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1 Answer

does part of attic that covers deck need to be insulated to prevent frost buildup?

the attic over the rest of house is insulated with vapor barrier and doesn't have frost buildup. What needs to be done to prevent frost in attic area over open deck?

In General questions | Asked By Linda Walker | Jan 16 17
23 Answers

New earth sheltered PAHS construction

I would like all opinions regarding my new home construction project. I have a full 3 days experience learning Sketchup and have managed to put several ideas on paper. Please review my plans...and pick holes in them :). I don't guarantee to change my mind, but I do promise to research varying opinions thoroughly and supporting data would be appreciated.

Mixed humid climate Missouri 39 deg latititude
CoMo HDD 5173
CDD 396
Sunny days 195
Humidity ave 70% 83% AM, 56% PM
111 days rain for 46"/yr
10 days snow for 14"/yr

In Plans Review | Asked By Laurel Davison | Nov 28 16
15 Answers

Lunos e2 ductless HRV system vs. ducted system

I am building a net zero house, 2000 SF, 2 stories. Can you tell me the pros and cons of the Lunos e2 ductless HRV system vs. a ducted system? The rep told me that 3 pairs of the Lunos e2 would be about right.

In Mechanicals | Asked By Courtney McCracken | Dec 8 16
18 Answers

Dry heat myth?

Every now and then, I hear people refer to how nice the heat is from a wood stove in our climate (marine zone 4), because it produces such a "dry heat." Whenever I hear that, I think to myself "combustion actually produces moisture, so I don't think wood stoves are particularly dry." I reason further, in my mind, that the only drying effect a wood stove may have on the interior humidity of a home would likely be a result of the tendency for wood stoves to grossly overheat one area of the home, which would drastically reduce the relative humidity in the air, thus averaging out to reduce th

In General questions | Asked By Burke Stoller | Jan 11 17
58 Answers

Mitsubishi minisplit 8-head system is not keeping up

Back in mid-November 2016, we had a Mitsubishi Hyper Heat MINI Split installed in our house after opening up the first floor of our home and installing some beams to make it more open. We lost duct work feeding the second floor, and had to come up with a solution. We decided on a Mitsubishi ductless system, since I had a smaller version installed in our detached garage and was very happy with it. My uncle did the garage, while I went with one of the Mitsubishi Diamond Dealers to handle our house. After 3 quotes, we decided on a company and proceeded.

In GBA Pro help | Asked By Andrew Simpson | Jan 6 17
5 Answers

What is correct installation of rigid foam board on roof, at seams of each panel?

What is the correct means to seal the seams between foam board applied on top of roof sheathing? What is the impact of incorrect sealing? Background: we contracted with a roofer to apply 4" of Atlas nailbase on top of the roof sheathing, before shingling. I happened to look at the roof on a recent cold morning and noticed gridmarks on the roof, indicating areas where frost had either melted, or had not formed, due to heat loss between the seams of the nailbase. I would think if the seams had been sealed correctly there would be no visible frost lines.

In Energy efficiency and durability | Asked By Jim Berry | Jan 11 17
4 Answers

Soffit vent with spaced boards and hardware cloth

I'm figuring out how I want to vent sloped soffits under a shed roof. I'm considering stapling galvanized hardware cloth across the bottoms of the rafter tails, and then installing 1x boards perpendicular to the rafter tails spaced to allow ventilation. I've drawn my idea (not to scale.)

The rafters have v-cut blocking at the exterior wall. The v-cuts are the limiting factor for the ventilation area, so the soffits need to be fairly open to airflow.

I have a couple questions:

A: Does this seem like a good idea?

In General questions | Asked By John Ranson | Jan 13 17
10 Answers

Please pick my plan apart- better now than after it's built.

If anyone wants to provide input it would be greatly appreciated.

This is to be our retirement home. Energy efficient, double stud walls, the walkout is to the south. Masonry wood stove in living room.

Please note the three level breezeway. I struggled with window sizing and ended up with a lot of different sizes based on room use not exterior balance. Not good?

The South First floor overhang is too small. My designer/draftsman changed it to give upstairs windows some room. That will change and go to 9' ceilings in upstairs if needed.


In Plans Review | Asked By jim sweazey | Jan 13 17
6 Answers

Triple pane vs. double pane in Phoenix

Im at the point where I have to narrow down my material choices for my new home build. Im in PHX, living in a home built like this : http://www.greenbuildingadvisor.com/blogs/dept/qa-spotlight/why-are-hous... . And its driving me nuts having to pay my electric bill every summer ($500 a month and thats with solar!!). Currently I have spec'd Intus triple pane windows (Vinyl Arcade line, not the higher end Eforte) for their U Factor (high 0.10's). I'm the opposite of most as I am trying to block the introduction of heat through thermal transfer not the loss of it.

In Energy efficiency and durability | Asked By Jeffrey Savage | Jan 12 17
12 Answers

Mini crawl space

I have decided to convert a piece of my timber frame barn into living space on my new home.( the barn is there) what I would like to do is elevate a 2x 8 floor above the existing slab. This would hanger onto the existing perimeter grade beam that sits on top of the concrete stem walls. I would set the floor 1.5" higher than the grade beam to create a thermal break with a narrow ripping of eps. So I would end up with about 10 inches beneath the floor assembly.

In Energy efficiency and durability | Asked By scott mangold | Jan 7 17
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