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24 Answers

New slab with radiant heat

As part of our remodel north of San Francisco (ZIP code 94941), we are converting about 700SF of our lower level into living space. The existing slab has been removed we excavated a few additional inches to increase our ceiling height, and we are getting ready to put back a new 5" slab, in which we will also add radiant heat tied to the rebar.

Asked By Torsten Budesheim | Apr 22 16
8 Answers

Can someone explain the science behind mid-wall vapor barrier on a double stud wall?

In order to save money, I've switched my wall assembly last minute from using exterior rock wool board to a double stud wall construction. I would like to speak with my county inspector about using this approach to make sure I don't have problems during construction. I'm struggling to understand how I'm going to explain how a vapor barrier on the back side of the inside wall is a good idea.

I'm in climate zone 5, and here is my intended wall assembly:

From inside-to-out:
GWB
Insulweb netting (affixed to stud to hold cellulose)

Asked By Adam Peterson | May 4 16
6 Answers

Paint as an Air Barrier

CZ-4. Net Zero Energy Slab-On-Grade Ranch. Planning for 0.1ACH50. Huber Zip-R sheathing.

Asked By Ted Cummings | May 2 16
6 Answers

Is this my best foundation choice?

First off, Green Building Advisor has been invaluable in my research to design my future home and have found it well worth the membership cost. So thank you, to all you who have made this site what it is.

I am planning on building a 1700 sq ft ranch style straw bale house near Cortez Co (climate zone 5B). Currently I am sketching up layouts, making lots of notes on building techniques, choosing home fixtures (doors/windows), HVAC systems and researching different build options, before I take my plans to an architect so he can refine and incorporate them.

Asked By Ken Hodge | Apr 29 16
1 Answer

A temporary situation for new people registering on GBA

As our I.T. team tries to find a good way to block Chinese companies which have been flooding our site with spam, we need to temporarily stop accepting new registrations for the GBA site. (I'm talking about the free registration that is necessary before you can post a question or post a comment.)

We anticipate that this situation will only last for a few days. Once we get a handle on a way to fix the spam problem, the site will once again accept new registrations.

Anyone who wants to become a GBA subscriber can still subscribe at any time.

Asked By Martin Holladay, GBA Advisor | May 2 16
11 Answers

Exterior rigid foam and re-siding project

I'm seeking input and opinion. I'm looking to re-side with the dread vinyl (need the low maintenance for my two story house). My 40 year old post and bean house has interior sheetrock, 3.5" of fiberglass batt insulation with kraft paper, rough cut full 2x4 studs on 24" centers, plywood sheathing (I think 5/8"), paper (a mix of Tyvek and felt), and cedar shingles. Shingles and paper will of course be removed, sheathing inspected in the process. I'm in zone 6.

Asked By Howard Gentler | May 2 16
3 Answers

Interior vs. exterior air barrier

Wondering what the consensus is on the interior vs. exterior air barrier issue is? I am considering this question in light of a double-stud, dense-pack cellulose wall.

Marc Rosenbaum has indicated that he prefers exterior air barriers, because they are so much simpler to execute (no zig-zagging around floor systems, etc).

Asked By Burke Stoller | May 4 16
5 Answers

How does efficiency in a mini-split vary over various operating levels?

It is my understanding that a SEER rating is determined by simulating the operation of a particular make/model air conditioner over a hypothetical season, presumably assuming various temperature and humidity levels throughout the year.

Asked By david jensen | May 3 16
8 Answers

Economical, Long-Lasting, Flexible Sealant

CZ-4. Net Zero Energy Home. New Construction Ranch . Concrete Slab-On-Grade. Planning for 0.1ACH50. Using Huber Zip-R panels with (1"PolyIso laminated to the OSB).

Asked By Ted Cummings | May 2 16
2 Answers

Slab — thermal break at vehicle roll gate

as I mentioned in a previous post we are putting in a new floating slab on grade in a warehouse building.

the grade has been leveled and sewer drains in trenches and backfilled
then there is a 4-6" layer of compacted gravel and we plan on using a 15mil taped vapor barrier and 2" of taped 60psi XPS on top of that.

for a thermal break we are using 2" 25psi XPS that extends 10" below the slab

there will be radiant installed throughout the building and we are in

my main question is:

Asked By Big Ern | May 2 16
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