I've heard that spray on foam can now be a DIY project. I've seen the little bottles, kits as they are advertised, but I've heard the professional stuff is available for rent and with due care a homeowner can use.
I'm interested in doing my floor boards. Several obstacles are stopping me. 1) I need a source. 2) I'm unsure of SPF can be applied in subfreezing weather 3) I'm unsure of the implications of encasing everything that runs inbetween my floor joists (plumbing, electrical) in SPF is a good idea.
Pros: 1) might not be too much more expensive than batts. 2) I'll spend a lot of time cutting batts around obstacles (joist braces too) 3) I'll get a better R value out of it.
Thoughts?
TIA,
Bill
spray foam has almost double the r value of anything out their! If you are trying to insulate the floor joist I would not waste the time or money you will never recoup the money!
I'm confused are you saying spray on foam is a waste of money or insulating floor joists in general?
Do you have a crawl space or a full basement???? if crawl space do the walls but not up in the floor joist. I think you will find the cost is very high for foam.
I have a crawl space.
The small cannisters are quite $$$. I do not realistically expect to use them, however an online friend from a while ago said he rented the equipment and the cost was quite reasonable. I'm just not sure where to look or if renting this type of equipment is common. Nor do I know if it can be done in the cold, but since it's (usually) not water based I imagine so.
I would rather do the floor joists than the foundation walls because I will then block ventilation from my crawlspace and moisture inevitably becomes a concern.
I will then block ventilation from my crawlspace and moisture inevitably becomes a concern.
Thats that wrong way to go. Go read
http://aboutsavingheat.com/crawlspace.html
Insulation on the wall and a 6 mil poly on the ground over lap it 2'and tape all seams.
Read the article. I can see where a vapor barrier on the floor is a good idea. I had a previous house with that. However there are ventilation grates along the foundation. I've got to think they are there for a reason. To insulate the foundation walls still makes little sense to me if I'm going to leave those vent grates operating. The article does not mention this. (unless you are saying by putting the poly over the floor I can close off the vents - is this true?)
This leads me back to insulating the floor joists. Trust me I'd rather not. I'd much rather do the simpler method of the foundation walls. I'm still not understanding the ventilation part though.
Thanks,
Bill
Bill,
Have a pro look at your problem and then work out a solution for foam. Spending $ here on the install but you'll recoup over the years w/ heat saved.
We have had to go back in and take out the insulation up in the floor joist . In so many homes as it just dont work. If you did go to that www. it said close the vents. The crawl space works as a heat sink . We always put small registers in the duct for down there. Homes did that way always use less fuel. l
OK I'm with you Ed, but do you think I just need a return air vent would work better to control humidity than just a supply?
PS... I can still put the vapor barrier down but most of the crawl space has a concrete floor. It's broken in parts but appears to have at least a foot of sand, if not more. I'm wondering if the plastic down on it is useful or a waste.
Thanks again. I think I'm figuring this out.
Bill
Dumb Me If you have the duct down there we put 2 small register outlets and one small one for a return. In some test homes they have did.This way saved about 12% on fuel.
Dont forget a R19 block of fiberglass in every joist space all a round the home up there on the sill plate.
For what it cost for the poly put it down.
Originally Posted by bill()c
I've heard that spray on foam can now be a DIY project. I've seen the little bottles, kits as they are advertised, but I've heard the professional stuff is available for rent and with due care a homeowner can use.
I'm interested in doing my floor boards. Several obstacles are stopping me. 1) I need a source. 2) I'm unsure of SPF can be applied in subfreezing weather 3) I'm unsure of the implications of encasing everything that runs inbetween my floor joists (plumbing, electrical) in SPF is a good idea.
Pros: 1) might not be too much more expensive than batts. 2) I'll spend a lot of time cutting batts around obstacles (joist braces too) 3) I'll get a better R value out of it.
Thoughts?
TIA,
Bill
On this web there are sites that sell or distribute SprayFoam (Slow Rise-SR) a two cylinder kit that covers 600 sqft costs about $715 plus shipping about $50. comes out to be about $1.30/sqft then you have to spray it. I found a place in Lousiana that applies their product for $1.25!!!, and they have an excellent rating with the BBB (www.greenbeaninsulation.com).
The temp of the cylinders has to be between 75-85 degrees when applied, and can be warmed inside and they claim that once warmed they retain their heat for a long time(?).
I've also looked into this. I want to insulate my garage and eventually my whole house w/ spray in foam. I think one of the DIY suppliers (self contained kits)was TigerFoam or something like that. All of the suppliers $ were about the same, $1.15-$1.30/square ft. Keep in mind you'll probably need a couple inches to get a good R value. They all sell there product claiming by square foot or by cubic foot. With spray foam insulation a square foot is considered 12x12x1. For a 2 cover you'll have to take you're square footage X2 to get the volume you'll need.
3 MAJOR advantages of spray in foam are:
1) complete vapor seal
2) excellent R-value/
3) speed of instalation
(among other advantages, rot resistance, vibration absorbtion/deadener)
This may be one instance a pro is a better option. IF YOU CAN FIND THEM CHEAP ENOUGH. At $1.25/sq ft like above, or even $1.50 and with a good reputation, I'd go with the pro. They probably get the material MUCH cheaper, do it faster, and have already worked out the technique. Personally I don't trust BBB ratings, you need to talk to previous clients, both bad and good revues.
On the other hand, if you can't find a contractor with a competitive price, just want to get the experience, or there are no contractors in your area, I think the DIY is the way to go. Do a couple practice sprays first. (I recently turned my Dad, a General Contractor in Wyoming on to this DIY foam. There are no contractors in the area that do it, so they have to ship 'em in from other areas, $$$$)
Personally I would be a little nervous about renting the equipment, afraid I'd ruin it and end up paying for it.
I'd also put markings on the joists and take pictures before of where all of the mechanicals are located.
As for insulating crawl space I've never done the floor. We always used rigid foam on the inside of the walls, then cut removeable rigid foam (2+) pieces to insert in the grate openings during cold months, and put down thick mil poly on the floor.
I'd be interested to know what you decide and how it goes.
JC
have you, has any one used or considered using the European style multi foil layer insulation, like Airtec but more technologically advanced. There are several available, like SF19 Superfoil Quilt, Actis Triso, Superquilt, its like they use on space craft, and as I understand it was developed from the French Space Progamme , its whole lot of bucks as it works out to $2.50 sf but if its good enough for NASA types it should be value. It based on reflecting radiation rather than conduction or convection.
I dont think there is a perfect product, one that fits all situations, so you have to use which suits each part the best, thats the pocket book, the amount if work required, the value achived.
Spary polyurethne is great, its also most insulation for least volume, but once its in its in so dont get it places you dont want it. Trimming and clean up can take time and there is waste from the trimming.
Funny you mention it, I am considering the foil insulation. You're right, it seems pricey (apr $50/2'x25' roll or $100/4'x25' roll)(apr $1.00/sq ft, actually pretty good). That was the price at my local Lowes, about the same I found online. I haven't seen the stuff you're looking at, $2.50/sq ft, probably thicker than the 3/8 stuff I'm looking at. I'm considering it for insulating the inside of my garage door. As the garage door will be replaced in the next few years I don't want to spend big bucks on permanent instalation. With the foil if I staple and tape it, I can reuse it. Me being a bit of a tightwad, I started brainstorming alternatives (because of the price). I came up with using foil space blankets that you can get at most sporting good stores, as the face and back, then some combination of bubble wrap and/or foam batting (from the fabric store). I haven't got as far as pricing and making sure it would work. It probably won't be as good as the actual product, but its gotta do something.
That stuff (foil insulation) is pretty cool, though. You can get up to R-14 in 3/8.
JC
Foil is only effective for radiant heat, in space this makes sense as there is no air movement (convection) because of the vacuum in space.
While it is somewhat effective here on earth all claims made by proponents should be taken with a grain of salt as it's not really effective against conduction and convection heat transfer.
Hi
Don't know much about your problem, but just yesterday I used a polyurethane spray on foam kit to insulate my Rim/Band joist areas. I have to say, it worked out great. The foam is made by fomo and called handi foam, tiger foam makes the exact same product and i think it may all be the same manufacturer. Anyways, after preping, I had to put a space heater on both tanks (propane size, 60lb each) for 2 hours. Once their around 75 to 85 deg you can spray. It sealed everything perfectly. In fact with the 600 board foot kit, I got all the joists done in about 25 minutes, it dries in about a minute and I still have 21lb, 1/3 of the kit left over. It is a bit messy though, so wear gear. Very little odour and no flamability issues when spraying. just keep some ventilation going.
Check their web sites if your interested.
Mike
Tags: spray, foam, spray foam, crawl space, floor joists, floor joist, foundation walls, good idea, they have, about same
