How Many Roofing Sheets Do You Need?

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How Many Roofing Sheets Do You Need?

Roofing sheets are some of the most versatile roofing solutions. Available in a wide choice of materials from bitumen, to metal, to fibre cement, and more. Each of these comes with their own unique advantages and are best suited to different kinds of roofing projects. Whether you’re re-roofing your shed, revitalising your garage or finishing off a lean-to, we’ve got a roofing sheet that’s perfect for you.

One of the most common questions we receive from customers is “How many roofing sheets do I need?”. This can depend on several things, including the size of the sheets themselves, the area you need to cover and the pitch of your roof. That’s why the team here at Roofing Megastore has designed our fantastic range of roof sheet calculators.

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Why Use Roofing Calculators?

Our calculators are incredibly easy to use. All you need to know is the size of your roof and which type of roofing sheet you’d like. The calculators will then work out how many roofing sheets you need, along with all necessary fixtures and fittings. So, by using a roofing sheet calculator, you’ll save yourself plenty of time, as their precise calculations will ensure you order the perfect amount for your project, minimising wastage. Perfect for a homeowner doing a bit of DIY or a busy roofing contractor who’s looking for a way to work out quotes quickly.

What Types of Roofing Sheets Are Available?

Whichever roofing sheet you choose will boast its own series of benefits, and the right one for you depends on your budget and the structure you’re roofing. We’ve got an excellent roofing sheets buyer’s guide which goes into our range in more detail. But if you want to stick around, here’s a quick rundown of the main types available and how to use their calculators:

Bitumen Roofing Sheets

Bitumen roofing sheets are a highly versatile, lightweight and long-lasting option. They can withstand extreme weather conditions including rain, hail, and wind, and offer brilliant thermal insulation as well as sound absorption. A bitumen roofing sheet can last for many years with minimal maintenance, which makes them a popular choice for sheds, garages, and more.

Bitumen roof sheets are incredibly tough yet can be cut to size quite easily using a fine-toothed hand saw. This makes them a fantastic choice for garden projects or even for agricultural buildings such as stables. The easy installation of bitumen roofing sheets makes them ideal for both DIYers and tradespeople. Plus, these sheets can be used on roofs with pitches from 5° all the way up to 90° and come with a 15-year waterproof guarantee.

How to Use the Bitumen Roofing Sheet Calculator

We’ve built calculators for two of our most popular bitumen roofing sheets, including Stradia and Coroline sheets. Follow the steps below to learn how to use them.

  1. First, click the grey ‘Roofing Calculator’ button on the product page just above the green ‘Add to Cart’ button.
  2. Then, you’ll arrive at the ‘Choose Your Roof’ section. You’ll see some helpful diagrams showing Apex, Lean-To and Single Slope roofs. Choose the one that most closely resembles the roof you’re working on.
  3. Next, enter the width and length of your roof. There should be a dropdown to switch between metric and imperial measurements here, depending on which you prefer.
  4. The next page should show you how many roofing sheets you need, along with any necessary fixings and accessories.
  5. Finally, select the colour you’d like on the right-hand side (or underneath if on mobile).

Be sure to double-check the products and quantities our calculator has suggested before adding them to cart. This whole process should take less than a minute, giving you more time to focus on your project!

Polycarbonate Roofing Sheets

Polycarbonate sheets are one of the most widely used roofing materials around! These extremely versatile sheets are fantastic for many garden projects, from greenhouses to cold frames, right through to conservatories! Polycarbonate roofing is incredibly easy to handle, cut, and install, and comes in a range of thicknesses and colours.

Polycarbonate sheets are a common choice for DIYers due to their ease of use, often for allotments, garden buildings and lean-tos. Contractors favour polycarbonate due to its light transmission and high levels of UV protection. In fact, polycarbonate sheets have even been used at the Etihad!

Clear polycarbonate is ideal for greenhouses and pergolas due to the high amount of light that passes through, whilst bronze helps to keep glare at bay and keeps heat inside due to high levels of absorption. We’d recommend an opal finish for increased privacy, as well as reducing solar energy entering the sheet, great for carports as it will keep the covered area cooler.

Generally, when choosing multiwall polycarbonate, the thicker the sheet the stronger it is. Our range goes from 4mm sheets all the way up to 35mm sevenwall polycarbonate. 25mm polycarbonate is ideal for conservatories, while 16mm polycarbonate is most useful for greenhouses. 10mm twin wall polycarbonate is ideal for lean-tos, cold frames, cloches, and other small scale garden projects.

With polycarbonate, the thicker the individual sheet the stronger it usually is, so of the different

How to Use the Polycarbonate Roofing Sheet Calculator

We’ve designed calculators for use with one of our most popular polycarbonate sheets, Corotherm.

  1. Once you’re on the product page, click the grey ‘Roofing Calculator’ button you’ll find just above the green ‘Add to Cart’ button.
  2. Now it’s time to select your roof type. Take a look at the helpful diagrams and choose the one that matches the roof you’re working on.
  3. Once you’ve chosen between apex, lean-to and single slope roofs, it’s time to pick the colour and thickness of polycarbonate sheet you want.
  4. Next, enter the length and width of your roof. You can do this in either inches or centimetres, using the dropdown to select whichever you prefer.
  5. Now, choose the size of sheet you think best suits your project.

Our calculator should now present you with how many roofing sheets you need, along with all necessary fixings, flashings and accessories. Read our blog to discover what goes into a full polycarbonate roofing system. We’d recommend double-checking everything before you continue to your basket.

Corrugated Metal Roofing Sheets

Few roofing materials offer greater levels of strength and longevity than metal corrugated roofing sheets. A brilliant choice for agricultural and commercial buildings, metal sheets are often seen adorning equestrian stables, livestock barns, warehouses, and more. They’re even seeing increased use in micro homes and even interior design!

These sheets are incredibly strong thanks to their galvanised steel construction, and will protect your roof from all weather conditions, temperatures, and unexpected impacts. You even have the choice to further reinforce their durability through scratch- and fade-resistant coatings made from PVC plastisol.

With metal sheets, you can choose between 0.5mm and 0.7mm thicknesses, with the thicker varieties being slightly stronger. We’d recommend 0.7mm sheets for larger projects such as stables or barns, whilst 0.5mm sheets are ideal for smaller structures like sheds or lean-tos.

How to Use the Corrugated Metal Roofing Sheet Calculator

We’ve built calculators for some of our most popular metal roofing sheets. These include galvanised steel corrugated roofing sheets, and the iconic Corotile tile effect roofing sheet.

  1. Click the grey ‘Roofing Calculator’ button just above ‘Add to Cart’ on a product page.
  2. Next, choose the type of roof that most closely matches yours. If you’re unsure, consult the image guides.
  3. Now input the length and width of your roof in either metric or imperial measurements. Use the handy dropdown to switch to the one you prefer.
  4. Then, select the thickness of corrugated metal sheet you’d like. Remember that thicker sheets are stronger but more expensive.
  5. Finally, choose the colour and finish you’d like for your roof.

Once you’re done, our corrugated roofing calculator should now show the exact number of roofing sheets you need, along with all necessary fixings to complete your project. Double check everything before you order.


And there you have it, our most popular roofing sheet calculators explained! If you’re still unsure about anything, don’t hesitate to get in touch with our award-winning customer service team. They’re on hand to help you with any questions you may have. Call them on 01295 565 565, email [email protected] or use our handy online live chat.

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