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5 Answers

Thermal bridging solutions when closed-cell foam is used?

What is the best way to handle the thermal bridging of the wood framing of my house -- recognizing that some closed cell foam is specified for the wall cavities? We are constructing a house in climate zone 5 with 2x6 studs using the "hybrid wall assembly" as defined by Joe Lstiburek in his article "Hybrid Attics and Hybrid Walls." I have seen no comments about managing thermal bridging using this type of wall system.

Asked By Judy5 | Jun 21 18
1 Answer

Unvented roof — vaulted ceilings — moisture, rot, etc.

Im hoping someone can steer me in the right direction for an issue Im having with my current roof.

As best I can describe here is the situation

Full home remodel completed in 2015 including 2nd story addition and brand new roof.
Home is in Southern California about a mile or so from the beach
Vaulted Ceilings exist in every bedroom, however the problem seems to be localized to one side of the house where there is not attic space, no venting.
Canned lights exist in each room, they are just standard cans IE they are NOT fully enclosed/sealed

Asked By Meyersrl | Jun 22 18
2 Answers

Best practices for fastening lath / 3-coat stucco over rigid foam

There seems to be some debate over how to anchor 3-coat stucco over rigid foam while maintaining <1/64 deflection to avoid cracking. It seems that for:

<=1" Foam, Standard Wide Crown 2" Staples into Studs are Adequate
2" Foam, Lathe & Plaster Washers and 4" #10 Screws every 6"
4" Foam, Furring strips or add additional OSB/CDX Sheathing over Foam and staple lath

My question is,

1. What would you all recommend for 1-1/2" Foam (R-Max Polyiso)?

2. Would there be any advantage to a hybridized system of staples and screws/washers - i.e. screws every 12", staples every 4"

Asked By Zane Bridgers | Jun 21 18
24 Answers

Dirty electric from minisplit ductless heat and air conditioning

I saw a u tube video on a Fujitsu mini split system air/heat...where a building biologist specialist was testing a persons house for dirty energy. He found from the box on the outside of the house had very high amount of electro magnetic interference... and determined that it came from a Fujitsu Mini Split system... he used filters to try to eliminate the energy...which worked for everything but the Fujitsu System. He said the spikes were the same type that causes occular melanoma cancer.

Asked By Arleendv | May 30 18
7 Answers

Vapor retarder for exterior walls Zone 4

Good afternoon,

The insulation guys installed un-faced batts in the exterior walls in my house in Nashville Tn. Should I install a smart vapor barrier (certainteed membrain) over the insulation?

- The house was built in 1964 with thermo ply sheathing. As seen in the image the sheathing is very
leaky. I have done my best at sealing the sheathing with caulking and great stuff foam.

Thanks! ~Bob

Asked By Bob Harshman | Jun 21 18
13 Answers

Need some unbiased input on these 2 proposals

So I've gotten 2 proposals from different geothermal contractors and I just wanted some unbiased opinions on the work and equipment. Both proposals came in at around 40k so there's no huge up front cost benefit from one over the other.

Company A is proposing a 3 ton Hydron YT Series 2 Stage heat pump
Full Load: Cooling 41,200 BTUs at 20.9 EER, Heating 29,100 BTUs at 4.5 COP
Part Load: Cooling 31,500 BTUs at 31.3 EER, Heating 23,300 BTUs at 5.1 COP

Company B has 2 options, a Waterfurnace Series 5 single stage model 030 or double stage model 038

Asked By milhouse21386 | Jun 20 18
15 Answers

Do I need an HRV/ERV for a house built in 1947?

I have a three-bedroom house, one bathroom, in Worcester, Massachusetts. It was built in 1947, and measures 1,100 s.f.

After purchasing it, I decided to upgrade the insulation in the walls and in the attic and air seal the home, and install new windows. All which was done through the Mass Save program. After completing, all the energy bills went down.

But the problem now is the house has high humidity and seems to be too tight and cause hard breathing. I have noticed mold that I did not have before. Also get headaches more often than I used to.

Asked By Will82 | Jun 14 18
17 Answers

Re-sealing failing SIP roof panels

We have a 7 year old SIP panel over a timber-frame home. We have noticed for several years significant condensation of moisture to the point of dripping from light fixtures and ceiling fans located in the peaks during hot summer days. Roof is a stone-coated metal shingle panel over Grace Tru-flex underlayment.

Asked By Passagyrs | Jun 19 18
3 Answers

Single minisplit for AC?

Looking for feedback on adding AC to a ~1600 sq ft ranch in central NJ. Current setup is a window unit in the bedroom and a 1980s 220v beast of a wall unit in the dining room. Together they do all right in those worst weeks but for the most part we've just been toughing it out. I'm on a well shaded lot and the house stays reasonably cool during the summer, but also a bit damp. So hoping to dehumidify with the AC and of course cool the place down during the hottest weeks of the year.

Asked By Jeffesonm | Jun 20 18
11 Answers

Air Barrier Location

I'm in the process of beginning our new home in the next few weeks. We're located up in Newfoundland, Canada, just around St. John's. We're planning on incorporating a double stud wall to increase the R-value of the home. The plan is, from outside to in, : R8 Comfortboard, Tyvek, Plywood,, 2x6 wall with fiberglass batt, 6mm poly, and 2x4 wall with fiberglass batt which will contain all of the electrical and plumbing.

Asked By Dan C | Aug 6 17
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