who knows about spray foam?

[keakar]

is all spray foam the same or is there any differences other then open or closed cell versions?

I get the sales pitches saying "mine is best, don't trust what others use" and something like "some brands don't insulate or hold up as well as others" but its hard to know if its salesman BS or not.


does anyone know enough about this stuff to say one way or the other if its all the same or not?

[rustyb]

What are you using it for?

[keakar]

wall and under floors.

getting open cell for walls and closed cell under floors

the ceilings will just be regular insulation

[rustyb]

Closed cell is better where moisture is a problem

[worm]

My house and shop has spray foam. Metal shed has closed cell, house has open cell. The closed cell (Shed) is about 1/2 inch thick and helps support the metal building.
The open cell (house) is 3 1/2 inch thick to fill all gaps before sheet rock was installed.

Both are great insulation but do some research on moisture and spray foam. I recommend you call several qualified HVAC companies and discuss what type of Heat/AC system you will need to ensure no moisture problems.

Sorry cant help on what spray foam is best, but I will never own a house without spray foam.

[biggun]

Worm

Did U spray that Ur self??

[worm]

No I had a contractor spray the foam.

[FF_T_Warren]

What's better spray foam or blown insulation? What's the cost difference?

[keakar]

Originally Posted by FF_T_Warren

What's better spray foam or blown insulation? What's the cost difference?

well from working in attics for 30 years I can tell you I hate blown insulation and think its crap.

my reasons are, it never stays put, and it moves with little effort like a pile of leaves in that its prone to blow around, so any drafts from attic vent areas can and do often leave areas within a foot or two of that area, devoid of insulation after a few months by slowly moving the insulation away from the drafty area.

second, as you walk move or work in the attic it gets shuffled around and matted down and is never the same again so if you have anyone working in your attic (no matter how much you trust them) you better go up there behind them and "rake the leaves" as it were to evenly and uniformly spread it out again.

lastly is its prone to leave too much dead air space between the tuffs so if its 6" deep its no better then a 3" solid bat because of all that air space mixed in.

now all that being said, its better then nothing, and its often the only reasonable alternative to insulate areas that are hard to get to, so it has its uses, but I wouldn't put it in a new house just to save money because in the long run its no where near as good as regular bat insulation.

spray foam is the best choice for insulation but you always want to use a bat for the ceilings so its not completely foam. if its all foam you need special considerations to handle the stale inside air and trapped moisture so the a/c system must draw in outside air to replace the inside air and then this diminishes the a/c system efficiency and raises its initial as well as running costs all because when you have too much foam everywhere, you get moisture issues and stale air factors. the main problem with foam is its a great insulator but its also a moisture barrier that doesn't allow the house to breathe so having it in the walls is good but don't "seal the box" by doing the ceilings with it, that's too much "sealed" air and moisture in the house. its like what happens to an ice chest or unplugged refrigerator you leaved close for a while, the air gets funky as hell and mold starts growing in it.

this is why I am foaming my walls and floors but using regular bat for the ceilings to avoid moisture and stale air issues.

hope that helps

[cajunforeman]

I did a ton of research on foam when I was building my house. I couldn't justify the cost vs return by putting in foam. Your a/c will cost more and of course to spray it will cost more. It was going to take at least 20 years to get my money back even including the savings i estimated on my electricity bill being reduced. I also worried about the moisture concerns mentioned above. We don't exactly live in a dry area. I went with blown fiberglass. I figured it was the best bang for your buck. Hope this helps

[keakar]

Originally Posted by cajunforeman

I did a ton of research on foam when I was building my house. I couldn't justify the cost vs return by putting in foam. Your a/c will cost more and of course to spray it will cost more. It was going to take at least 20 years to get my money back even including the savings i estimated on my electricity bill being reduced. I also worried about the moisture concerns mentioned above. We don't exactly live in a dry area. I went with blown fiberglass. I figured it was the best bang for your buck. Hope this helps

it is a tough choice and one im still on the fence about.

for my 900 sq ft house it would cost an average of $1000-$1200 for spray foam in just the walls vs I could buy the regular bat r-13 insulation for only $280 plus tax and install it myself. I just keep hearing people saying how great foam is and that you shouldn't consider using anything else but isn't it always like that with the latest greatest new stuff? plus its like 4 times the price of regular insulation and as you say, how long will it take to pay for itself?

i know i will need spray foam in the breaker panel cavity where there is no room for anything other then spray foam with all the wires and small gaps in there, since only the foam can fill and form itself around all of that, but the rest i am still pondering and until your post, i had no gauge on how much foam would save to offset the costs of doing it. i thought the return on investment was more in the range of only 8-10 years.

[Gerald]

second, as you walk move or work in the attic it gets shuffled around and matted down and is never the same again so if you have anyone working in your attic (no matter how much you trust them) you better go up there behind them and "rake the leaves" as it were to evenly and uniformly spread it out again.

This is very true.

Something I wish I had in my attic is an elevated walkway to get back to where my A/C unit and hot water heater are located. Install the walkway support boards before the insulation is blown in. The top boards can be installed after the insulation is put in.

Then also raise up the A/C and hot water heater about a foot. This will keep the insulation "mostly" intact and doing it's job to insulate your house.

[scd]

I have it blown in the walls of my house, I had what the contractor called a flash coat on top of the ceiling in attic then blown fiberglass on top of that. All open cell. So you could say the living area is encapsulated. At the time the air conditioner manufacturer was offering a special on buying a complete (AC/filter/fresh air) system. At the time (5 years back), the technique we used in the attic was un-tested. The attic is vented and not sealed like as if I would have sprayed it on the bottom of the roof and sealed the eves. Additionally I made sure that all windows, base plates etc were sealed as best as practical. Moisture can be an issue in my house. I have one A/C unit for a 3100 sq ft house and I have to force it to run to get the moisture out. It is one of the units that monitors moisture and has settings to help manage it and I have to set it at its maximum to keep moisture below 60% during the spring and fall (mild temps). The house is like a cooler as someone else has mentioned. Whoever said the blown stuff in the attic moves is spot on. My electricity bill is low, very low considering. My brother in law actually had his roof rafters blown and sealed eaves with foam (encapsulated his attic), the guys sealed the walls around penetrations with foam then blew some sort of fiberglass or wool in the walls. He has a similar size house and just slightly higher electricity bills yet not the moisture issues. The guys who installed the AC were the same guys who suggested and installed the insulation. He paid less than I did, his AC unit and anything else he has in the attic is semi conditioned which lowered the cost ac ducts etc as he installed the minimum insulation on those as the attic area is semi conditioned. There was about a three year difference in the building of our houses and seems like he got a better system. He paid less, his ac unit, water heater, whatever is in the attic will see less heat damage, he doesn't have moisture issues and his electricity bills are about the same. Bottom line is that foam is an awesome product, yet application needs to be thought out.

[Gerald]

SCD.....

Something you might want to try is a small Dehumidifier. A neighbor was telling me that they had a problem with the master bedroom not being comfortable on the days that the A/C unit did not run much.

To try to make things better they bought a small dehumidifier from Amazon for about $ 45 and really liked the improved comfort.

I also bought one and like how much water it takes out of the air in the house. It has a 16 oz container that fills up in 4 to 7 days. It is fairly quite [ours is in the den about 5 -8 feet from where we watch TV] and is small [6"W X 8.5"H X 5"D].

Here is a link:

Amazon.com - Eva-dry Electric Petite Dehumidifier Edv-1100, White -

Amazon.com - Eva-dry Electric Petite Dehumidifier Edv-1100, White -
Amazon.com - Eva-dry Electric Petite Dehumidifier Edv-1100, White -

[Samarai]

our spray foam for our 7000 sq ft house was right around 25,000. for us to use bat insulation, it was around 18-19,000. we have been living in the house for a couple of months now and the bill in Jun, July, and august was around 200. The house is kept at 72 all the time. Of course we self contracted our build so prices may be a little higher if u had a contractor build. Walls were 2x6. I could walk in the attic in the middle of summer and not break a sweat. Naturally we have led bulbs all over the house so that adds to some savings.