Living with foam insulation …. so far
Jeff_Clarke
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Nice!
And that was with our ERV running, which does bring in somewhat cooler outside air, despite some tempering.
Jeff
Glad the foam's suiting you. Got a review on the ERV? Recommended or not? With what caveats?
So far I'm pleased ... in cooler weather the air takes a few minutes to warm up - waiting for COLD weather to see what that's like.
Will let you know - one of the few in NJ so far, believe it or not, according to our supplier.
Jeff
Part of my garage apartment is the concrete pad otherwise 75% of it is raised frame flooring. Everything but the pad in the laundry room is sprayed foam (icynene), the floors, crawlspace, walls, vaulted ceiling, and gable ends... like a cocoon. The pad is always cool to the touch. I come in the house on a 90 degree day and it is cool in the house because the of that cool pad. Then after a while my body heat and the various electronics raise the temp so I do turn on the A/C at that point.
Yep the difference between indoor and outdoor temps is pretty stark evidence of how well these foam systems work. I am sure I won't need to turn the heat on til November or so.
Handyman, painter, wood floor refinisher, property maintenance in Tulsa, OK
Jeff Clarke,
My foam (SIP's) reduced my worst months heating bill from $500 a month to $127 a month. that inspite of making the home twice as large with twice as many windows..
(same furnace)
This summer the house was at least 10degrees cooler than outside sometimes 15 degrees..
as things cooled down it's remained 15 degrees warmer without the furnace on..
46 vs 72?
Not sure what that tells you at this point. Foam is not a heat SOURCE. LOL.
No amount of insulation will maintain a temperature differential indifinitely. My 76 build FG home is 70 to 74 degrees in the morning even with 40+ temperatures outside. If the day time temperature fails to hit 70, the house will cool to sub 70 over time.
I am not arguing against foam insulation. I am just not sure that an anacdotal story of 46 vs 72 tells anyone very much at this point.
No amount of insulation will maintain a temperature differential indifinitely. My 76 build FG home is 70 to 74 degrees in the morning even with 40+ temperatures outside. If the day time temperature fails to hit 70, the house will cool to sub 70 over time. I am not arguing against foam insulation. I am just not sure that an anacdotal story of 46 vs 72 tells anyone very much at this point.
I was going to make the same comment. My house in Maine has been experiencing low night temps in the high 30's for the last several nights, with highs during the days about 64-70. My new addition (fiberglass batts-six inch walls) has kept about 68-72 degrees without any heat, but we get a lot of solar gain through big south facing windows, so we do have a heat source, just not an internal one.
More on point is that the total building envelope will have a certain lag time in reaching a temperature equilibrium with the outside changes in temp. Heat sources in the home will have some effect on the amount of time it takes to reach that balance, but that is what is trying to take place. The beauty of foam is that you get the air sealing and insulation all during the installation. The air sealing may well be as an important an aspect of achieving a longer lag times in reaching temperature equilibrium as anything, if the total R values are the same.
Dave
I guess I should start by saying I have never really worked with sprayed in foam insulation other than trying to drill through it for gas lines and ended up going through a pile of hidden security wires. Having said thatI hate to be the fly in the ointment (or maybe a possible fly) about closed cell insulation.
A friend of mine has been a boat/yacht builder for about 25 years and he has repeatedly told me stories about how water logged closed cell insulation can get. He said that with age it becomes a sponge. Not what you would want in a multi million dollar boat or house for that matter. A month or so ago I was over at his place when he was actually trying to remove this stuff from the inside of the hull of a boat. He was right. It was a sodden mass.
He laughed and said that people still think that the stuff is good. If it lets AND keeps in water, it must let in air eventually.
I said that maybe it's the sea water that's doing it and he said no, it's condensation(fresh water) that accumulates.
Anyways that's the info. I don't know nuthin' and at my age I hope I'm not building another home for myself where I have to decide to use it or not.
roger
Foam can degrade, particularly through UV exposure. Closed cell foam is not 100% closed cell. The cells are formed by chemical reaction, and some percentage of cells will have weak spots that can open for a variety of reasons--they're formed open, or change in air pressure opens then, etc. I'm going from memory, so the specific number will be suspect, but closed cell foam can have as many as 5% or 8% open cells. (Imagine being the person assigned to count them!)I know a guy with a hunk of foam in a jar of water for perhaps 25 years now, and he does that to show that it does not get water logged. And it isn't.And yet you saw water-logged foam. And I know builders who've seen that when deconstructing a building. So how does it happen? Best guess to date is that vapor drive is the culprit. And that's why, because our houses use foam, we pay particular attention to controlling interior humidity, so that the conditions do not exist to "pull" the vapor out of the house through the foam. It's a tricky subject that is hard to explain in few words, so I hope I haven't confused things limiting myself to one paragraph.
so that the conditions do not exist to "pull" the vapor out of the house through the foam.
Cloud,
I find your choice of words very interesting
I have never heard anyone say "pull"
but if air pressure is moving from more to less then a "positive house" is not pushing...the universe is sucking???
Am I getting weird?
Yeah, you're getting weird. <G>I wasn't trying to be that literal. Apologies on imprecise choice of word. Systems try to balance. Temperature, pressure, moisture differences try to equalize if they can, unless something prevents that. Not trying to say other than that. For temp differential, we use insulation and mass. For pressure differential, we use vents and maybe fans. For moisture differential, we use dehumidifiers to keep from having a too large gap between the interior and exterior humidity, on the theory that if there is a significant difference, equalization will happen (in an air-tight house) by moisture being driven through the walls from the area of more moisture to the area of less, as allowed by the wall materials.That's my understanding at this point. I'm quite open to learning about it more and better.
Cloud, I was not trying to correct you at all....it just struck me as a very interesting way to think about things.... in a good way.
No, that was ok and a good catch. I was trying to be funny in response.
Here's the product NCFI - if you are interested - http://www.spray-foam.com/compare.html
Jeff
NCFI is North Carolina Foam, about an hour from me. I used their polyurethane on my house.My curiosity is about the effectiveness of the ERV's.
CH - we've only used the ERV in late summer conditions but I like it already. It has been ducted to deliver about 250 cfm fresh air to a second floor hallway (tempered and humidity-adjusted by exhaust air) - the main purpose is to avoid winter staleness since we have a combination of hydronic baseboard and radiant heating.
Outside air intake is via a quarter-round louver that looks like an attic window. I'm certain that the summer performance, especially setting it to run at night, pulling in and dehumidifying cooler nighttime air, has reduced our air conditioning bills.
Running 2 American Standard A/C units SEER 15 with Trane 'CleanEffects' air filters - like this setup a lot.
Jeff
It's definitely a challenge to explain all this in a paragraph!There are so many different types of foam and all have different properties. Obviously, not all are used for in spray in place applications. EPS, (expanded polystyrene) can absorb up to 4% by volume of water. Maybe thats the stuff that got waterlogged. I think it's used in those insulating white coffee cups, too. Extruded Polystyrene (XPS) has only a tenth of the absorption of water. Polyisocyanurate is in between. The other issue is permeance or how well vapor can pass into the material. I don't recall what Icynene uses, but if their literature is to be believed, a 5" thick layer has a permeance of 10, which is not a vapor retarder at all! Foil faced sheets of polyisocyanurate, on the other hand, have a permeance of less than 0.1. Man, the manufacturers of all this stuff don't make it easy. I have a PhD in Chemistry and I can't answer the simple question of whether to foam in place or foam sheathing on the exterior of conventional 2 x 4 with R-13 fiberglas.I do know my daughter got Icynene in the walls of her new home and the place is always comfortable even though her two sons always leave the doors open. Her bills are much lower than mine, too, and she lives just a few miles away.Frank
Excellent! You obviously know more about it than most.
Apparently there is more to using foam than we are led to believe. It's interesting how, for some reason, foam does and does not absorb moisture. I hope it isn't another urea formaldehyde problem.
roger
First are you sure that it is closed cell?Now there are different types of foams and those used in houses as closed cell are polyurathane. And I don't have any experience with them.But my dock is floated by XPS and if it absorbed water it would be sitting on the bottom of the deck.Now open cell EPS will absorb water if it is submerged in it. But it is a slow process.Based on my experience is why I am asking if you are sure that it was closed cell.Also a boat is much different than a house.The water is trapped inside until the bilge pump is run..
.
A-holes. Hey every group has to have one. And I have been elected to be the one. I should make that my tagline.
I dunno. He called it closed cell insulation and where he was taking it off when I saw him was on the walls. I don't think there is too much standing water on the walls.
I wish I had taken a closer look at the stuff but I was only noting how wet and heavy it was. You are right about different foams and I think the house foams look pretty dense when you break it apart where the boat stuff looked more bubbly (technical term that). I have to ask him what the chemical name for it is. He said he would never used closed cell foam in any house. He builds fantastic EXPENSIVE
boats but I don't believe he knows much about houses though.
roger
The inside of a very well insulated house can EASILY stay warmer than the exterior air temp all winter with a little solar gain.
Remember how many heat sources there are in a house, even when the heating system is not on: the refrigerator, light bulbs, electric motors, computers, TVs, human beings, pets ... Not to mention solar gain through windows, as several others pointed out.