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6 Answers

Trapped moisture on SIP roof

I knew SIPs were the Achilles heel of my 100% engineered house design, But because of inattention to detail, heavy rains at a critical time of my house build pushed water underneath the PVC membrane (applied on mechanically fastened DensDeck) onto my SIP. It happened the night before the adjacent wall could be spray foamed to properly seal off the membrane. Unfortunately, the spraying was later done to the walls and the underside of the SIPs without knowing there was water present.

Asked By Edward Mallett | Jun 29 15
52 Answers

Attic hot after closed cell spray

Finished attic with 4 foot knee wall , duct located in knee wall to support 2 floor,extremely hot, BASF spray tite 2 inches with spray foam wraped around rafter in knee wall but with Sheetrock on ceiling just 2 in foam In cavity . Suggestions to handle heat issue. Richmond Virginia all attic seal very well thinking heat coming from rafters under Sheetrock. Thermal convection coming from rafters. Worked done in the winter, crawl space also done, house built 1994 colonial 2 story with garage with room above with dormer. Also in crawl space does it really need supply vent and return vent

Asked By Mark hippchen | Jun 27 15
42 Answers

Spaceloft my only option?

Needing to get all the R value I can get in a limited space. From the cob webs you can see that this is an old house. Recently installed Cedar shakes with felt underneath over the 2x4 studs or mini rafters...
I think they call this a skip sheathing install of the cedar roof?
So, 3.5" is all we have but we'd like to get to an R50 or thereabouts in our upgrade of this 1925 built home in Climate zone 4C.
Spaceloft seems the only option. With an R10 per inch. It comes in 10 cm thickness, 0.4".

Asked By Jan Verschuren | May 29 15
1 Answer

Nebraska — unvented attic with high humidity

Last year after a severe hailstorm the attic insulation and the entire roof deck of my 1600 sqft ranch style home in Fort Calhoun, NE was replaced. With the replacement we upgraded the insulation to Open Cell Icynene spray foam on roof decking. The spray foam is at least 6-8 inches on the roof, and covers the sidewalls, soffits, and attached garage ceiling. This completely closes in the attic to the thermal envelope of the house. I've been monitoring the relative humidity levels of the house for the last year.

Asked By Nick Schuler | Jun 28 15
70 Answers

Geothermal nightmare

We truly hope you can help us. We had a geo-thermal closed loop system (into the river) put in and it went online March 2012. WaterFurnace Super DeHeater, 4 Multi-Aqua mini-splits (included for AC) and an air-handler (included for AC). 3200 sq ft home with baseboard and in-floor radiant heating. $34,000 and we have had nothing but problems.

Asked By Colleen Nicholson | May 30 13
5 Answers

Flush-mount exterior electrical boxes in board & batten with rigid foam and rainscreen?

Good evening all,
I'm still working thru issues involving board and batten over strapping and rigid foam. Now I'm looking into the exterior electrical boxes (for outlets and for lights).
I'd like the boxes to be flush-mounted, with the "rain screen" (do we still call it a rain screen if the strapping is horizontal?) space serving as a conduit chase. That would minimize penetrations of the insulation and WRB- while avoiding surface-mounted conduit.

Asked By Ben Rush | Jun 25 15
3 Answers

Where's the smell coming from?

A musty, mildew smell emanates from 2 bedroom closets in the front of our single story 13± year old house every time it rains since we bought it 2 years ago (and before us no doubt)...but nowhere else in the house.

Asked By Sallye Esch | Jun 23 15
98 Answers

Unvented slanted roof with radiant cooling and NO polyurethane in 4C

We are in Everett WA, north of Seattle, right on the coast, zone 4C. I hope that our location will save us...
We have a low sloping steel, west facing roof. Double, 30 weight felt paper underneath to dampen rain noise. I presume 1/2" plywood sheathing. 2x12" rafters, 11" true depth.
We will install WarmBoard R (13/16" thick OSB with aluminum tracks) underneath the rafters for summer cooling and supplemental heating in winter.

Asked By Jan Verschuren | Mar 11 15
4 Answers

Intus installation

I am considering Intus windows for a project happening soon due to their great U-value and high SHGC numbers. One thing I'm hung up on is how to install them with a 3/4" strapping rainscreen and exterior trim. The supplier said the window is installed at the sheathing layer then the rainscreen and trim are applied over that. That method seems to flash it well at the top but what about the water running down the face of the windows. There are also weep holes that need to stay open on the bottom making sill trim tricky.

Asked By Caleb Creaven | Jun 3 15
1 Answer

Need input: House location on site, soil compaction, grade changes, retaining wall

I would like your input regarding the house location on my site plan (I am the owner).

My considerations:

1) Southern exposure vs. street angle so we oriented 15 degree from true south. I am happy about this decision and I think the landscape architect is capable to make the landscape work with this orientation.

2) Main unresolved challenge:

Asked By Ying Li | Jun 7 15
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