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1 Answer

Insulating block walls

I am currently remodeling an old gas station. The exterior walls are cinder block. The building is 26 feet by 48 feet with 12 foot high walls. One third of the building (26 feel by 16 feet) will be used for a meeting area and have two bathrooms. All of these walls have been framed up with dimensional lumber. The perimeter walls of this space have been insulated and a vapor barrier applied followed by drywall. The remainder of the building will be used as a heated storage area with no interior insulation. The exterior of the building is to have LP smart siding.

Asked By man of steele | Mar 20 18
5 Answers

Brick Ledge help with Rigid Foam Over CMU


I am doing a custom new construction home and am trying to get some economical ideas on how to best provide a brick ledge when I add up to 4" of exterior rigid foam in zone 5.

Currently, the plan is to have a 10 inch CMU basement, that then steps down to 6 inch CMU for 2x6 stud walls, the other 4 inches is to be used for brick that starts just below grade. The brick travels through the first floor. The second floor will be vinyl double lap siding.

Asked By Wayne321 | Mar 20 18
5 Answers

ERV with HEPA filtration options

Hi Everyone,

Been a lurker here and I have a question and looking for advice.

Im building a new home, my previous home burned down. Im in Southern California, climate zone 3b, and my house will be pretty air tight, built with sip panels and using mini splits for heating and cooling. House is around 4300 sqft, I talked with some people and they recommended 3 Panasonic FV-04VE1 ERV units for ventilation throughout because of the lack of attic spaces and expenses.

Asked By m4tr1x | Mar 20 18
0 Answers

Ideal window depth to minimize window perimeter thermal bridging through frame

I am replacing the windows and redoing building envelope in my 30 year old house. Currently have 2x6 framed wall, covered with 5/8 tentest type fibreboard and then wood siding. Windows are original 30 year old solid wood. I am replacing windows with the following: Basic flush mount vinyl high efficiency windows, 4 5/8 thick with interior jamb slot for interior trim to be added to.

Asked By user-7038920 | Mar 21 18
5 Answers

Open cell spray foam under roof deck

A couple years ago we converted our vented attic to an unvented/conditioned attic with open cell spray foam applied under the plywood roof deck. We even installed an HVAC vent in the attic to keep the RH in the attic similar to the rest of the house. So far everything seems fine but I've recently read about issues with open cell under roof decks, including one article on this website. I live in climate zone 4, asphalt roof over plywood deck. Should I be concerned about having a wet roof deck?

Asked By Michael Mohr | Feb 7 17
4 Answers

Outdoor mini split condenser unit in an insulated ventilated box indoors?

I need to cool (summer) and heat (winter) one room which is total 16.7 x 12.2 x 8.5 feet (1731 cubicfeet) (5.10m x 3.70m x 2.6m). I would need a unit between 2 or 3 tons.

Unfortunately I am not able to install the outside condenser unit outside of the building. That is the reason why I need expert advice.

Asked By purpleAnt | Mar 20 18
2 Answers

What is the minimum depth a water line must be in zone 6 and pure medium to course sand?

I know there must be code requirements but there must also be some scientific way to know at what minimum depths a well water line will not freeze, because I'm thinking the soil composition would be a significant factor. I am in zone 6 in Traverse City, Michigan in pure medium to course sand and on a hill 35 feet above a small lake. The sand is very dry.

Also, can I use Pex underground from the well to the house? I have heard that it is somewhat flexible and resistant to cracking or bursting if the water freezes.

Asked By user-6992381 | Mar 20 18
14 Answers

To Spray foam or not?

I am trying to decide whether to spray foam my house which is currently down to the studs. I am in climate zone 2 so it is hot and humid most of the year. The house currently was built to have a vented attic. The house is about 3,000 square feet and is one story. I have a asphalt roof shingles that I had installed last summer. My HVAC equipment and water heater are in a mechanical room separated from the living space by walls and with a louvered door to the outside.

Asked By Kasey Doggett | Mar 18 18
4 Answers

slumping of siding from nailing through rigid foam

Thanks for any assistance you can provide.

I am wanting to add additional insulation on the outside of our home. We are in zone 6. Our current walls are 2x6, 24 inch on center with 6 inches of fiberglass insulation, 7/16th OSB with tyvek. We have lived with cedar siding for 30 years and are now wanting to remove the siding and windows. Replace the windows and us LP siding.

Asked By user-7005676 | Mar 20 18
13 Answers

DIY air sealing equipment

Other than a blower door, which is impractical for this application, what specifc products do you recommend for a homeowner interested in air sealing? What is the best homeowner-grade thermal imager (if there is one), smoke pencil, etc?

Our moderate retrofit reduced a very leaky, large house from 7330cfm to approx 5000cfm, and I want to keep going.

Thank you.

Asked By Emerson | Mar 13 18
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