Renovimo
Solid hardwood boards being nailed down across a floor

Hardwood floor calculator

Hardwood flooring calculator:
boards, cleats and cost

Solid hardwood is nailed down, so the fasteners follow the runs of board rather than the size of the room. Get square feet with racking waste, running feet of board, the cleats a nailer actually fires, and rosin paper underneath.

Enter measurements

Room measurements

One room at a time — the rows only land the same way inside a single room. Flooring several rooms? Work them out one by one and order every box together: colour drifts between production batches, and a top-up bought later rarely matches what is already down.

Areas the floor does not reach

A hearth, an island or a built-in the boards stop at — each measured on its own, and placed where it actually stands.

Positions are measured from the back-left corner of the room, as you look at it in the preview.

Exclusion 1
Exclusion 2
Exclusion 3

How the floor is built

Board and waste

The board width drives the running feet, the fastener count and how much the floor is likely to break in handling. Cutting waste is worked out from the cut pattern.

Doorways

One transition strip per opening, where the floor meets whatever is next door. Say which wall each one is in so the preview breaks the trim in the right place.

Doorway 1
Doorway 2
Doorway 3
Doorway 4

Edges

Optional

What will it cost?

Every material the calculator worked out gets its own price. Each field starts at a typical US figure so you have something to work from — change any of them to what your own supplier charges.

These prices are approximate. They are national US retail figures, and what you actually pay varies with your region, your supplier, the season and how much you buy at once. Treat them as a starting point, not a quote — always price the job from your own supplier's current figures before you order.

Your prices

Hardwood boards beside a flooring nailer and mallet

Based on your result

What you'll need

Quantities update after every calculation. Cleats and paper only appear for a nail-down floor.

Hardwood boards
Square feet including racking waste
Calculate above
Cleats or staples
Along every run, plus two at each board end
Rosin paper
Rolls under a nailed floor
Transition strips
One per doorway
Flooring nailer
Pneumatic, hired by the day
1 tool

The maths

How this hardwood floor calculator works

A nailed floor is fastened along its runs, not across its area — so the board width, not the room, is what decides how many cleats the nailer fires. Narrow the board and the running feet climb; the fasteners climb with them.

running board = floor area ÷ (board width ÷ 12)
boards = ⌈ running board ÷ board length ⌉
positions = ⌊ (board length − 4 in) ÷ 8 in ⌋ + 1
cleats = boards × positions × 2 edges
order area = floor area × racking waste
+10%
2 1/4 in strip
+8%
3 1/4 in plank
+5%
5 in wide plank
  1. 01

    Measure the footprint

    Each room is added together and each exclusion comes back out, measured on its own.

  2. 02

    Lay the rows and cut the tails

    The boards run in one continuous beat across the room. The tail of each row is cut, and the piece left over starts a later row — so the real cutting waste comes out of the plan rather than a percentage picked off a list.

  3. 03

    Convert area to running board

    One running foot of board covers its own width, so a 2 1/4 in floor buys more than twice the feet a 5 in floor does.

  4. 04

    Fire the cleats in pairs along each board

    A fixing down each edge at every position, stepping every 8 in from a couple of inches inside one end to a couple inside the other. Closer than 6 in splits the board; wider than 10 in lets it cup.

  5. 05

    Roll out the rosin paper

    Under a nailed floor only. It stops the boards squeaking on the subfloor and slows moisture coming up from below.

Good to know

Hardwood questions, answered

A 12 by 12 room is 144 sq ft. Racking waste depends on the board: about 8% for a 3 1/4 in plank gives 156 sq ft to order, while a 2 1/4 in strip wants 10% and a 5 in wide plank only 5%. Buy it all in one order — boards from a later batch rarely match in colour.

Solid is one piece of timber and can be sanded back four or five times, so it outlives everything else on this site. It has to be nailed to a wood subfloor and hates damp. Engineered is a real wood wear layer on a plywood core: it is stable enough to float or glue over concrete and below grade, but you get one or two sandings at most.

There is no such figure, and that is the point. Fixings follow the boards, so the answer depends on board width. A 7 ft board takes 11 positions at 8 in apart and a fixing at each edge of every position — 22 a board. A 200 sq ft room in 5 in plank runs to about 1 500 of them; the same room in 2 1/4 in strip needs more than twice that, because a narrow board means far more boards for the same floor.

Solid nail-down cannot: there is nothing to nail into and the slab moves moisture. Engineered can, either floated over a pad or glued down, provided the slab is dry and flat. Test the slab for moisture first — a calcium chloride or RH probe test — because a floor laid on a damp slab will cup.

Three to five days stacked in the room it will live in, with the heating running as it normally would. Wood takes up and gives off moisture until it matches the air around it, and a floor laid before that settles gaps in winter or buckles in summer.

Perpendicular to the joists is the structural answer for a nailed floor — it gives every board several fixing points. Where the joists allow a choice, run the boards along the longest wall or towards the main light.

Under a nailed floor, yes. It is cheap, it stops the boards squeaking against the subfloor as they move, and it slows moisture rising from a crawl space. It is not a vapour barrier and it does nothing for a floating or glued floor, so the calculator drops it for those.

Keep estimating