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0 Answers

Water between the bottom of the window and rough opening?

Building a home in zone 4A and we done with framing and setting the windows and house wrap. The windows have been flashed and the house wrap is taped to the window on all 4 sides.

This morning, the builder needed to take a window out, and when he did he noticed a lot of water under the window between the window and the rough opening. He said it was a lot of water.

Asked By Clay Whitenack | Aug 25 16
56 Answers

Two condensation questions

I have a newly foamed attic with open-cell foam (average 8 inches or so with rafters covered) and a brand new AC unit with furnace. I had thought that lowering the temperature of the attic would take away the need for insulation on the condensate drain line, but it is still sweating. The upstairs temperature is in the 75 degree range in the Attic is in the 81 degree range, but the Attic humidity has gone from being in the thirties or forties when it was a vented attic to being about 70% now, so I guess the dew point is still high enough to necessitate insulating the drain line.

Asked By John Sexton | Aug 7 16
27 Answers

Ice damming — Low-slope roof — Resolvable or hopeless?

[ SUMMARY ]

I own an older home in Ontario Canada that may have been built between the 1920s to 1950s. It originally had knob & tube wiring.

Each winter I have to deal with ice damming along 2 sides of the roof, no where else. The areas in question are a Low-Slope roof (3/12 pitch, east & west side of the ridge) and a Cathedral style roof (8/12 pitch -- inside the home there is a sloping ceiling that is covered by drywall). See a photo of the home: http://imgur.com/sXUzfzG.

Asked By Jake Rabe | Aug 19 16
5 Answers

What to do about stairs and doors during basement energy retrofit?

Good evening,

Asked By adam stanton | Aug 24 16
1 Answer

Adding a soffit overhang to gables of an attached 4-season room

I'm currently having the roof of my attached 4-season room replaced. The roof leaked in heavy rain and there was a measly 1" of XPS on the inside of the roof. The new roof will have 6" of polyiso on top of the timber frame rafters.

Asked By William Sherman | Aug 25 16
8 Answers

Help me understand static pressure in ducted minisplit systems

Hi all,

Tried to piggyback a comment on this thread (http://www.greenbuildingadvisor.com/comment/reply/55726), but I guess the thread is too old and my comment was marked as spam.

I am planning a ducted mini split for the 2nd floor of our home. I have run manual J calculations and find that a Fujitsu 9RLFCD will fit the heat/cool load, assuming I can distribute the BTUs to all the rooms.

Asked By Clay Whitenack | Aug 16 16
15 Answers

Solar hot air preheat for HRV/ERV

Has anyone seen a successful approach to using a solar hot air collector to preheat the intake air for an HRV / ERV?

It would be fairly simple to bypass the collector when preheat wasn't desirable.

One major concern is regulating temperature so excessive heat doesn't compromise the HRV / ERV.

It seems like it could be an ideal way to temper incoming air on cold, clear Colorado days (climate zone 6B), and get a little extra solar gain.

Asked By Pat Kiernan | Aug 17 16
8 Answers

Polyiso sandwich with synthetic underlayment

I'm located in Central Texas (China Spring, TX) and am building a house with my wife. The house was originally started by the previous owners and we are replacing and redoing quite a bit of it at the start. We are doing the majority of the work ourselves (taking forever) and we are at the point of finishing the roofing

Asked By Jacob Cox | Aug 24 16
1 Answer

ERV and humidity

This is more for my own curiosity.

I've read that ERV's are generally suggested for warm humid climates and I've also read they can cause humidity levels to rise within a home. My understanding is that with an ERV some moisture is transferred from the stream that contains higher levels of moisture to the stream that contains less. Does the system medium look to balance the amount of humidity between both streams?

Example, Stream A is at 40% RH , Stream B is at 20% RH, ~10% is transferred from A to B where both end up at ~30% RH)

Asked By Chris M | Aug 25 16
3 Answers

Wall detail for exterior foam and ... (wait for it) ... SHINGLES

We're in the process of building a home in MA and committed to external foam on walls and roofs

There's a ton of great detail here on exterior foam and I've followed / read it and Martin's other posts on rainscreens.
We're still struggling with the best practical assembly for traditional shingles rather than clapboard.

There are the 3D mesh rainscreens that Martin suggests in his "All About Rainscreens" article, but if those are used, how do you provide a nailbase for the shingles? If thye are used is thee sheathing put at the outside?

Asked By Edward Cambridge | Aug 24 16
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