Project tools
Cladding Estimator
Estimate board counts, linear metres, and fixing quantities for common timber cladding profiles.
Quick start
- Measure one representative wall footprint (width × height) in mm; multiply by number of similar walls, or rerun per elevation if they differ.
- Pick the profile that closest matches merchant listings (overlap rules differ feather vs square edge below).
- Enter board nominal width and overlap—the calculator converts to horizontal effective cover.
- Choose stocked board lengths; we round rows up assuming boards run horizontally (rotate assumptions if cladding vertically—see sidebar).
What each thing means
- Wall width / height
- Per wall plane in mm. Tool assumes rectangles; deduct major openings mentally or reduce height if simplifying.
- Number of walls
- Counts identical elevations. Multiply area internally—don't sum unrelated shapes without tweaking dimensions.
- Board width & overlap
- Board width exposes face minus overlap feather-style; other profiles subtract overlap differently—feather subtracts overlap from cover spacing.
- Waste %
- Adds trim cutoffs, breakage, rejects. Raise for complex cuts/ladders; minimal for machined packs.
- Cladding profile dropdown
- Only changes suggested fixings density per m²; swap profile if estimating screws/nails bundles.
- Board length
- Stock length dictates courses per elevation—longer packs reduce butt joints horizontally.
Configuration
Put wall sizes before worrying about trims—everything here is cladding field area only.
Results
Total boards
212
Wall area
38.40 m²
Effective cover
100mm
Linear metres
508.8m
Fixings
254 screws
Get better results
- Add 10–15 % waste domestic builds unless supplier already includes cutting allowance.
- Check wind zone & batten spacing with your specifier—don't treat fixing count as BS 5534 replacement.
- If boards run vertically, reinterpret width ↔ height mentally or rerun swapping dimensions.
- Feather-edge overlap affects weathering shadow lines—overlap shown is horizontal coverage only.
- Buy last pack unopened if hovering near multiple—returns easier than scrambling mid-job.
Reading the numbers
Board count is ceilings of rows × boards per row × walls with waste uplift. Effective cover exposes how aggressively overlap eats face width. Linear metres multiplies stocked length by board count rounded up (not optimised for nesting cuts).
Not a substitute for structural sign-off
Indicative retail planning numbers only—supplier pricing, rebates, trims, membranes, cavities, breathable membranes, corrosion class fixings ignored. Obtain structural / fire / warranty sign-off externally.