Roof coatings: acrylic vs silicone
I am trying to understand the Pro/Con of Acrylic vs Silicone coatings.
Location: Hawaii (warm all year, very high UV, no heating)
Home: Single story 1960’s shallow pitch (2:12) with very low slope enclosed patio (but water does run off — not completely flat – no ponding). No air conditioning (yet).
Roof: ¾” Plywood + 2-ply Bitumen
PROBLEM: Home is HOT due to no insulation over high open beam ceilings
DESIRED EFFECT FROM ROOF COATING:
Reflectivity to cool home (hoping for 10 degrees)
I hear rumblings about the need to recoat after some period of time
I have also heard aobut dirt and dust sticking/attracted to some coatings more than others which leads to algae growth/accumulation of debris that reduces reflectivity.
Commonly used products I have seen –
Lots of GACO silicone
Some APOC silicone
Any favorite products out there, and why?
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