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4 Answers

Insulating interior wall over brick in Phoenix

I have a home in Phoenix built in 1958. All exterior walls are brick and there is exposed brick for interior wall surfaces of those walls.

This is fine, except in one bedroom which gets alot of sun on its two brick walls (the other two walls are interior and are stud/drywall). In summer this bedroom is 5-10° hotter than the rest of the house, and the walls are warm to the touch. I've even tried putting a special vent fan faceplate to move more cold air in there- it only helped slightly.

I'm considering insulating the interior of the two brick walls in this room. Two questions:

Asked By Shawn Us | Jul 23 15
1 Answer

Gray/ grey water system in Southern California

I am new to GBA so bear with me if this has come up before. I am in Southern California with severe drought conditions. I think I have a good arrangement for a greywater system- One story house on a medium slope hillside so my crawl space tapers from 2 ft. to 8 ft. Great for dealing with the utilities. It also might be great for natural drainage of a greywater system. I was wondering if I put a large pool size sand filter inline if I could let the water drain through into a say 100 gallon holding tank and use a submersible pump attached to the drip system and/ or perforated pipe drainage.

Asked By Richard Stutsman | Jul 23 15
1 Answer

Flat roof insulation?

I am converting the sun room to a bedroom
My concern is about the ceiling insulation and ventilation.
the roof is flat and not insulated at all.
The previous owner blocked all air flow from soffit using pieces of wood which also supports the roof.

During the summer time, the asphalt flat will be stressful because of no air flow.

Asked By Mansig yoon | Jul 23 15
14 Answers

What is the most practical air sealing technique for new construction?

I am building a home in climate zone C4. My wall assembly will consist of 2x6's on 24" centers, OSB sheathing, then a layer of 1" XPS insulation, with my wrb on the outside of the insulation. I will then have rough cut reverse board and batten siding.

Asked By Kail Zuschlag | Jul 14 15
5 Answers

Fixing a central-fan-integrated supply ventilation system

I'm in climate zone 4A (VIrginia). My house has an upper and lower HVAC system. The lower system has a central-fan-integrated supply ventilation, roughly like the first diagram in this document:


[Editor's note: It appears that the poster intended to include a different link -- this one: Central Fan Integrated Supply Ventilation—The Basics]

except that:

Asked By Joe M | Jul 20 15
8 Answers

Fujitsu 12RLS3H in -25°F weather?

Does anyone have experience with running a Fujitsu 12RLS3H in -25°F weather, 5-6 hours a day for 8 weeks? I live in zone 7.

Asked By Matt Berger | Jul 22 15
0 Answers

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Asked By diksaTrils diksaTrils | Jul 23 15
5 Answers

Cost effectiveness of one thick layer of rigid foam vs. two thinner layers?

Hi all,

We live in Central KY, zone 4a. We are shooting for a "pretty good house" standard for approximately r-30 walls. We are leaning toward a 2x6 frame construction, with blown-in cellulose, plywood or osb sheathing, a couple of inches of rigid foam, and brick veneer.

I see that it is most energy efficient to use multiple layers of exterior rigid foam so that you can stagger the seams. However, this obviously doubles the labor cost of adding the foam.

Asked By Clay Whitenack | Jul 23 15
20 Answers

Buyer education versus a good code and intensive enforcement of it

This is kind of a general question. I'm seeing more and more issues coming up on GBA questions and answers regarding shoddy construction that homeowners are having to deal with. I read it recently in Peter L's description of some builders in the Phoenix area. This is most concerning when one is having a new home built, or purchasing a previously built new home, and it has subpar construction.

Asked By Eric Habegger | Jul 21 15
3 Answers

Drying to the inside question

On homes with rigid foam on the outside of the walls, I know the house has to dry to the inside, so just latex paint or possibly a "smart" vapor barrier would be used on the interior drywall walls. My question is regarding the ceiling. I would probably be using blown-in celulose or similar (just a "normal" attic with ridge-vents and vents in soffits, etc), so would I want to poly the ceiling to keep the moisture out of the insulation? Can the house still dry to inside with poly in the ceiling?

Build will be right on the border of Zones 6 and 7 in Central MN.

Asked By Brad VanVickle | Jul 23 15
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