Mechanically Attached Vs Fully Adhered Roofing Systems

by Rhoden RoofingSep 18, 2018

Single-ply membrane roofs (TPO, PVC, and EPDM) are typically fastened to commercial buildings in one of two ways: mechanically attached or fully adhered (there are others but these are the most popular). Virtually all roofs sit on top of a layer of insulation or cover board that rests between the single-ply membrane roof and the structural roof deck.

Here is a quick comparison:

*CATEGORY*	*MECHANICALLY ATTACHED*	*FULLY ADHERED*	*WINNER*
WIND UPLIFT:	Great wind uplift resistance (depending on attachment method)	Superior wind uplift resistance	FA
HAIL RESISTANCE:	Good resistance (depending on substrate)	Superior resistance (depending on substrate)	FA
INSTALLATION COST:	Less expensive	More expensive	MA
INSTALLATION TIME:	Quicker	Slower	MA
INSTALLATION TEMPERATURE:	Any temperature	Warmer temperature	MA
ENERGY EFFICIENCY:	Lower due to air intrusion and fluttering of the membrane	Higher – acts as an air barrier	FA
DURABILITY:	Medium	High	FA

So which is best?

That all depends on your budget, type of building, and your performance expectations.
A Fully Adhered system will out perform a Mechanically Attached system every time.
When it’s time for a new roof, always consult with an experienced and trusted roofing contractor to determine the best system for your building.

Pro Tip: Mechanically Attached and Fully Adhered both require proactive preventative maintenance programs to prevent hazards from becoming leaks and to prolong the life of the membrane. Manufacturer’s require a maintenance program to keep the warranty in good standing. Rhoden Roofing offers a preventative maintenance program called RoofCare. RoofCare is designed to save building owners money, increase the lifespan of the membrane, and reduce headaches that come from unexpected & preventable leaks.