Costly Flat Roof Leaks – 10 steps to Find and Repair Leaks DIY

Four different Roof Systems each with their own leakage problems from seams

EPDM Rubber Membrane –

You can tell it by the look and feel of it. It is smooth and looks like the rubber of an inner tube of a tire. This is the most common roofing material used by most roofing contractors.

Watch this video if you have an EPDM rubber roof

This video will show you how you can save any EPDM roof from failing prematurely, especially at the seams. All EPDM rubber roofs will have seam failures due to the adhesives breaking up from excessive heat.

This video will show you how to extend the life of your roof.

TPO Vinyl Membrane –

This is normally white and has a plastic vinyl feel to it. This type of membrane has gained popularity and is preferred by roofing contractors.

Modified Bitumen Torch Down Rubber Membrane –

This type of rubber membrane comes only three feet wide, So if you see seams every three feet wide you know its some kind of a Modified Bitumen rubber. These membranes are either painted with a Silver paint or have Ceramic granules embedded on the surface.

Metal Roofs –

The overlapping panels on a metal roof create a seam that is sealed with a foam gasket. This gasket will deteriorate over the years and the neoprene washers with the fasteners will also not keep these two panels tight together. The constant moist generated by condensation will cause these seam areas to rust and allow water to leak in.

The video below shows you how to repair Flat Roof leaking on a metal roof seam with Turbo Poly Seal

Conclusion on Roof Seam Leaks:

Torch Down and TPO roofing membranes are heat-welded seams and therefore are less prone to separate and cause leaks.

EPDM Rubber, on the other hand, uses contact cement or adhesives to bond the seams. Because of the extreme heat that is generated on a black EPDM Rubber during summer, the glues start to fail and causing leaks.

How to look for a leak caused by roof seams

• On an EPDM Rubber roof, go to the overlapping seams, with your fingers, see if you can pull up on the EPDM material. When the adhesives fail that is bonding the seams together, then you will easily pull them apart.
• On a TPO roof: use a screwdriver and see if you can drive it in between the seams. If a weld has failed, you will find that a flat screwdriver will easily get into a seam.

• On a Torch Down Rubber Roof: To check the seams if they are causing the leaks, use a round nose trowel and try to pry it in between the seams. You should not be able to move the trowel in the seams more than 1/8 of an inch.

• Metal Roof Seam: Check the overlapping seams of the roof panels and make sure they are tight together. When the seams start heaving up due to the wearing of the neoprene washers and fasteners, it will have leaks.