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21 Answers

Another crawl space in the Northwest

Hello all, I have a 1150 sq ft rambler house in Fall City, Washington (near Seattle), zone marine 4c. I am currently in the process of redoing the crawl space. I have pulled the damaged and rodent infested insulation down, and removed the town vapor barrier. It seems I had some rodents that were digging past the foundation and getting into the crawlspace, ruining everything.

Asked By David Meyer | Nov 28 16
1 Answer

How can homeowner find contractor to install rigid foam on top of roof sheathing?

To everyone, but especially anyone in the Chicago area:

Asked By Rebekah Haworth | Dec 8 16
3 Answers

Double interior rock wool

Working on plans for my next home. After lots of research on here and others I am considering the following wall assembly. From the exterior... wood siding, tar paper, 1/2" plywood with taped joints, 2x4 ,16 on center wall stud with roxul, uniterupted layer of 1 1/2" comfort board, layer of a variable perm vapor barrier (taped seams and such), then a layer of 2x3 installed 2 ft. on center as battens for electrical with shallow boxes , second layer of comfort board fit between the battens, drywall finish. I am in zone 5 in northern ct.

Asked By scott mangold | Dec 8 16
1 Answer

Airflow around mini split compressor

Hi, the installer for my Fujitsu 15RLS3 installed the lineset in such a way that I think it restricts airflow behind the compressor quite a bit. See the attached photo. They wrapped the lines in a circle a bunch of times between the back of the unit and the wall to deal with the fact that the outdoor compressor is less than 15 feet from the indoor unit. In any case, do you think this restricted airflow affects efficiency or longevity of the system and I should ask them to put the lines elsewhere ? Is this way of installing the system even in line with manufacturers instructions?

Asked By matthias paustian | Dec 8 16
3 Answers

We plan to use Obdyke Hydrogap between the Hardie board siding and the Zip wall

We plan to use Obdyke Hydrogap between the Hardie board siding and the Zip wall. Will that be an adequate drainage plane? Or are furring strips also needed?

Asked By Courtney McCracken | Dec 5 16
3 Answers

Optimum air gap for skylight

Context: a 14x7x6' tinyhouse with 4"-thick polyiso insulation on all surfaces except the windows, which, for reasons that aren't relevant here, must be on the roof.

Several hours of research shows that the optimum air gap for a typical double-glazed window ranges between 13-30mm depending on whom you ask. Charts show that U-value tends to bottom out at around 13mm and slowly climbs up from there. From this research I've gleaned hints that the glazing material and the angle the window is mounted at are factors, but I've been unable to find out how they matter, so I turn to the Community.

Asked By Geva edhrven | Dec 8 16
3 Answers

Exterior Rigid Foam Under Sheathing?

In my local area there is a green building consultant that recommends a CI panel which is basically EPS foam glued to OSB. The way this is installed would be the OSB to the exterior. Almost every house I see with exterior rigid foam in my online wonderings is covered with blue and pink XPS, the OSB sheathing is nailed directly to the studs and is completely covered with the rigid foam. This leads me to the following questions:

- Is anyone familiar with these kind of CI panels?

Asked By Joshua Greisen | Dec 8 16
7 Answers

What is the relationship between air source heat pump and indoor heat pump water heater?

I am sure this has been analyzed here before, but I want to check my reasoning. A criticism of heat pump water heaters is that they cannibalize the home heat source and so during the heating season perform exactly as electric water heater efficiency. However if the heat is provided at COP 3 from an external air source mini split, then am I correct that the heat that is being "borrowed" by the heat pump water heater is also COP 3 and so year round the heat pump water heater functions at COP 3 or better?

Asked By ven sonata | Dec 5 16
5 Answers

Converting a 1830 House to a Super Insulated House

I am diving into the insulation in my 1830 Farm House, 1500 sqft, which is located in upstate NY. I am looking to retro the house into a tightly insulated house that will ultimately heat off of electric heat or heat pump mini splits. I just had 10kw Solar system to create the electricity for the heat. The solar system was designed to cover 110% of our projected electrical consumption with a mini split system running. My goal is an 1830 super insulated house.

Asked By Larry Broderick | Dec 7 16
1 Answer

Moisture where ceiling and walls meet on exterior walls

Hi I recently read a article on here talking about my exact problem and that someone had did a study to fix it , I was having trouble completely understanding if the three things they did worked at all? One was insatlling 6 inch insulated crown moulding in the interior of the house. I can't find it for sale anywhere and I read another article that some guy used 6 inch mdf crown moulding and drilled holes in it and sprayed great stuff into it but he never said if that fixed his issue or not.

Asked By Patrick Conry | Dec 8 16
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