Mechanically Attached Vs Fully Adhered Roofing Systems

by Sep 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.

 

Fully Adhered Illustration

Mechanically Attached Illustration

Latest Posts