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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
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
3 Answers

Housewrap on the gable (non-living attic walls) or not?

My framer will not put Tyvek, house wrap on an gable wall where there is no conditioned air. (non living space above the house. I have found proper attic sealing, venting, insolated articles to back this and to dispute it. Please advise.

In Green building techniques | Asked By william trent | Jul 26 15
2 Answers

Another solar pumping question

Hey there,
I would like to use solar power to pump around 10.000 L of water/day from a well into a reservoir that I could use for gravity fed irrigation via a drip system. Please give me your thoughts on this, I would like to know if it's doable. I'm a newbie so please bare with me if I ask something outrageous
The specs on the pump:
At 45 volts DC the peak efficiency point is 18 GPM at 45 feet of head..
Max Current: 8.5 Amps
Max Power: 380 Watts
My question is:
Is it possible to run this pump directly from solar panels with an LCB? Would 2 x 250W panels wired in series do the job?

In Energy efficiency and durability | Asked By lee alice | Jul 24 15
5 Answers

Kerdi shower system vs. concrete board

Builder recommends the Kerdi shower system applied over the dry wall and that's what the local tile people use too.

One of the bids from an out of town tiler, who works on high ends houses, recommended cement board instead of dry wall?

This is in regards to the shower area in the bathrooms.

Please advice

Thanks

In General questions | Asked By Yasir Khan | Jul 25 15
4 Answers

Best practice/advice- Three insulation assemblies

I need guidance/advice on insulating three separate assemblies as I finish the space on the 2nd floor of our 1952 Cape Cod.

The space: Total 2nd floor square footage equals 960- all conditioned space
No dormers on the front, single shed dormer spans nearly the entire backside of the house.
Williamsburg VA- Climate Zone 4A- more hot & humid than you might imagine.

Here is what we are starting with:

1. Exterior wall on either end (facing North & South) is constructed as follows- Brick, 1" airspace, #15 felt, 1/2" insulating (asbestos?) sheathing, 2x4 studs

In Energy efficiency and durability | Asked By Chris Kolloff | Jul 24 15
21 Answers

Will minisplits work in all floor plans?

I'm researching the details of building a new house in central KY, zone 4a. This will be the house that lasts for the rest of our lives (hopefully 50+ more years). I had assumed that GSHP were the "no-brainer" HVAC choice, but from the looks of things, it isn't that simple. I've been reading some amazing things about the potential of mini split systems.

In General questions | Asked By Clay Whitenack | Jul 20 15
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