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0 Answers

How does efficiency in a mini-split vary over various operating levels?

It is my understanding that a SEER rating is determined by simulating the operation of a particular make/model air conditioner over a hypothetical season, presumably assuming various temperature and humidity levels throughout the year.

Asked By david jensen | May 3 16
18 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
6 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
3 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
9 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
1 Answer

Luxury vinyl tile / plank

We need to select our flooring. Our plan had been to use wood laminate, but several people we know have recommended that we look into luxury vinyl. We hear that it looks very similar to wood or tile, is much easier to care for than wood, and is much cheaper than tile. Do people on this forum have experience with and/or opinions about this type of flooring?

Asked By Reid Baldwin | May 3 16
1 Answer

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.

the grade has been leveled and sewer drains in trenches and backfilled
then there is a 4-6" layer of compacted gravel and we plan on using a 15mil taped vapor barrier and 2" of taped 60psi XPS on top of that.

for a thermal break we are using 2" 25psi XPS that extends 10" below the slab

there will be radiant installed throughout the building and we are in

my main question is:

Asked By Big Ern | May 2 16
1 Answer

Drain penetrations in a 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.

the assembly we are planning on was to cut a hole in the vapor barrier and attatch to the cast iron pipe with tape, then cut a hole in the insulation around the pipe and fill with spray foam and finally to wrap the segment of the pipe that would be in contact with the concrete with thin foam insulation..

Asked By Big Ern | May 2 16
5 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
9 Answers

Pond pebbles instead of crushed gravel for the driveway - what to do?

Hello,
Our general contractor received a wrong kind of gravel for our big driveway install. We have 1500 sf to build and 1/2 of it is a concrete driveway and 1/2 permeable pavers. We have 2/3 of the total rock needed already on site. And that rock is pond pebble instead of limestone gravel that would have properly compacted under the driveway. Supposedly this cannot be returned. What are we to do?

Asked By Lucyna de Barbaro | Apr 30 16
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