Exterior insulation on crawl space or ??
Bruce
| Posted in Energy, Heating & Insulation on
I fully buy into the idea of insulating the exterior of concrete walls when they’re heated on the inside, but I cannot come up with a good reason to do so on the stemwalls of a ventilated crawl space. This is in an area with real winters. I’ll do a good job insulating the rim joist bays and under the floor, w/ appropriate barrier, etc.
Any other opinions?
Formerly BEMW at The High Desert Group LLC
Replies
Haven't seen any of them insulated around here. Maybe in Montana or Maine...
Any jackass can kick down a barn, but it takes a carpenter to build one.
How are you keeping your plumbing pipes from freezing? Are you depending on heat leakage from hydronic pipes or ductwork?
With the exception of waste lines, there won't be any plumbing below the bottom of the joists. Fairly typical from what I've experienced. I had a previous house with a wet crawl space, and small puddles in it would ice over in the winter. No problem with plumbing though.Formerly BEMW at The High Desert Group LLC
Bruce,
Here's a peek at FHB Issue #162, Dr Joe Lstiburek's Top Ten Dumb Things to do to a Building...
#10 Ventilated Crawlspaces...
"A crawlspace is just a mini-basement and should be treated as such. Seal the vents, insulate the perimeter and cover the floor with a vapor barrier".
It's easier to insulate the walls than the floor (rim joist insulation continues down, no right angles, fewer square feet of insulation too), and by doing so, you create up a big hunk of space for plumbing and ductwork.
In Issue #160, I'll have an article by Scott Gibson with input from leading building scientists on insulation systems for particular projects. Good, Better and Bad for basement/crawlspace, walls, and roof/ceiling.
Stay tuned and I hope it'll help you.
One happy assistant editor
Edited 8/13/2003 3:17:14 AM ET by Dan Morrison
I recall those articles; thanks for sending the issue numbers. Wile I remember when reading about sealing up the crawl space vents, there's the code issue to deal with, and frankly, aI'm not gonna get into that with the local inspection department. I need to have the vents to conform. It comes down to whether I'm going to close them all the way in the winter or not.
As it turns out, I'm going to have to add 2" of rigid foam plank from the top of foundation down to below grade for finish purposes ... house will be stucco, and I'll put a 45 egree chamfer at th top of the foam creating a ledge which will be stucco'd over, right down to grade. So at least I will not have bare concrete exposed to the cold. And in the areas of the lower level that are completely backfilled, against the uphill side of the house, I also have the 2" foam on the exterior.
Formerly BEMW at The High Desert Group LLC
Edited 8/13/2003 8:48:31 AM ET by Bruce