Flat Roofing Materials and Why You Need Regular Maintenance
In a previous post, we covered the difference between a flat or low slope roof and a sloped roof. It touched on some of the common types of materials used for those applications, but today I wanted to write about some other types of flat roofing and talk about why they need so much maintenance.
There are four common types of systems. I will list them in order of increasing durability. Of course, increased durability means increased cost. They range from $4 per square foot to $20 per square foot. If you’ve recently bought a property, it means you did not have control over what material that was chosen.
Flat roofs generally need to be replaced every 15-20 years, so if it’s time to replace it, think about what an upgrade might do for you. Ultimately, your contractor should be able to recommend the best system for your building and should have a maintenance plan to get you the full life span you’ve paid for.
Remember, much of the value and durability in a flat roof comes from proper installation! When you hire a reputable company, you are putting money back in your pocket in prevented costs associated with a poorly installed roof.
Four Types of Flat Roofing Materials
- Asphalt roll roofing
Asphalt roll roofing has been used since the 1890s. It is generally made of one layer of asphalt saturated organic or fiberglass felt. It is applied over roof felt with nails and cold asphalt cement and then covered with a granular mineral surface. The seams are cemented together.
Asphalt roll only lasts about 10 years. Seams generally need repairs every 3-5 years and, they require regular inspection and maintenance by professionals or will usually fail rather quickly.
- Single-ply membrane roofing
Single-ply membrane roofing is the newest type of roofing material and often replaces a multiple-ply roof. There are several brands and types of products on the market: modified bitumen, rubberized asphalt, EPDM and PVC sheets. They can be self-adhering, applied with hot asphalt or heated on the underside with a propane torch or other device.
This type of roof should only be installed by roofers who are authorized by the manufacturer because of the level of skill and experience necessary. These products are generally warranted for 15-20 years with regular inspection and maintenance.
- Multiple-ply roofing is also called built-up roofing (BUR)
Multiple-ply roofing is made up of overlapping rolls of coated felts or mats that are interspersed with layers of bitumen and then may or may not have a granular or ballast type surface applied to protect the underlying materials.
BUR systems can last from 10 to 30 years. However, because they are multi-layerd and may be covered, inspection and maintenance can be more difficult.
- Flat seamed metal roofing
Flat seamed metal roofing has also been in use since the 19th century. It is made up of smaller pieces of metal soldered flush at the joints and can last many decades with the right material and maintenance.
The weather also plays a key role in how long this type of system lasts. Galvanized iron, for instance, takes regular painting in order to avoid corrosion and split seams have to be re-soldered. Acid rain can make small pits and pinholes in metal surfaces like copper, but copper, lead-coated copper and coated stainless steel are good for roofs that need to last a long time and are more inaccessible – it also happens to be the most expensive.
Why Does Your Flat Roof Need Regular Maintenance?
A flat roof may appear simpler, but its main problem, as with any roof, is water. A badly damaged sloped roof will still shed the majority of water because of the pitch; however, even a small hole in a flat roof will leak into the building below, especially if blocked drains are causing puddles to form on your roof.
In addition, flat roofs are more susceptible to debris than pitched roofs because they are flat. If you own a property with trees, you need to plan for inspection and maintenance two to three times a year. Low areas may need to be built up with rigid insulation and a new surface if they are not draining well.
An inspector will look for “blisters” which are sections of roofing that feel mushy. These are layers of roofing that have allowed water in between them. They will need to be cut out and replaced. He or she will also look at the overall surface of the roof to see if it’s cracked. If so, it may need recoating. The inspector may also recommend reflective aluminum paint to minimize the damage to the materials by the sun.
Too many property owners neglect their flat roofs by failing to inspect or maintain them as often as they need. It is better to be proactive than reactive when it comes to maintenance.
Contact us today to make an affordable inspection appointment. We can recommend a maintenance plan or if it’s time to replace it, we can put a maintenance plan in place for the future. If you’re experiencing leaks, now is the time to call.