Leaking flat roof damaging leaks 
The roof above this ceiling is leaking and damaging the interior.

As has been said before on this blog and many others: flat roofs leak. It is a fact of life that if you have a roof over your head, there is probably a leak somewhere or there will be in the future. This becomes even more of a guarantee if your roof is flat or close to it, because water doesn’t run off of the roof surface as quickly and is able to find breaks in the roofing surface. At Progressive Materials, we have a little saying: “There are only three certainties in life – death, taxes, and roof leaks.” Before we look at your flat roof replacement options, we should start with what causes the leaks. The first step in fixing a problem is to understand it.

What Causes Flat Roof Leaks?

There can be several reasons your flat roof leaks, and each of them can strike in almost any situation. While there are many different causes of leaks, there are three that we have identified as the most common and most detrimental to your building’s performance. These three causes are: 1) Being located in a harsh environment, 2) Standing water on the roofing surface, and 3) Utilizing outdated roofing technology. If your building is in a location with harsh weather and great temperature extremes, your building will experience wear and tear from the elements and there isn’t a lot you can do. However, if you have standing water, there are some ways you can remedy the problem. Finally, if your roofing system technology is outdated, you can fix the problem but you will certainly have to put up some money to do so. If you analyze your roofing system and find that you have outdated technology, don’t stop reading here. Below you will see several flat roof replacement options for a leaking or outdated roof.

Flat Roof Replacement Options

There are many ways you can replace your flat roof, and we won’t go into detail of all of them here. We will do a quick overview and if you’d like to learn more, check out our pages detailing each roof type.


Metal has been used on flat roofs for many decades, and it has proven that it is durable and can last about 35 years. Much past the 35 year mark, though, and you’ll start to see problems with the roof. Traditionally, metal roofs have been built out of terne – which is tin-steel alloy – or copper. These materials have almost entirely been abandoned by the roofing industry and replaced with aluminum. If you replace your leaking flat roof with a metal roof today, you will most likely get an aluminum roof that will last around 3 decades. There are many more details about metal roofs you should know before making a decision.


These two roof types are very similar, and while there are subtle differences, it is safe to talk about them together without confusion or misinformation. EPDM has grown to be the most common commercial flat roof choice in the US thanks to its inexpensive price tag, quick installation, and a very long life expectancy. One aspect building owners love about this roof type is the “green” nature. These roofs are made from recycled materials and have an extremely long lifespan, which makes them easy on the environment.

Built-up Roof

Built-up Roofs, also known as BUR, are a hot tar and gravel roof system that has been around for ages. This roofing material is less expensive than the other materials already covered and is a great fire retardant. However, it also has some drawback. BUR are extremely heavy, and often requires reinforcing the roof structure prior to installation, which is an extra expense and delay that adds very little value.

Modified Bitumen

Modified Bitumen roofs are very similar to asphalt roofs, but they have polymers added into the system that provide added protection and an extended lifespan. These roofs are often rolled on to the roof surface and then heated with a blowtorch. While this creates a good seal, it is dangerous and has led to the burning of more than a few buildings during installation. Modified bitumen is environmentally friendly thanks to its reflective nature.

Spray Applied Coating

There are many different spray applied coatings that have been designed for any application you can think of. Coatings are great flat roof replacement options because they can be directly applied to the roofing surface. Flat roofs have three main options for their coatings: silicone, acrylic and aluminum coatings. These coatings are liquid applied directly onto the roof surface and then cure once in place. This allows for seamless installation that helps to fight leaks. Each of the three coatings has different strengths and weaknesses associated with it, so you’ll need to look at your current roof substrate and determine what aspects are most important to you prior to making a purchase decision.


If you’ve got a flat roof, you’ll more than likely experience le aks at some point. When that time comes, or when your roof is simply old and worn out, you have to decide how you will replace your roof. The key is to first understand your problem and the severity of it, then you need to understand your current roof substrate, hone in on exactly what your roofing needs are, and then do thorough research of the alternatives and decide which you would prefer.