For large jobs, professionals such as Dr. Energy Saver use two-part foam, which comes in larger containers. With 2-part spray foam, it's necessary to mix separate resin and catalyst compounds at the application nozzle. Combining these ingredients starts a chemical reaction that creates expanding foam. Contractors use small 2-part foam "kits" to air-seal an attic or to seal and insulate ductwork. To insulate an entire attic or wood-framed wall with spray foam, the resin and catalyst compounds are pumped to the application nozzle from 50-gallon drums in a specially equipped truck.
To avoid the expense re-roofing a house that is simply suffering from nail fatigue, and to obtain optimum insulation, an 85mm layer of polyurethane foam can be sprayed onto the underside of the slates or tiles of a pitched roof. This stabilises and weatherproofs the roof by fixing the nails, battens and roofing felt. As the foam is a superior insulant, coupled with just 100mm of insulation at joist level, your roof will also meet the stringent thermal performance standards required for a new home. A typical roof can be insulated using the polyurethane treatment for around half the cost of re-roofing.
High-pressure systems can be used to spray all three types of spray polyurethane foam. Of the three types of spray foam used in building insulation and weatherization, the high-pressure, two-component spray foam is most likely to be used on larger projects such as a new building construction or renovations. SPF applied with a high-pressure system tends to adhere tightly to the entire structure which helps avoid sagging or detaching from its position. It can also provide a seal against air and insects.
Check with the coating manufacturer who may be able to suggest applicators who have used their products and have familiarity with the application. Another option would be to interview contractors and ask specific questions about their proven ability to install roof coatings. Contractors affiliated with the National Roofing Contractors Association (NRCA) or local roofing contractor trade associations typically are more knowledgeable. Consult those groups’ websites for contractors.
I have never used foam insulation before and this was easy for me to use right out of the box. I had a 4'x8"x8" cavity in my basement that houses a waterline. When the previous homeowner installed this they put no insulation in at all and being that it's an exterior wall in the basement and I live in the Midwest that thing was pushing so much cold air in it was incredibly uncomfortable. Out of the box and job completed in about 5 minutes. Stopped all drafts and created a nice 2" barrier on the wall in which I will install some extra bat insulation over it. 4 stars because the spray isn't very good passed 6-8" from the surface. Make sure you can reach the surface you want to coat. Great for small jobs!
Spray foam insulation is typically priced by volume, meaning your cost will depend on how much material you need to use to insulate your space, although other factors may influence price as well. In most cases, the cost of spray foam insulation is more than worth it, as it's a once and done upgrade that will not only provide energy savings in your home, but also improve your home's overall comfort. https://m.youtube.com/watch?v=ggLAUsiuI_o
Thank you, Allison. We have a split system unit (actually 5) with the heat being propane. The foam guy said that it needed ventilation, so completely sealing the attic wouldn't be a good idea. It sounds like you are saying that the systems need to be vented out of the attic or replaced with some type of closed system. But I shouldn't bother spraying if the plan is to leave the soffet vents open. Is that correct?
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).
Spray foam insulation, when properly installed is both an air barrier and when closed cell foam is used at the proper depth a vapor barrier! Before hiring any contractor you should establish the brand of foam being used and verify that with the named manufacture. Please ask for ESR reports and MSDS sheets on any foam being installed in your home. A couple areas where you might consider spray foam insulation include: http://www.youtube.com/v/ggLAUsiuI_o&feature=share
OK, Peter, I finally went back and read Alex Wilson's article on what he perceives as a serious problem. I haven't seen the full report, but based on the summary he wrote on the Green Building Advisor website, I question the science. It seems to me that he's chosen the wrong metric and he's basing his conclusion on too many assumptions because he doesn't have enough data. You can see my comments at the end of his article.
Fill and seal expanding foam sealant is urethane Fill and seal expanding foam sealant is urethane foam designed to fill large areas quickly and permanently. Uses include filling holes cracks or gaps that require a complete airtight and waterproof seal but are too large to be filled with ordinary caulk. The foam expands approximately 3 times its original ... More + Product Details Close