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12 Answers

Has anyone had experience with the Unico small duct system?

I was looking at the top finishers for the department of energy's "Race to Zero Student Design Competition" ( http://energy.gov/eere/buildings/2015-results ) and found the winner used the Unico system. http://www.unicosystem.com/the-system/how-it-works/air-handlers/. I recall actually being in a home in Chattanooga once 15+ yrs ago that I believe had one of these systems, but I really know nothing about them. With the problems associated with finding small enough systems for well insulated homes and cost effective systems...does anyone know if I should be looking at this as an alternative?

In Mechanicals | Asked By Andrew Bennett | Apr 29 15
8 Answers

Does leaving a service cavity on the inside of a double stud wall make sense?

Would there be anything wrong with the following assembly? From exterior to interior: Siding, furring, rigid insulation, sheathing (air seal and WRB), 2x4 stud wall, gap, netting stapled to inner studs. 2x4 stud wall, and finally drywall. The outer 2x4 stud wall and the gap would be filled with cellulose, but the inner 2x4 stud wall would be empty to allow easy wiring and plumbing.

This design seems to have some clear perks. Removed thermal bridges. You get a service cavity. The inner wall supports the netting, so it won't need excessive stapling.

In Energy efficiency and durability | Asked By John Ranson | Aug 27 15
7 Answers

Does an 850-square-foot house have to have return air ducts?

I live on a slab one story home. I currently have an old forced air gas furnace that I would like to get replaced as well as install central air conditioning. I had a local contractor come out and quote a complete system and was told I would need all new ducts because I didn't have a return air system. The furnace currently is in a central closet with a large air grate on the side letting air back to the furnace. It is right in the middle of the house and I usually leave all doors to all bedrooms open. He quoted me $12000 for the whole job.

In General questions | Asked By Brett Obraza | Aug 27 15
9 Answers

Wall stack up opinions - using rigid foam as air barrier between double stud wall?

Hi,

I'm in climate zone 6A looking to build a partition wall between an attic bonus room. One side of the bonus room will remain as cold storage, and the other side will be heated by minisplits and resistance backup. I'm looking at building a double 2x4 wall separated by rigid foam. The exterior wall would be framed 24" o.c. to maximize insulation. There will be no plumbing or wires in the exterior wall. The interior framed 2x4 wall will be framed 16" o.c. and will contain wiring, and will possibly be plumbed for a sink.

From cold to warm, here is what I'm proposing:

In Energy efficiency and durability | Asked By Rick Van Handel | Aug 24 15
7 Answers

Anyone familiar with Insultex house wrap?

I was wondering if anyone had any thoughts on this house wrap - http://www.insultexhousewrap.com/

They appear to be making some exaggerated claims and I am not certain that the R-value claimed would be possible.

Any thoughts?

In Green products and materials | Asked By Marcus Sheffer | Jul 31 15
3 Answers

Opinions sought on window details

Building a "good" house in zone-5.

Current plans are to use 2x4 framing with plywood sheathing, then two 1" layers of reclaimed foam, 1/2 thick furring for a rain screen and hardiboard siding.

I have a builder willing to do this and we are discussing window details. The windows are 5" thick and come with either an installation fin in the middle or no fin and you use straps to attach the windows.

In Green building techniques | Asked By Michael D | Aug 27 15
4 Answers

My project is insulating a 54 x 72 x14 pole barn in southwest Michigan

My project is insulating a 54 x 72 x14 pole barn in southwest Michigan.

I was able to purchase 4' x16'x 2" EPS foam sheets with foil on one side for a very reasonable price, (small imperfections) from a near by manufacture. I installed it in the walls, foil side...

In the ceiling I installed the EPS in the 4' space between the trusses, foil side down facing the interior, it will be covered with the interior steel liner and 14" of blown in insulation will be above. The building has a concrete floor with drains. I plan to heat with LP gas (infrared tube heaters).

In General questions | Asked By Michael Schumacher | Aug 27 15
1 Answer

POLE BARN INSULATION/VENTILATION ADVICE

Editor's note: This is the second posting by Michael Schumacher on this topic. GBA likes to have all follow-up questions on the same thread, so the contents of Michael Schumacher's second post have been moved to the original thread. Here is the link to the original thread: My project is insulating a 54 x 72 x14 pole barn in southwest Michigan.

In General questions | Asked By Michael Schumacher | Aug 27 15
15 Answers

Humidity control

I operate a facility where humidity control is very hard. The building is 6 yrs old, built well, but cant control the humidity. We have resealed return duct, replaced tstats, added attic exhaust fans, etc. But still the building humidity matches the outdoors as fast as it changes. We try to keep the building 72f and it feels like you can't breath and hot. Mildew forms. We keep the building 68f you can breath, but freeze and smells like a basement, and mildew forms. All exhaust fans are working, and ceiling fans are on.

In GBA Pro help | Asked By clark jones | Aug 24 15
1 Answer

Furring strips or another layer of sheathing over foam?

I am in the process of framing a house 2x6, 24”oc. The house will be sheathed and taped with the Zip system and 2-1” layers of rigid foam (staggered seams and taped). Over top of the foam, I planned on using 1x4 or ripping down ¾” ply for furring strips to both hold the foam and attach the vinyl siding too.

In GBA Pro help | Asked By Brian McDonald | Aug 27 15
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