Understanding and repairing membrane shrinkage to extend the life of your commercial roof.
Membrane shrinkage is the gradual contraction of roof membrane material over time. This natural process occurs as the membrane loses volatile oils and compounds through UV exposure and heat cycling. As the membrane shrinks, it pulls away from edges, walls, and penetrations—creating gaps for water infiltration.
This is especially common with EPDM (rubber) roofs, which can shrink 1-5% over their lifespan. While this might sound minor, on a 10,000 square foot roof, even 1% shrinkage can mean several feet of lost membrane—pulling away from critical seams and edges.
Shrinkage manifests in different ways—each requiring specific repair approaches
Membrane pulls away from the roof edge or perimeter flashing. Creates a gap where water easily penetrates. Often seen as a visible gap between membrane and edge metal.
Heat-welded or adhered seams experience stress as membrane contracts. Seams can separate, lift, or tear at stress points. Most common at field seams and transitions.
Membrane develops wrinkles from contraction stress. These wrinkles can trap water, debris, and become walking hazards. Water can infiltrate through wrinkled areas.
Membrane shrinks away from pipe boots, HVAC curbs, and other penetrations. Creates gaps at these critical transition points where water readily enters.
We measure and document membrane shrinkage, identify stress points, and assess the overall condition of the membrane system.
We re-secure the membrane at edges and perimeters, installing new edge metal or re-anchoring the existing membrane to prevent further pullaway.
We repair separated or stressed seams using proper welding techniques. For severely stressed areas, we may install overlay patches for reinforcement.
We apply reflective elastomeric coatings to protect the membrane from UV damage and slow future shrinkage. This also improves energy efficiency.
Don't wait for shrinkage to cause serious water damage. Our experts will assess your membrane and provide lasting solutions.