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5 Answers

Photovoltaics: String vs. Microinverters

CZ-4. Southern Indiana. New Construction Ranch. Garage Roof faces 30 deg west of south (210 deg). NO shading from trees now or in future. About 36 Grid-Tied Panels. No battery back-up. A purchase arrangement, not a lease type transaction. Three major installers in the metropolitan Louisville, KY market.

Two competing PV installers. One for Microinverters ; one for Strings with single inverter/optimizer.

Asked By Ted Cummings | Apr 30 16
4 Answers

Economical, Long-Lasting, Flexible Sealant

CZ-4. Net Zero Energy Home. New Construction Ranch . Concrete Slab-On-Grade. Planning for 0.1ACH50. Using Huber Zip-R panels with (1"PolyIso laminated to the OSB).

Asked By Ted Cummings | May 2 16
0 Answers

Drain Penetrations in Slab on grade

Hi, we are pouring a 5" floating slab on grade with several cast iron drains penetrating through the slab.

the drain lines run in the compacted fill below the 4-6" compacted gravel, 6mil vapor barrier, 2" tongue and groove xps and the 5" 4000psi pour with 1/2 radiant pex throughout.

Asked By Big Ern | May 2 16
10 Answers

Insulation and air conditioning

After reading this blog I feel much more informed in a general sense about my insulation and heating/cooling needs, but I am still trying to figure out what the return on investment would be for certain applications in my condo.

Asked By Kevin Gabbard | May 1 16
7 Answers

Roofing and insulation on old house

I have an 1850s farmhouse I'm renovating. To insure good insulation, I had the attic rafters spray foamed with closed cell foam about four inches deep.

I'm trying to plan for an eventual re-roofing, and I wanted to know if there are any best practices I should keep in mind at that stage for eleminating any issues that might arise from the spray foaming. The old roof has a few layers of shingles on it.

Is there a recommended roofing type for this situation? Any ventilation issues I can helpfully prevent moving forward?

Thanks,

Ilmari

Asked By Ilmari Polojarvi | Apr 30 16
17 Answers

New slab with radiant heat

As part of our remodel north of San Francisco (ZIP code 94941), we are converting about 700SF of our lower level into living space. The existing slab has been removed we excavated a few additional inches to increase our ceiling height, and we are getting ready to put back a new 5" slab, in which we will also add radiant heat tied to the rebar.

Asked By Torsten Budesheim | Apr 22 16
3 Answers

Continuous insulation under slab

Hi all,
I am looking for some advise on the design of our thickened slab for a "pretty good house" in Kenora, Ontario (climate zone 7).
The house will be 32' x 24' with a loft. We are planning for 6" of rigid foam under the heated slab. Our designer and engineer are adament that the rigid cannot be placed under the footings and under the post. They are telling me this is against the Ontario Building Code and that the engineer will not put his stamp on it.
I am wondering if anyone else has come across this in Ontario?
Thanks.

Asked By Adam Smerchanski | May 2 16
0 Answers

A temporary situation for new people registering on GBA

As our I.T. team tries to find a good way to block Chinese companies which have been flooding our site with spam, we need to temporarily stop accepting new registrations for the GBA site. (I'm talking about the free registration that is necessary before you can post a question or post a comment.)

We anticipate that this situation will only last for a few days. Once we get a handle on a way to fix the spam problem, the site will once again accept new registrations.

Anyone who wants to become a GBA subscriber can still subscribe at any time.

Asked By Martin Holladay, GBA Advisor | May 2 16
2 Answers

Integrating rainwater collection system into house water faucets?

Hi all,

Building a new house and at some point I would like to have a rainwater collection system. This system would route the gutter downspouts into an underground tank and then have a pump to distribute the water around the yard.

Thinking about how to distribute the water around the yard, I had the idea to connect the tank to my house water hydrants (house bibs, outdoor water hydrants, etc.).

Asked By Clay Whitenack | May 2 16
1 Answer

Paint as an Air Barrier

CZ-4. Net Zero Energy Slab-On-Grade Ranch. Planning for 0.1ACH50. Huber Zip-R sheathing.

Asked By Ted Cummings | May 2 16
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