How Many Roofing Sheets Do I Need? Roofing Calculator Guide for Kenya (2026)

Oct 04, 2026

Buy More Mall Kenya

Ordering the right amount of roofing saves money and avoids delays. Here is how to calculate box profile or iron sheets for a simple roof, with current prices from Lets Construct.

Boxprofile/IT5 30G(STH) – price in Kenya — Boxprofile/IT5 30G(STH)
**KSh 430**

Boxprofile/IT5 G28(STH) – price in Kenya — Boxprofile/IT5 G28(STH)
**KSh 600**

Boxprofile/IT5 26G(STH) – price in Kenya — Boxprofile/IT5 26G(STH)
**KSh 850**

Classic Type Decra Stone Coated Tiles – price in Kenya — Classic Type Decra Stone Coated Tiles
**KSh 750**

Step 1: Measure the Roof

Roof length along the eaves (each side).
Rafter length from ridge to eaves, plus the overhang (often 300–450 mm).
For a simple gable roof there are two equal sides.

Step 2: Sheets Across Each Side

Number of sheets per side = roof length ÷ effective cover width of the sheet, rounded up. The effective cover width is less than the full sheet width because sheets overlap; confirm it for the profile you choose (ask the seller), as profiles differ.

Step 3: Sheet Length and Total Metres

Box profile is sold per metre and cut to length, so each sheet = rafter length + overhang. Total metres = sheets per side × sheet length × number of sides.

Worked Example (Illustration Only)

Item	Value
Roof length per side	12 m
Rafter + overhang	4.5 m
Effective cover width (example)	0.76 m
Sheets per side	12 ÷ 0.76 = 15.8 → 16
Total metres (2 sides)	16 × 4.5 × 2 = 144 m
Add about 5% for cutting	≈ 151 m

Replace the cover width with the real figure for your sheet before ordering.

Box Profile Prices (per Metre)

Sheet	Gauge and finish	Price
Boxprofile/IT5 30G(STH)	30 gauge, standard	KSh 430
Boxprofile/IT5 30G(FLO)	30 gauge	KSh 480
Boxprofile/IT5 30G(MATT)	30 gauge, matt	KSh 580
Boxprofile/IT5 G28(STH)	28 gauge, standard	KSh 600
Boxprofile/IT5 28G(MATT)	28 gauge, matt	KSh 700
Boxprofile/IT5 26G(STH)	26 gauge, standard	KSh 850

Gauge: a smaller number is thicker. 30 gauge is lighter and cheaper; 28 and 26 are stronger and last longer, better for wind and long spans.

Stone-Coated Tiles

Tile	Price
Classic Type Decra Stone Coated Tiles	KSh 750
Shingle Type Decra Stone Coated Tiles	KSh 800

Decra-type tiles need roughly 2.2 tiles per m² (approximate; confirm with the supplier). See Decra Roofing Tiles Price.

Do Not Forget

Accessory	Price
Mabati Nails	KSh 240
Roofing Rubbers (Black)	KSh 100

Also plan ridges, gutters and timber. Gutters: Gutter Price.

Not sure which one fits? Send us your details on WhatsApp or through the product page and we will help you choose.

Frequently Asked Questions

How do I calculate roofing sheets?

Divide the roof length by the sheet's effective cover width for the number of sheets per side, multiply by the sheet length and the number of sides, then add about 5% for cutting.