Why Are Roofing Sheets Corrugated?

What Is Corrugated Bitumen?

Corrugated bitumen is a brilliant choice for a wide range of applications from sheds, garages and summer houses to stables and agricultural buildings.

It’s made from bitumen saturated organic fibres which make it an incredibly strong roofing material, this coupled with it’s ease of insulation is the reason why Bitumen roofing sheets are one of the top selling roofing materials for garden buildings.
Bitumen sheets also boast good insulation and sound absorbency qualities as well as an expected lifespan of 15 years. Plus, you can use these roofing sheets with most commercially available constructions materials making It a brilliant DIY choice.

Why Are Bitumen Roofing Sheets Corrugated?

Bitumen sheets have uniform corrugations across their breadth and there are a number of advantages that these corrugations give the sheets which make them more effective than a flat roofing sheet:

1. Corrugations Make Roofing Sheets Stronger

One of the biggest advantages corrugated sheets have over flat sheets is the extra strength the corrugations give them. Adding rigidity along the entire length of the corrugations and strength in bending, the sheets are prevented from sagging. Ensuring that there are regular supports on your roof to support the sheets will ensure that your roof remains strong and rigid.

2. Corrugated Sheets Drain Water More Effectively Than Flat Sheets

The corrugations allow for quick and easy drainage of rainfall straight off the roof. This method is so effective that Ariel Plastic’s corrugated Coroline roofing sheets are guaranteed waterproof for 15 years.
Bitumen roofing sheets must always be fitted at a roof pitch of at least 5 degrees (and anything up to 90 degrees!) to allow for easy drainage.

3. Corrugations on the Roofing Sheets Allow for Expansion and Contraction

Most roofing sheets will expand or retract with changes in temperature, this is completely normal and will happen on a day to day and seasonal basis, however, these expansions and contractions can be the main cause of roof leaks, the corrugations in bitumen sheets resolve this issue. The corrugations have space for the movement to happen and so the material is not damaged in any way during the process and will remain leak free.

4. They Stop Rainwater Seeping Through

Because Corrugated Sheets are fitted with the holes drilled through the crown of the corrugations there is less chance of rainwater seeping through the roof.

5. They Look Better Than Plain Sheets

Many people prefer the aesthetics of a corrugated sheet which can look much more elegant and more expensive than a flat roof (even if it isn’t!).

They also come in a choice of colours including red, green, brown or black and so are perfect if you want to match your roofing colour to that of another building or make the roof blend into the landscape.

How Do You Fix Bitumen Roof Sheets?

Roofing Sheets are one of the quickest roofing materials to fit, they’re light, weighing approximately 5.5kg per sheet, and easy to handle.
The sheets can simply be overlapped on the sides and ends reducing the amount of cutting required dramatically and if any cutting is required then this can be done easily with a coarse toothed hand saw or a power saw. The sheets are then easily fixed in place using purposely designed fixings.

Corrapol Rock n’ Lock Verge side flashing provides Corrapol Bitumen sheets with a weatherproof finish and will prevent the sheets from separating. They’re extremely easy to fix, and as the name suggests, they can be simply rocked on and then locked into place.

More Information

If you have any questions or would like any further information about Corrugated Roofing Sheets or Corrapol Rock n’ Lock Verge then call Roofing Megastore’s friendly customer service team on 01295 565565, email us or talk to us via the live chat on our website.