Question 1

What is a typical roof pitch in the UK?

Accepted Answer

Most new build homes in the UK have a roof pitch between 40 and 50 degrees. Older properties, especially those with slate roofs, can have pitches as low as 25 degrees. Our calculator accommodates a wide range of pitches to suit any project.

Question 2

How much wastage should I add for tiles and slates?

Accepted Answer

We recommend adding 10% for wastage as a standard. For complex roofs with multiple hips, valleys, or dormers, you might consider increasing this to 15%. For simple gable roofs with machine-made tiles, 5-7% may be sufficient.

Question 3

What's the difference between a gable and a hip roof?

Accepted Answer

A gable roof has two sloping sides that meet at a central ridge, with flat, triangular walls (gables) at each end. A hip roof has four sloping sides, eliminating the need for gables. Hip roofs are generally more complex and require more materials.

Question 4

Do I need roofing felt or a breathable membrane?

Accepted Answer

Yes, modern UK building regulations require a breathable membrane (often called roofing felt) to be installed under the tiles and battens. This acts as a secondary barrier against wind-driven rain and snow, while allowing water vapour from inside the house to escape.

Question 5

How are roofing battens spaced?

Accepted Answer

Batten spacing, or 'gauge', depends on the type and size of the tile or slate. For standard concrete interlocking tiles, it's typically around 330mm. For plain clay tiles, it's much smaller, around 100mm. Natural slates vary depending on their length. Our calculator uses typical spacings for its estimates.

Question 6

Are these material prices accurate for 2026?

Accepted Answer

The prices used are based on typical UK supplier costs in late 2025 and projected for 2026. However, they are for estimation purposes only. Prices can vary significantly based on your location, supplier, and the quality of the materials. Always get a detailed quote from a local builders' merchant.

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