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How Often Should The Flat Roof Be Replaced?

A flat roof is made up of several layers of waterproof materials that hang over a structural deck above the building. The vapor barrier in between the layers prevents moisture buildup, which could cause serious damage to the roof. Flat roofs can last for a very long time with correct installation and proper maintenance. If you own a commercial or residential building with a flat roof, it is important to learn a few maintenance tips to ensure it lasts longer than expected. This article discusses how often you should replace a flat roof on a building.

The Average Lifespan of Flat Roofs

The different types of roofing materials used during construction determine how long your flat roof will last. Some of the common types of residential flat roofs include PVC, TPO, Built-up roof, and Torch down.

Flat roof installation. builders workers heating, melting and applying bitumen roofing felt by flame torch at construction site

A built-up roof can last between 15 and 20 years depending on how well it is maintained. It is built with hot tar and at least three or more layers of waterproof material that are ballasted with a smooth layer of river stone.

PVC flat roofs are reinforced with fiberglass or polyester to create a durable roofing material. Since they are highly resistant to both fire and UV rays, you can expect these roofs to last up to 30 years. The thermoplastic polyolefin (TPO) is a versatile flat roofing material that offers similar qualities to PVC and can last between 15 to 20 years. Modified bitumen or torch downs have a shorter lifespan than PVC and TPO. They are single-ply rolled roofs that have been treated with a mineral-based wear surface.

When Do I Know If I Need To Replace My Flat Roof?

  • Moisture and Leaks

Any water leakages on flat roofs will not have anywhere to go but down. Moisture that seeps through the roof membranes increases the potential of fungus and mold growth. The best way to deal with leakages in flat roofs is to have them inspected by a professional and maintained regularly. A reputable roofing company can advise on the best course of action if problems are caught early.

  • Bubbling and Blistering

Blistering and bubbling are defects that arise from adhesion failure. Visible bubbles on a flat roof are filled with either water or air. This is could be caused by bad insulation, poor workmanship, or insufficient ventilation. Blisters and bubbles on flat roofs can be too large to be fixed when left untreated. Once they pop and leave holes in your roofing, it can make your building vulnerable to interior damage.

  • Water Pooling

Pooling water is probably one of the biggest issues you can experience on flat roofs. The roof may shift slightly over time, which means it will not be as level as it was when it was initially installed. This causes water to pool in dips and divots. When left unchecked, these water pools can shorten your roof’s lifespan by causing more damage to the interior layered surfaces of your flat roof.

  • Cracks, Splits, and Tears

Any untrained eye can spot cracks, splits, and tears on a flat roof. However, when you do not take action, the chipboard or plyboard will absorb water causing more damage over time. Not only will the roof be unsafe to walk on but it could also prevent it from functioning at its best. If the problem is not extensive, you can choose to repair it. However, if the cracks and splits were all over the roof surface, it would be best to schedule a replacement.

Deciding Between Total Replacement and Sectional Roof Repair

The decision on whether to repair a section of the roof or do a total replacement could vary depending on the type and extent of the problem. Performing repairs on minor issues can help deal with the problem before it becomes worse. However, if the flat roof is damaged extensively, professional roof contractors will suggest roof replacement as the best course of action. There are times when the cost of repairing may turn into a never-ending exercise. Not only will a roof replacement be a cost-effective solution, but also saves you the time and restlessness of going back and forth on endless repairs.

A flat roof should only be replaced when the cost of repairs exceeds the total cost of replacement.  The best way to ensure that your flat roof lasts for a long time is to have it installed by a professional and maintained regularly to keep it in good condition. Dealing with small problems before they become worse not only helps you save money but also ensures your flat roof lasts longer than expected.