oops, used tekfoil
Last Post 11 Sep 2007 12:31 PM by Gary W.. 1 Replies.
Printer Friendly
PrevPrev NextNext
You are not authorized to post a reply.
Author Messages
hamboneUser is Offline
New Member
New Member
Send Private Message

19 Aug 2007 06:43 AM
Wouldn't you know the day after we finished our third concrete pour of three for our 44x56 barn restoration project in central Maine, I would find this website saying tekfoil under the slab on grade is NOT the way to go. After much research we decided to use tekfoil(foil,bubble,bubble,white poly) under our six inch slab. We did haul in about 700 yards of good gravel to sit the foundation on. We put radiant floor tubing in two zones, one of which(12x56) is going to be an apartment. The rest of the barn we put the tubing in just for the future so it would be there. We put 1" styro all around the outside edge, the thickness of the exposed slab. We hope to heat it with four 4x10 solar panels and a wood boiler. How can we make the best of our situation now?
Gary W.User is Offline
New Member
New Member
Send Private Message

11 Sep 2007 12:31 PM
It’s unfortunate that you spent some extra money on what amounts to a very expensive thermal break, but look on the bright side of things; it’ll also act as a great vapor barrier and it’s a whole lot better than using nothing at all. Heat losses to the ground are greatly influenced by soil composition, density and water table. The fact that you used 1” of XPS around the perimeter is encouraging and the most important detail you could have done. 2” would have been better given your climate, but more is always better. Many schools of thought about how important it is to have full coverage on medium/large sized slabs. Good foam-board insulation isn’t cheap or easy to work with. Because budgeting factors can sometimes make or break a radiant job I feel that (sometimes) it’s ok to compromise a little and go without, but I do push for full coverage because of the payback over time and the radiant slab is something that will outlast the life of the building. We have only one chance to get in there. I think you’re in good shape though. The only ill effect you may experience could be longer response time & perhaps the hassle of throwing few extra logs into the wood boiler. Programmable setback thermostats won’t work so well on such a high mass system but outdoor reset will.
Wallace Radiant Design
You are not authorized to post a reply.

Active Forums 4.1
Membership Membership: Latest New User Latest: EverlastCT New Today New Today: 2 New Yesterday New Yesterday: 2 User Count Overall: 30348
People Online People Online: Visitors Visitors: 186 Members Members: 9 Total Total: 195


Welcome to GreenBuildingTalk, the largest, most active forum on green building. While you can browse the site as a guest, you need to register in order to post.

Register Member Login Forum Home

Search Directory

Professionals Products

Get Free Quotes

Tell us about your building project and get free quotes from green building professionals. It's fast & easy! Click here to get your free quote.

Site Sponsors

For Advertising Info:
Call 866-316-5300 or 312-223-1600

Professionals Serving Your Area:


Read the latest GBT Newsletter!

Copyright 2011 by BuildCentral, Inc.   Terms Of Use  Privacy Statement  Free Quotes  Professional Directory  Advertising Programs