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15 Answers

Proper way to detail bottom edge of rigid foam next to sill plate

I am going to be installing 2" of rigid foam over my OSB sheathing soon and I have two concerns. The current one is what is the most DIY friendly method to protect that bottom edge of foam that is under the siding, but next to the ground near the sill plate? I want to prevent bugs of course, but also keep moisture out too. I see videos of pros using aluminum flashing but they have fancy breaks and coils of it. Is there a DIY alternative? Local supply store would be Menards if there is a certain product to suggest. Thanks.

In Green products and materials | Asked By Nicholas C | Jul 25 15
4 Answers

How much more efficiently does a ductless mini-split perform below peak demand?

My Manual J load calculation for my the 960 sf house I'm building in central Arizona shows a heating load of 13,535 BTU and a cooling load of 11,860 BTU.

I'm debating between two ductless mini-splits:
Panasonic E12NKUA with inverter: 12,000 BTU Cooling 13,800 BTU Heating, 20 SEER 10.6 HSPF
Panasonic E18NKUA with inverter: 17,100 BTU Cooling 20,400 BTU Heating, 18 SEER 8.5 HSPF

In Mechanicals | Asked By Jeff Cooper | Jul 27 15
2 Answers

Flat roof insulation

Here is the Chicago area.
If I can't ventilate the flat roof, then what happens?
what if I am using the fiber insulation and radiant barrier together..?

In Energy efficiency and durability | Asked By Mansig Yoon | Jul 26 15
5 Answers

Closed-cell foam in a 65-year-old Cape Cod roof?

We recently removed all of the vinyl siding and homasote from our cape. We installed R15 fiberglass in the walls - there was not insulation previous to this, just homasote. In addition, we replaced all of the windows with double glazed argon gas filled low E windows.

In Energy efficiency and durability | Asked By Michael Boice | Jul 24 15
17 Answers

How do I get and keep air out of my geothermal loop?

We have a "closed loop" geothermal heating and cooling system. 97 wells 300 ft. deep. 4 story building. 36 water source heat pumps. 72 electric water pumps. 219 ball valves.
There is no way at the high point (attic over 4 story) to release air and no easy way to add water to displace the air. The contractor keeps trying with their big pump and tank trailers to purge the system by driving the air bubbles out through the basement. No surprise to me, having observed the bubbles in my bathtub travelling upward, this approach keeps failing.

In Mechanicals | Asked By Todd Conradson | Jul 1 15
1 Answer

Questions about Earthcraft

We are looking at Earthcraft as a green building certification process.

If you have experience with Earthcraft your comments, and suggestions will be appreciated.

We offer a guaranteed $100 electric bill already up to 2000 heated square feet, so we're already pretty good at energy efficiency.

We're hoping to learn the pros, cons, and suggestions of others before we engage with Earthcraft.

Thanks for your time.

Rod

In Green building techniques | Asked By Rod Moelleer | Jul 26 15
4 Answers

Using I-joists for Larsen truss web and building wrap for blown cellulose

I am building a 2 story house on the Kenai Peninsula of Alaska and I am planning on installing a Larsen Truss on the exterior of a 2 story 2x6 framed house sheathed with plywood. As an owner builder who is trying to balance time efficiency vs cost efficiency I am trying to think of ways to speed up and ease construction of the Larsen truss. I recently thought of using I joists for the Web. It seems like this could speed up construction significantly allowing for the building of the truss on the ground prior to installation.

In Green building techniques | Asked By Chris Walker | Jul 26 15
8 Answers

General contractor and his responsibilites

Guys,

Building a house and now trying to dig myself out of the hole created by my general contractor.

The house is a custom 9600 square feet (9 ceilings basement/ground, 8' second floor with 3 trey ceilings), a covered patio (16' deep x 70" wide) with 5 car garage (1900 sq-ft with13' ceilings)

In General questions | Asked By beenash khan | Jul 25 15
34 Answers

It's 2015 and they still build like this...

Brand new build going up in Phoenix, AZ. What you see is completely 100% framed and ready for stucco. The missing OSB sheathing is done on purpose. They do "open framing" and only use sheathing where required. The rest is open 2x4 framing.

They will stuff R-13 batts within the 2x4 walls, staple on some building paper and then put 1" of rigid EPS on the outside and use conventional stucco to finish it off.

A recent blower door test on a home like this showed 15 air changes per hour.

ALL of the duct work and air handlers are installed in the 150F unconditioned attic.

In Energy efficiency and durability | Asked By Peter L | Jul 1 15
2 Answers

Wet cellulose blown-in insulation — is mold a concern?

I am building a house in Kansas City, MO. The brick contractor did not flash the windows properly and the cellulose blown in insulation has taken on some water. Moisture readings in the walls are 25%-35% with a normal of 15%. Windows are being flashed properly to prevent future water leaks. Will there be a mold problem with the cellulose blown in insulation or does all of the wet areas need to be removed and reinsulated with dry insulation?

In Green products and materials | Asked By Stevee Busser | Jul 25 15
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