After being relegated in preference for Asphalt Composite Shingles, metal roofing panels are steadily becoming…
Residential flat roofs help you achieve a modern and minimal look. They might or might not be the most pleasing of the lot, that depends, but no one can disregard the obvious advantages they come with. If you are also looking into flat roofs for your home, then here’s everything you need to know about all types of them.
There are three major types of residential flat roofs:
- Built-up roofing or BUR
- Modified Bitumen Roofing
- Single-ply Membrane
Single-ply Membrane roofs can be further categorized based on the material used, such as PVC, TPO, and EPDM.
Let’s learn about these types of residential flat roofs.
Built-up roofing or BUR
Tar and gravel BUR-style roofing is perhaps the oldest and most standard type of flat roofing. It’s what comes to mind when we think of flat roofs. It’s becoming less and less likely to spot BURs on residential properties thanks to the advent of other kinds of flat roofs, though BURs are the go-to roof style when it comes to commercial buildings.
In this type of roof, a layer of roofing felt is covered with hot asphalt. Generally, BURs are a set of 3-5 layers. Each layer adds another few years to the lifespan of the roof. Multi-layer BUR protects homes from UV radiation while improving insulation. These also make homes much more energy-efficient.
- The cost ranges from $2.5 to $4 per sq. foot.
- BURs are durable and you can choose how many layers you want.
- The topmost layer provides sufficient UV protection and aids in the protection of the underlayers.
- These roofs are good for thermal regulation and household energy efficiency.
The downside to BURs is that they are very labor- and time-intensive, not to mention that the installation of each layer produces harmful odors.
Modified bitumen roofing or MBR
Laying multiple layers is not in trend anymore. Alternatively, we now use MBR. MBR is a single-layer or single-ply process. The bitumen used is polymer-modified asphalt that’s further reinforced with a material like fiberglass or polyester.
MBR is relatively easier to install and doing it yourself is also a possibility. Some types of MBR, however, require torches to melt material in order to form a seal. Peel-and-stick application also exists.
- The cost ranges from $4 to $8 per sq. foot. Contractors can do it cheaper ($3 to $7).
- MBR is easier to install and even comes with adhesive options.
- These roofs have high reflectivity and color options to choose from.
The downsides include the lack of durability (and therefore, the lifespan). An MBR can last you for 10-20 years. Blown debris, footfall, and natural agents can quickly degrade such roofs.
Single-ply membrane roofs or SPM roofs are a single layer of material that goes on top of a substrate (which you have to factor in if you go this route). These have a significantly longer lifespan and better performance. You can choose between PVC, EPDM, and TPO when it comes to SPM roofs.
PVC (Polyvinyl Chloride) single-ply membrane roofs
- PVC roofs cost $8 to $12 per sq. foot
- PVC roofs have remarkably low maintenance overhead and offer a considerably higher lifespan than most other roofs.
- The color options are many. You can even go with a patterned look!
- PVC roofs have high solar reflectivity.
On the downside, as PVC is essentially plastic, it can shrink over time and cause leaks or corner artifacts. Older PVC roofs can also shatter or puncture in the cold.
TPO (Thermoplastic Polyolefin) single-ply membrane roofs
- TPO roofs cost $5.5 to $6 per sq. foot.
- The material is very flexible and can be used to lay on top of irregular cuts and shapes of roofs or to go over and around obstructions.
- Affordable and highly reflective, these roofs are also recyclable.
- You can say goodbye to mold, algae, dirt, corrosion, and mildew growth with TPO roofs.
The downside of a TPO roof is that severe heat can cause cracks or busted seams. The lifespan is also short, 10-20 years.
EPDM (Ethylene Propylene Diene Monomer) single-ply membrane roofs
- EPDM roofs can cost anywhere from $6 to $13 per sq. foot.
- EPDM roofs are a common replacement for BUR roofs. You can choose between black or white and between reinforced or non-reinforced variations.
- These are highly UV resistant and reflective.
- Installation of an EPDM roof is easy.
- EPDM resists fires, impact, heat, strong winds, and thermal shock.
EPDM roofs can swell up when exposed to certain solvents and oils. Also, water can delaminate reinforced sheets of EPDM.
Have you chosen the perfect type of flat roof? If none of the above meet your requirements, then you might be interested in Spray Polyurethane Foam. SPF roofs are a liquid-applied solution for roofs that can seal every crack and corner. You can apply this spray on top of a material such as metal, roof decks, substrates, or even shingles.
Need help? Hire a contractor to advise on your exact situation and prepare a construction plan for your next home project.