Closed-cell foam vs. open-cell foam
I am sure his topic has been discussed in detail, but I just received FHB magazine today and read article by Martin Holladay. a few years back I did a remodel and expansion of our house. I did remove much of the drywall on walls, but not 100%. The company I hired to do CLOSED cell foam was a bit new and maybe I did get a price break. But when I compared to Open Cell foam it was about 75%. This was with Icynene open cell. I have been happy with the closed cell. Also I thought closed cell has the advantage of making a tigher home vs the open cell. The one area I knew open cell was better is sound deadening which is always a plus.
We do plan on building a new home in the next few years and have been looking at much of the FHB and will use this website to review recommendations. It seems to be a bit difficult to get others to understand and / or use the new recommended techniques. Even with the closed cell 5 years ago, when the inspectors came, he had no idea if it was ok or not. He said he needed data on the product etc. After his 3rd time back, he said you are the homeowner, I am not sure what it is exactly but if you are ok with it, I will approve. Recently I had some hail damage on roof, not sure I want to replace myself and insurance covered so I had a few estimates. A few companies would not take the job because of no venting on the roof, this was event by one of the big box stores.
I will have to read more about the different products on this website, but it surprised me a bit in the article where it stated closed cell costs more, where it was 75% of what the open cell people wanted. I have been happy with the closed cell. I did have one roof leak and it was a bit more difficult tracking it down. It ended up being where I added additional roof support a nail curved up and penetrated outside. A bit of sealant fixed that luckily.
It sounds like he was recommending open cell over closed cell in all aspects. If so, I guess I need to find out before I build new home 🙂
Before I put drywall on, I used an infrared thermometer on the walls. One day when it was about 15 degrees F outside, I pointed it on a wall with various thickness of closed cell. (yes, I agree closed cell is a pain to scrape, and to get even ) At about 1″ wall temp was 64, at 2″ about 66, and 3.5″ thick was about 68 while inside temp was 68-70. So to pay the 2x price to go from 2″ to 3.5, likely not worth it. Seemed like average of 2″ was fine. It is definitely better than the old fiberglass batts that it replaced. Home is much quieter and dont feel any drafts.
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