How Many Mabati Sheets Do I Need for My Roof?
To find how many mabati sheets you need, divide your roof area by the area one sheet covers after overlaps. A 3-metre box profile sheet covers about 2.3 square metres. A typical 3-bedroom roof of 120 square metres needs roughly 55 to 65 sheets, plus ridges and nails. Use the calculator for an exact figure.
Buying too few sheets means a second delivery charge; buying too many wastes money. Here is how to get the number right, and a free tool that does the arithmetic for you.
The simple formula
- Find your roof area in square metres. This is bigger than your floor area because of the roof pitch and overhang. As a rough guide, roof area is about 1.25 times the floor footprint.
- Divide by the area one sheet covers after overlaps. A 3-metre box profile sheet covers roughly 2.3 square metres once you allow for side and end laps.
- Round up. Always round up to whole sheets, and add a small margin for cuts on hips and valleys.
So for a 120 square metre roof: 120 ÷ 2.3 ≈ 53 sheets, rounded up and with a margin, call it 55 to 65 sheets.
Sheets by house size
| House size | Approx roof area | 3m box profile sheets |
|---|---|---|
| 1 bedroom | ~55 m² | ~24 to 30 |
| 2 bedroom | ~85 m² | ~40 to 48 |
| 3 bedroom | ~120 m² | ~55 to 65 |
| 4 bedroom | ~165 m² | ~75 to 90 |
Longer sheets reduce the number of end-laps and can cut waste on a standard roof. See 3-metre mabati prices.
Do not forget the extras
- Ridge caps for the apex of the roof, usually in 2-metre lengths.
- Roofing nails or screws with rubber washers, roughly 0.3 kg per sheet.
- Valley and barge flashing on hipped or complex roofs.
Let the calculator do it
Rather than estimate by hand, enter your house size, profile and gauge into the free roof calculator. It returns the sheet count, ridge caps, nails and an estimated cost range by factory tier, then lets you send the whole list to us on WhatsApp for today’s real factory price, with no markup.