Generally speaking, a flat roof has a longer life expectancy than a pitched roof assuming all other variables are the same. Flat roofs are typically more economical in terms of installation, material, and maintenance costs, but as any flat roofed building owner will tell you, they do require a degree of upkeep.

A residential roofing company will typically provide a flat roof warranty of around 10 to 20 years, but it’s not uncommon to get upwards of 25 years out of a well-built and well-maintained flat roof. Pinpointing exactly how much life you can expect to get out of your roof is, of course, impossible. There are countless variables that can affect that figure (climate, type of flat roof, maintenance regimens, etc.).

Types of Flat Roofs

While we can’t tell you definitively how long your roof will last, we can instill some flat roofing knowledge just so you have a better idea of what to expect and when it might be time to start pricing out new roof options. And one of the biggest variables when it comes to flat roof life expectancy is the type of flat roof you choose for your home or building. Here are a few of the more common options used today:


A BUR roof (or “built up roof”) is made up of layers upon layers of bitumen and fabrics. BUR roofs provide excellent insulation as well as protection from the elements. Generally, a BUR roof will last around 15 years before signs of age and damage become apparent.


If longevity is a necessity, you can’t go wrong with a PVC (polyvinyl chloride) roof. A PVC roof is completely water resistant and provides excellent protection from even the most abrasive climates. It is not uncommon for a well-constructed PVC roof to last upwards of 30 years. 


Ethylene propylene diene monomer (EPDM) roofs are comprised of rubber membranes which allow for optimal insulation and protection. EPDM roofs are often the preferred choice in climates prone to hail storms. A well-built EPDM roof will last upwards of 20 years regularly.


A thermoplastic polyolefin (TPO) is a relatively newer option for flat roofs. These roofs are made from a single-ply membrane with polymer fillers for added strength and durability. These roofs provide maximum protection from harmful UV rays and typically last anywhere from 15 to 30 years.

Spray On Coating

A spray polyurethane foam coated roof is made up of three layers and can provide superior protection from wind, UV rays, and other harmful elements. In terms of cost, spray-on roof coatings can cost substantially more. However, when properly maintained, a spray-on coated roof can last decades.

Modified Bitumen

A modified bitumen roof is extremely durable and do not typically require much maintenance at all. A modified bitumen roof is completely water resistant and provides adequate protection from sunlight and harmful elements. A modified bitumen roof installed properly can last upwards of 20 years easily.

Remember, all of these life expectancies are merely estimates. While there’s nothing you can do to control the weather in your region, you should call upon a professional team to inspect your roof from time to time (especially after bad storms) just to ensure that everything looks right. Catching and fixing problems early on can be the difference in getting 10 years or 40 years out of your flat roof.

To know which flat roof is right for you, you’ll want to consult with a professional roofing company like CWC Roofing. Our roofing experts can survey your property and provide an extensive list of pros, cons, and pricing options for your flat roof.