Studio Matrx Monthly · Volume 1 · Issue 2 · July 2026
Amogh N P
 In loving memory of Amogh N P — Architect · Designer · Visionary 
← The Roofing Knowledge Hub

Waterproofing Material Calculator

Estimate how much waterproofing material a roof or terrace needs — and roughly what it costs. Pick the system, set the area and coats, and get an indicative quantity and cost range. Surface preparation and application are a licensed contractor’s job — treat this as a planning frame, then confirm with local quotes.

100 m² (1076 sq ft)
2

Most liquid systems want 2 coats, cross-applied.

10%

Allow for uneven surfaces, corners, upstands and sheet laps.

Material to buy
0 kg

at ~1 kg/m² per coat × 2 coats + 10% wastage

Material cost
12,10026,400
material only, indicative
Supply + lay
12,00030,000
finished, 100

Brush/roller coating for terraces. Cheap and easy to recoat; UV-tolerant; needs a sound, dry, primed slab. The single biggest driver of success is surface preparation, not the tin you buy — a great membrane over a damp, dirty or ponding slab still fails.

An indicative estimate only. Consumption rates and prices are broad 2026 figures that vary with brand, substrate condition, film thickness, detailing at upstands and drains, site access, scale and the local market — and they change over time. Always follow the manufacturer’s datasheet for coverage and coats, and get written local quotes. Waterproofing application and any work at height are qualified professional work.