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Does spray foam insulation work

I have been looking at using spray foam insulation in my upcoming home build. Everytime I mention it my builder get this funny looks and mentions how much extra it costs. He says that his HVAC guys don't reccomend it and are not willing to resize/downsize tonnage based on spray-foam.

Does open or closed cell spray foam insulation work to reduce noise, air infiltration, and improve efficiency? Will I be able to reduce the necessary tonnage of my HVAC unit?

Any help in clearing the confusion is much appreciated.

Re: Does spray foam insulation work

I personally don't have any experience with it but if I was having a builder build a new house, I would use it. It has the benefits you mention. Ohter insulation methods require scrupulous work to plug all leaks, which was done poorly in my house. It is difficult to plug the leaks once the house is built. Perhaps you can search for a HVAC person yourself and recommend him to your builder.

Re: Does spray foam insulation work

I am current in the finishing stages of a big rehabilitation project of my small house. Last winter I had the spray foam put into my house. The stuff is incredible. It basically eliminates all drafts. I'm sure everyone here has had or has been in a house that if you put your hand near a light switch you can just feel the cold air pouring in. That does not happen with spray foam insulation. Some of the benefits to the builder would be it does not require a vapor barrier. If it is sprayed directly to the under side of the roof no ventilation is needed (At least where I am, check with the building code in your area).

There are a couple of downfalls too. Since the house is so tight you need to bring fresh air into the house. If your HVAC system does this you are in good shape. If not you should get a Heat Recovery Ventilator (HRV) which will bring in fresh air when all the windows and doors are closed. Also you need to make sure that all of your wires are run where you want them because once the foam is in the walls it is very difficult if not impossible to pull new wires.

As far as How I like it. I love it. Before I even had heat in the house I would go there to work. I would turn on the lights (Probably 10 100W work lights) The temperature went up in the house by about 4 or 5 degrees with just the lights on. Once I had the heat on I kept it at about 55 to 60 degrees and most of the time had to wear a t-shirt to work in. Yes it is a bigger investment but I think it will pay off in a fairly short time.

As far as the open and closed cell, I believe the closed cell is for walls that are already covered. It doesn't expand as rapidly so it won't blow out the walls. Open cell is fast expanding and used in open walls. I think I have that right or its the opposite way.

As far as your builder and HVAC contractor. They may have never used it or done a house with it. The HVAC contractor should always take into account the amount and type of insulation when figuring the heating and cooling load. Maybe you need a different contractor with more experience in spray foam insulation. I hope this helps you out.

Re: Does spray foam insulation work

I would have to agree with sabo4545 ... spray foam is far more superior than conventional bat insulation. If applied correctly there will be no air infiltration and eliminates any vapor barrier required for bat insulation. There is an up charge of at least 30% for this type over conventional bat insulation but that will have some payback considering it does provide superior insulating.

Likely the general contractor is reluctant to new techniques but there should be no issues with the HVAC contractor.

Re: Does spray foam insulation work

YES! it does work. The upcharge for spray foam insulation will pay you back in lower utility bills. Spray Foam Insulation is the BEST Insulation you can get, and you have to remember that you only get ONE shot at insulation. You can replace heaters, AC units, boilers, etc alot easier that you can insulation.

Re: Does spray foam insulation work

I believe if I got that kind of answer from a builder I would be looking for another builder and HVAC contractor.

Re: Does spray foam insulation work

I have it in my home.
The mechanical guys asked what type of insulation and windows I was going to install when they figured the units I would need. I was able to be one size lower due to the insulation and windows. I also had a Honeywell "perfect window" installed for fresh air. I am happy with everything so far after 6 years.

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