Best Roofing Material for Flat Roofs

January 16th, 2015


Though more typical for commercial structures, it is not uncommon for homes to feature flat roofs.  Still, homeowners tend to know very little about roofs in general, much less flat roofs.  In fact, when it comes to roofs, homeowners are typically only interested in one factor: aesthetic.  Pitched roofs are certainly the standard for residential structures, but flat roofs are actually less expensive to install and are therefore a common choice for homes in North America.  If you have a flat roof or you’ve chosen a flat roof for your new home, the obvious question is what is the best roofing material for flat roofs?

Essentially, there are three varieties of flat roof: felt, ethylene propylene diene terpolymer (EPDM), and fibreglass.  So, let’s take a closer look.

Felt (aka Torch On)

Sometimes known as a felt roof, polyester reinforced, or torch on flat roof have come a long way in the last couple of decades.  In the past, bitumen felt roofs were criticized for poor flexibility and durability, but these roofs have improved considerably in the past few years.  Usually applied with a 3 layer system, felt roofs feature a vapour control layer, 2mm of reinforced felt, and a final layer of 4mm felt cap sheet.  This final layer of torch on roofs may be plain black bitumen, solar reflective finish, or mineral fleck finish which is available in a range of colours.

Felt roofs are generally guaranteed for 10 years, but some contractors may offer guarantees of up to 20 years.  That being said, it’s not unheard of for a well-installed torch on roof to last up to 30 years if it is properly maintained.  Easily the cheapest option with respect to flat roofs, felt roofs are a great choice for the budget-conscious. 


EPDM is a fancy way of saying rubber.  EPDM roofs have become increasingly popular since they were introduced in the UK a few years ago.  Often installed in one layer, EPDM roofs can eliminate the need for joins thereby reducing the risk of leaks.  These roofs are very light weight, flexible, and durable and make a great choice regardless of the climate in your region. 

In fact, EPDM roofs are very tough and guarantees can last up to 50 years, and their cost is not prohibitive.  Though, you should expect to pay about 20% more for an EPDM roof than a felt roof.


Sometimes known as glass-fibre reinforced plastic (GRP), fibreglass roofs are by no means new, but they definitely represent the most advanced technology in flat roofs.  With modern resins and proper installation, fibreglass flat roofs are highly resistant to damage and can be repaired very easily.  The main benefit of fibreglass roofing systems is their appearance, but they also tend to be the most expensive.  Guarantees on fibreglass roofs are usually for around 25 years, but can last much longer than 30 years when they are installed properly.

Ultimately, determining the best material for flat roofs depends on a number of factors, including your budget and aesthetic preferences.  Likely, EPDM roofs offer the best bang for your buck, but you should probably discuss your options with a qualified roofing professional.  


Residential roofing: 

Commercial roofing: