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0 Answers

Exterior rigid foam and re-siding project...

I'm seeking input and opinion. I'm looking to re-side with the dread vinyl (need the low maintenance for my two story house). My 40 year old post and bean house has interior sheetrock, 3.5" of fiberglass batt insulation with kraft paper, rough cut full 2x4 studs on 24" centers, plywood sheathing (I think 5/8"), paper (a mix of Tyvek and felt), and cedar shingles. Shingles and paper will of course be removed, sheathing inspected in the process. I'm in zone 6.

Asked By Howard Gentler | May 2 16
6 Answers

High humidity in spray foam attic

Hello all,

Last fall I had my attic spray foamed. Warm temperatures have arrived and I am experiencing higher than anticipated temperatures and humidity in my attic.

I have 3 main questions (pertinent details follow):

1. Is a semi-conditioned attic RH in the 60 - 70% range cause for concern?
2. Should my attic be 10+ degrees warmer than the interior? It will get much warmer here in the coming months and I am worried that the attic temperature difference will grow.

Asked By Nic Smith | Apr 30 16
0 Answers

Slab Thermal Break at vehicle roll gate

as I mentioned in a previous post we are putting in a new floating slab on grade in a warehouse building.

Asked By Big Ern | May 2 16
11 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
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
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
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