Want to know how many slates your project needs?

Our new calculator gives you everything you need to install a natural slate roof. From slate quantities to batten spacing, nailing, and holing details — all in just a few clicks. Your complete slate roofing estimate!

Complete Slate Roofing Calculator

This calculator follows BS 5534, the UK industry standard for slate roofing, ensuring both accuracy and compliance.

Simply enter your project details to calculate everything you need to know about your natural slate roof. In just two clicks, you’ll get the number of slates required and the weight per square metre.

If you need more details, a Fixing Specification Document will be available to download at the end of the process.

Region:

Select the region.

Pitch:

Select the pitch of the roof.

Slate Size (mm):

Select the size of the slate.

Thickness:

Select the thickness of the slates

HeadLap:

Select the headlap.

While this calculation is based on recognised standards, it is intended as a guideline only. Every roof is unique, and actual requirements may vary. We strongly recommend consulting with us or a qualified roofing professional to confirm your project’s exact needs.

If you have any questions, our experienced team on slate is at your disposal.