Room renovation calculator

Estimate outputs: Floor area with allowance, Whole flooring packs, Net wall area, Paint for all coats, Whole baseboard pieces. Adjust Length, Width, Height to match your project.

Inputs and units

Use the units shown beside each field. Replace the sample values with your measurements and the figures on the selected product packaging.

Parameter	Example input
Length	5 m
Width	4 m
Height	2.7 m
Openings area	4 m²
Total doorway width	1.8 m
Floor coverage per pack	2.2 m²
Coverage	10 m²/l
Coats	2
Stock piece length	2.4 m
Waste allowance	8 %

Formula and assumptions

Floor area with allowance
Length × Width × (1 + Waste allowance / 100)

Whole flooring packs
ceil(Floor area with allowance / Floor coverage per pack)

Net wall area
max(0, 2 × (Length + Width) × Height - Openings area)

Paint for all coats
Net wall area × Coats × (1 + Waste allowance / 100) / Coverage

Whole baseboard pieces
ceil(max(0, 2 × (Length + Width) - Total doorway width) × (1 + Waste allowance / 100) / Stock piece length)

ceil = round up; floor = round down; max = the greater value. Trigonometric angles are converted from degrees to radians.

Allowance is applied before rounding to whole packages. Whole units are rounded up; displayed decimals are rounded only for readability.

Project lists use simplified rectangular geometry. They do not include every fixing, fitting, accessory or labor cost.

Worked example

Sample values are examples, not product specifications. Run the calculation again with your own measurements.

Result	Calculation
Floor area with allowance	21.6 m²
Whole flooring packs	10
Net wall area	44.6 m²
Paint for all coats	9.6336 l
Whole baseboard pieces	8

Related calculators

Related tools use separate measurements. Check their inputs before transferring quantities.