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Multi-room Material Calculator

Measure up to 20 rooms. Pool paint, flooring, tile and drywall requirements before rounding shared product packages once.

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01 / YOUR ROOMS
Input & display units
Up to 20 rectangular rooms.

Shared products for the whole project

These editable product values are examples. Replace them with your actual labels before ordering.

Materials to estimate

Flooring and tile may be alternatives. Select both only if you intend to estimate both finishes.

Paint
Optional
Flooring
Optional
Optional
Tile
Optional
Drywall

THE METHOD

How to use this estimate

  1. Add each rectangular room with its own height, doors and windows. Openings reduce wall area, never floor area.
  2. Select the materials you need, then enter one shared product per material. Use separate projects for different paints, tiles, panels or allowance choices.
  3. The project pools unrounded room quantities before purchasing whole containers, boxes or sheets. Buying each room separately can give a different, larger package count.
  4. Room labels stay on this device. Shared links carry measurements and product assumptions without labels. Anyone with a link can read those quantities.
FORMULA / ENGINE VERSION 1.0

total floor = sum(room floor); total net walls = sum(room net walls); packages = ceil(pooled material requirement / shared package coverage)

A worked example

Two rooms measure 4 × 5 × 2.5 m and 3 × 4 × 2.5 m. Each has one 0.9 × 2.1 m door; the first has two 1.2 × 1.2 m windows and the second has one. Total floor = 32 m²; net walls = 71.9 m². Two paint coats at 10 m²/L need 14.38 L, or six 2.5 L containers. Flooring with 10% allowance needs 18 boxes at 2 m²/box. Walls-only drywall, one layer and 10% allowance, needs 28 panels of 1.2 × 2.4 m.

Project floor area: 32 m² / 344.445 ft²
Paint containers
6
Flooring boxes
18
Drywall sheets
28

Why pooling changes the shopping list

For two rooms needing 1 m² of drywall each, a shared 1.2 × 2.4 m panel covers 2.88 m². Pooling the 2 m² requirement gives one panel. Rounding each room separately gives two. This comparison assumes usable shared coverage; actual cuts and seams can still require more panels.

Questions, answered

Can rooms use different products?

This project assumes the same product and allowance for each selected material across all rooms. Use separate projects when products or allowances differ.

Are flooring and tile a combined order?

They can be alternative finishes. Select both only when you intend to estimate both quantities; this tool does not assign different floor finishes to individual rooms.

Does this optimize cuts or certify a construction plan?

No. It pools physical quantities and purchase packaging. Cuts, assemblies, local rules, safety and structural design require separate verification.

Sources and product assumptions

These references explain units or product specifications. Your selected product label takes priority; none of these sources endorses this calculator.