People live by exaggeration. This extends into some modes of speech as well, from little sayings like “I’m so hungry I could eat a horse” to slight inaccuracies like calling a flat roof “flat.”

A flat roof is really a low-slope roof (or should be), with a slight slope that enables any water collected to be directed into a built-in gutter system. The problem with flat roofing is that sometimes the water does not roll out the scuppers and down the hopper, resulting in ponding and water damage. Becoming familiar with the typical layers of a low-slope roof can make your flat roofing repair and maintenance easier and less expensive.

Core Sample

If we could drill down through the layers of your low-slope or flat roofing, we would find a far more complex assembly than most people realize. Take a typical single-ply roof as an example. From the membrane exposed to the weather down through your building you will find:

  • Single-ply layer
  • Insulation
  • Vapor barrier
  • (Usually) another layer of insulation
  • Steel roof deck

Surrounding the edge of any low-slope roof is flashing, which climbs the parapet or runs over the edge of the roof to cap the walls. Flashing prevents water infiltration behind or beneath the roofing surface.

Caution Signs

Once you know the general anatomy of a flat roof, you can instantly see where trouble spots should send up caution signs for you. The single ply membrane is tough, but still requires careful maintenance. Very little beneath it will protect your building from water damage, so treat the single ply membrane with respect:

  • Avoid heavy foot traffic
  • Get frequent roof inspections to find and repair small tears or seam separations
  • Prevent sharp objects from contacting the surface

Similarly, with BUR and modified bitumen, careful inspection can reveal areas where layers separate, ballast fails or seams open.

All flat roofing needs inspection and repair of flashing, which can become dislodged, get punctured, or undergo galvanic corrosion from contact with dissimilar metals.

Since we know flat roofs are not really flat, we expect water to roll off and drain correctly. Unfortunately, improperly constructed low-slope roofs (or older roofs) can develop low spots that allow ponding water to collect. Frequent inspection and maintenance can limit the damage caused by ponding or plugged scuppers and drains.

To best protect your flat roofing, contact BELDON® Roofing Company today to schedule a professional inspection of your low-slope roof’s anatomy. We will provide a thorough and thoughtful report, and that is no exaggeration. It is a promise.

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