Spend over £100 (ex. VAT) for FREE Delivery

Customer Support 0800 22 77 77

Near You - Local Branches Nationwide

How Many Composite Slates Do You Need Per Square Metre (m²)?

How Many Composite Slates Do You Need Per Square Metre (m²)?

Calculating the correct number of composite slates for your roof is essential for completing the perfect roofing project. But how do you do this and what factors do you need to consider? This blog aims to answer these questions and more!

What Factors Affect the Number of Slates Per m²?

There are several factors which can affect the number of slates you need per m².

Understanding Slate Sizes and Head lap Coverage

It may sound obvious, but the size of your chosen slate will affect the amount you need to complete your roof. For example, the smaller the slate the more you'll need, and the larger the slate the less you'll require.

You also need to consider the head lap. This refers to the overlap or covering of the upper section of one slate by the lower section of the slate above it. This plays a crucial role in protecting your roof and preventing rain from entering. It is important to factor the head lap into your measurements when calculating how many slates you need.

The Impact of Roof Pitch and Overlap

The pitch of your roof will have an impact on how many slates you need and how they are installed. A steep pitched roof, which is usually found on more traditional homes, allows for better water run-off. This means the slates require a smaller overlap, which in turn will affect the number of slates you need.

As water does not run off a lower pitched roof as well, larger overlaps are...

Anthracite Grey Composite Slates: Modern Aesthetics

For modern homes, anthracite grey composite slates are the perfect partner. Their sleek appearance and contemporary colour blends beautifully with other anthracite grey fixtures and fittings.

Traditional Grey Composite Slates: Timeless Appeal

Traditional grey composite slates emulate the classic look of real slate, making them ideal for period properties.

Slate Blending: Mixing Colours for a Unique Finish

Blending different colours of slates can create a uniquely natural and textured look. This look can work well on both modern and traditional homes.

Tips for Ordering Composite Slates

Mixing Slate Pallets to Avoid Colour Banding

To prevent noticeable colour variations it is advisable to buy your composite slates in one batch, hence why it is so important to calculate the correct number of slates required for your roof. You can also choose to mix your pallets which will result in a range of tones and help prevent colour banding.

Choosing the Right Slate Pattern for Your Roof

There are myriad slate patterns you can choose from. The size and shape of your roof will most likely dictate which designs will work best for your home. Having a chat with a professional will help you find this perfect pattern. If you’re still deciding between options, you might also want to read our guide on Composite Roof Tiles Vs Slate to help make the best choice for your project.

If you're unsure of how many slates you need or would like a chat about your next roofing project, call our friendly, expert team today on 0800 22 77 77.

*Information correct at time of publishing.



National Plastics is a trading name of Specialist Building Products Limited, a wholly owned subsidiary of the Epwin Group. Specialist Building Products Limited is registered in England & Wales. Company Registration number: 1268689. Registered Office: Friars Gate, 1011 Stratford Road, Shirley, Solihull, West Midlands B90 4BN. VAT Registration No. 864 4507 10