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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.

In GBA Pro help | 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.

In Green building techniques | 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:

In Energy efficiency and durability | 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.

In Energy efficiency and durability | Asked By Matt Berger | Jul 22 15
0 Answers

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In General questions | 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.

In General questions | Asked By Clay Whitenack | Jul 23 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.

In General questions | Asked By Brad VanVickle | Jul 23 15
14 Answers

I need advice on the design of an energy-efficient heating system

Just completed re-framing a home in NH. Used Zip R on the outside, CC foam inside. I had planned on going with radiant heat but from the articles in GBA, this may be overkill. I have spoke with a few propane companies and 2 plumbing companies and have not seen anything that is right. Most do not seem to be up to date ( old school) Who out there can I contact to design the proper system without trying to sell me on their systems?

I am truly thinking of going with return hot water as this system has served us well in our last home for 25 years.

In Mechanicals | Asked By Joseph Maraldo | Jul 22 15
5 Answers

Managing humidity in a tightly constructed ventilated house

In a tightly built, newly constructed house in Zone 5, we're experiencing higher than desired humidity. As expected, the air conditioning does not run often enough to effectively dehumidify, even in the peak heat of an Illinois summer. I'd value your recommendations.

Here are some specifics:

In Mechanicals | Asked By Dave Brooks | Jul 23 15
4 Answers

Radon mitigation

Two story residence in WV with cold winters, mostly hot, humid summers, HVAC on both floors and lower level mostly below ground level. Plastic under concrete floor and some insulation on basement level walls. House is rather tight construction for the 70's construction.. Have an installed pipe from below basement concrete floor to above roof with in-line radon fan. Had minimal effect on radon reduction which is at or just above recommended levels to take action. Intend to add exhaust ports in that stack in basement hallway.

In Energy efficiency and durability | Asked By Virgil Tacy | Jul 20 15
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