fees, excavation, or removing whatever is there now.

Those are real money on a real deck, and several of them are decisions rather than quantities. Add them from your own drawings rather than letting a page invent them.

Comparing this against a contractor's quote

The useful comparison is not the total, it is the per-square-foot figure and the material line items. A quote well above your priced takeoff is not automatically high: it carries labour, insurance, waste, hardware, permits and profit. But if the materials line in a quote is double the yard price for the same quantities, that is a question worth asking.

Print the sheet and take it with you. It lists the quantities and the code table each member was sized against, which is a firmer footing for a conversation than a number from a cost article.

Frequently asked questions

Why does this not just tell me what a deck costs?: Because nobody can, honestly. Lumber pricing is regional and moves weekly, so a published figure is stale almost immediately. What is stable is the quantity of material your deck needs, and that is what this page computes.
How much does a 12x16 deck cost?: That depends entirely on your lumber prices, and anyone quoting a single national figure is guessing. This page tells you exactly what a 12 ft by 16 ft deck needs in joists, beam, posts, footings, decking and fasteners. Price those at your yard for a real answer.
Does it include labour?: Only if you enter a labour rate per square foot. There is no default, because labour rates vary more than materials do.
Are the quantities the same as the deck materials calculator?: Yes. Both read the same code tables through the same build-time data, and a build-time check compares them across 75 deck configurations.
Should I add waste?: Yes. The takeoff is exact, with no allowance. Most builders add 5 to 10 per cent on decking, and more where there are mitres or a picture-frame border.
Why is the frame sized before the price?: Because the frame decides the quantity. You cannot count joists until you know whether the span needs a 2x8 or a 2x10, and that comes out of IRC Table R507.6, not out of a price list.

Check these numbers yourself

IRC R507.5 and R507.6: deck beams and joistsUpCodes. The span tables that size the frame the quantities are counted from.
AWC DCA 6: Prescriptive Residential Wood Deck Construction GuideAmerican Wood Council, free PDF. Table 4 for the footing schedule.

Figures on this page last checked against the source documents on 2026-09-06. Codes are amended locally; confirm against the edition your jurisdiction enforces.

Related calculators

Estimates only. Quantities are a takeoff from prescriptive code tables for a rectangular ledger-attached deck, with no waste allowance and no ledger, stairs, guard, hardware, permit or site-work costs included. Prices are whatever you enter; this site publishes none. Confirm quantities against your own drawings and prices against your supplier before you buy.