When it comes to weatherproofing your RV roof, the Flex Seal liquid roof is one of those we’re proud to recommend because it can be applied in all temperatures. It can also protect your camper roof from even the harshest weathers, including rain, snow and wind. With it, you can keep your roof protected from changing temperatures, eventually prolonging its lifespan.
If you’re not familiar, spray foam is a type of insulation that expands after you spray. The foam expands and seals, avoiding any type of unnecessary moisture (which can create mold) or encouraging pests to eat through your walls. It protects the lining of your house, and even can protect the heating and cooling of your house during those unbearably cold or hot days.
a) Make sure that your house has been well heated prior to installation because the foam expands at different rates as it hits surfaces with different temperatures. If it is cold outside the sheathing may be much colder than the studs consequently the foam may expand more from the sides of the wall cavity creating air pockets in the wall cavity. This can be minimized by an experienced installer. https://www.youtube.com/watch?v=ggLAUsiuI_o
However, coating asphalt shingles and built-up composition roofs requires more caution. The National Roofing Contractors Association’s (NRCA) director of technical services has stated "The roofing industry is aware of a number of issues that could have negative consequences for field application of coatings over asphalt shingle roof systems. Anyone considering this type of application should be aware of the concerns so they can weigh them against the benefits claimed in coating product promotional materials."
We had issues with getting this foam to turn green in summertime in the South. We needed up spending an additional $300 on being able to spray this foam: 110 window a/c for shop & a $60 tarp to drape over the top, to keep the temps down. The areas where we had trouble-shooted were sticky & even after we wiped it down, the new green foam wouldn't stick. My husband had to apply Liquid Nails to it. For over $800, I expected alot more, plus the sellers customer service skills were in need of improvement.
DID YOU KNOW? Spray FOam insulation out-performs conventional insulation materials because they (conventional insulation materials) trap still-dry air and if that air moves or becomes wet, the thermal resistance can drop by 50%. Spray Foam protects against air infiltration, which can increase energy costs in buildings by 10 to 40%. Eliminate these drafts and live in a more energy-efficient, comfortable and healthier building by choosing spray foam insulation.
Spray Foam Contractors
I don't know if it's common or uncommon, but installing a layer of rigid foam above your roof sheathing in order to interrupt thermal bridging is always a good idea, and is preferable in all respects to a roof assembly without any rigid foam above the sheathing. If you decide to install rigid foam above the roof sheathing, you shouldn't use closed-cell spray foam under the sheathing; either use open-cell spray foam (which is vapor-permeable) or a fluffy insulation like cellulose, mineral wool, or fiberglass (any of which will allow the roof sheathing to dry to the interior).
If you haven’t considered spray foam insulation, now may be the time to start looking into it. As you know, having proper insulation will help reduce your heat and air conditioning bills. In specific, spray foam insulation can be particularly helpful during renovations. It can provide a barrier between outside walls, and even a sound barrier for the inside.
Allison--would be very interested in your take on the GHG issues of foams, which have received lots of smart commentary recently. To highlight a few: architect Jesse Thompson's comments on Tom's Good vs Bad post on Energy Circle, the very thorough piece by Alex Wilson on Green Building Advisor and Michael Anschel's cautionary diatribe on Remodeling. http://youtube.com/v/ggLAUsiuI_o
If what you are looking for is a fiberglass roof coating for your recreational vehicle, then the Dicor RPFRC1, which is available in a 1-gallon container is an ideal option. It makes use of a hundred percent acrylic fiberglass resins formula, which is effective in providing a more flexible coating, which tends to contract and expand with each roof movement.