Crawl Space Insulation

Jared · 11-13-2009, 06:29 PM

My house is on piers and a perimeter footing. The crawl space is completely exposed to the outside. I've read alot of stuff from buildingscience, but alot of the homes that are discussed are built on slabs. I am of the inexperienced opinion based on what I've read that sealing off the crawlspace with some sort of skirting would be the best option for insulating the floor. At first thought I figured I would just build a wood frame skirting upon which I could hang some rigid foam and fiber glass batt. However, the house sits on H-blocks that are spaced around the perimeter. Any skirting would have to either be built in front of these or there would have to be a space to accommodate them. I like the idea of sealing off the crawlspace from drafts, water/humidity, and temp. What are your thoughts?

DangerMouse · 11-13-2009, 06:33 PM

Hi and welcome to the forum. do you have any photos?

DM

**Gary in WA** · 11-13-2009, 06:58 PM

Did you read this one with bad, good, and best?: http://www.buildingscience.com/docum...n-crawlspaces/
Be safe, Gary

Jared · 11-13-2009, 07:31 PM

Thanks and no, I don't have any photos, Mouse. Gary, that website is full of articles, so no I didn't read that one. Looks good though, I'm gonna read through it. Thanks for pointing that one out

. Jared.

Jared · 11-13-2009, 07:44 PM

Figure 7 in that article looks like the way to go, but I think I'll try to use foil faced batt insulation instead of rigid foam. Working around the piers with the rigid foam would be a major pain, not to mention the plumbing.

**Gary in WA** · 11-13-2009, 09:49 PM

"Figure 7 in that article looks like the way to go, but I think I'll try to use foil faced batt insulation instead of rigid foam. Working around the piers with the rigid foam would be a major pain, not to mention the plumbing." --------- The rigid foam isolates the joist bottoms from the outside temperatures. This lets the moisture head to them and deposit water there. It would not be effective substituting batts, that would compress when installing soffit boards or house wrap.

My house has a vented crawl (which I close in Winter) with 5-1/2" joists and faced batts (facing heated) held up with wires. I'm buying 1" foil faced rigid to rip into 1-1/2" wide by 8' strips to install on the bottoms of the joists. To keep the joist bottoms from reaching the below air's temperature. Then I will install house wrap with sealed joints with insulated (rigid) rim joists underneath. I have 6mil plastic on dirt but unlike you my joists are 12" from the ground. The beams are on bricks, on concrete (circa 1910). Nothing but fun for a +60 old man. lol.
Be safe, Gary

11-13-2009, 06:29 PM	#1
Jared Newbie Join Date: Nov 2009 Posts: 3	Crawl Space Insulation My house is on piers and a perimeter footing. The crawl space is completely exposed to the outside. I've read alot of stuff from buildingscience, but alot of the homes that are discussed are built on slabs. I am of the inexperienced opinion based on what I've read that sealing off the crawlspace with some sort of skirting would be the best option for insulating the floor. At first thought I figured I would just build a wood frame skirting upon which I could hang some rigid foam and fiber glass batt. However, the house sits on H-blocks that are spaced around the perimeter. Any skirting would have to either be built in front of these or there would have to be a space to accommodate them. I like the idea of sealing off the crawlspace from drafts, water/humidity, and temp. What are your thoughts?

11-13-2009, 06:33 PM	#2
DangerMouse the Musigician Join Date: Jul 2008 Location: I'm right here! Posts: 10,404	Crawl Space Insulation Hi and welcome to the forum. do you have any photos? DM __________________ [SIGPIC][/SIGPIC]Click To view links or images in signatures your post count must be 10 or greater. You currently have 0 posts. to see some of my original magic tricks and trick boxes!

11-13-2009, 06:58 PM	#3
Gary in WA Moderator Join Date: Mar 2009 Posts: 8,851	Crawl Space Insulation Did you read this one with bad, good, and best?: http://www.buildingscience.com/docum...n-crawlspaces/ Be safe, Gary __________________ Clothes taking longer to dry? Clean the dryer screen in HOT water if using fabric softener sheets. They leave a residue that impedes air-flow, costing you money. Clean the ducting in the last six months? 17,000 dryer fires annually!

11-13-2009, 07:31 PM	#4
Jared Newbie Join Date: Nov 2009 Posts: 3	Crawl Space Insulation Thanks and no, I don't have any photos, Mouse. Gary, that website is full of articles, so no I didn't read that one. Looks good though, I'm gonna read through it. Thanks for pointing that one out . Jared.

11-13-2009, 07:44 PM	#5
Jared Newbie Join Date: Nov 2009 Posts: 3	Crawl Space Insulation Figure 7 in that article looks like the way to go, but I think I'll try to use foil faced batt insulation instead of rigid foam. Working around the piers with the rigid foam would be a major pain, not to mention the plumbing.

Crawl Space Insulation