My framing contractor recommends use of foam spray insulation instead of fiberglass insulation. As such, he does not plan to install a ridge vent, whirly birds, soffit vents, or gable vents.
I am building a 2,500 sf house installed on wooden piers 2 ft off the groung. It will have pine siding, metal roof, and double paned windows. Location is 90 miles north of Houston, Texas.
He claims that the attic does not need to be vented as is typically done wirh traditional fiberglass insulation. He says that the A/C heating system that will be installed in the attic will need a fresh air supply. The hot water heater will be installed in a closet on the main floor. Also, my framing contractor claims that foam insulation is more expensive but the increased costs will be recouped in 4 to 5 years as a result of lower utility bills.
Questions: Does the attic needed to be ventialed if foam spray insulation is used? If so, what type of venting? Also, do you forsee major issues with spraying over electrical wiring in walls? Example – need to pull additional cable in future due to a faulty cable. Also, I’ve read a few horror stories about fumes emitted from foam spray insulation that smelled “fishy”, made occupants ill, and cost big money to remove, etc. How do I as a consumer protect myself from this type of situation? Thanks in advance for your help.
Tom: Well, first off, you can spray the foam on electrical wires and things just to get that out of the way, and foam is being pushed like crazy today, but I have a real concern about the way the question’s written and I know exactly what’s going on: There’s nobody leading the job. She’s talking to a framing contractor who’s making all the decision for her and that’s not the way a project’s supposed to go. Hopefully the plans were drawn, everything is in the plans that are supposed to be there. Just picking and choosing as you go is a real poor way to build a project and I think she’s going to be in trouble if she listens to a framing contractor about all the details. I would say “no” to the foam, myself. I would definitely use fiberglass. You have to ventilate a attic. If you do foam up an attic, no, you can’t ventilate it because it’s impossible. He’s right about that, but that doesn’t mean it’s the right way to go. Okay?
Charlie: Fair enough.
Tom: Get someone to lead the project properly.