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18 Answers

Enclosed room on slab

In the midst of an enclosed porch over slab job. Plans initially included flash on un-vented roof, rigid foam on exterior, house wrap and fiberglass in walls.

Asked By Jason Schatz | Oct 16 14
5 Answers

Curbless shower with a PVC liner -- how to terminate the liner at the floor?

I'm installing a curbless shower----Concrete slab-on-grade with a sump for shower.
Using traditional method for shower floor---PVC liner, with pre-slope and top slope mud beds.
2x2 tile on shower floor and 18x18 travertine on bathroom floor.

My question is how to handle the waterproofing interface between my sump and the bathroom floor level (like where the curb would have been).

Asked By john walls | Oct 19 14
0 Answers

what is the best ventilation system for a passive design cafe/restaurant ??

we are trying to design a passive cafe/restaurant building and i want to know the best ventilation system to use for the building please.

Asked By monita taghva | Oct 20 14
1 Answer

insulation dew points, and archaic insulation

I have a couple of questions, both somewhat academic since there may be little to do about them.

I live in a 1938 1.5 story (Cape-style) house in St. Paul, zone 6. About 3 years ago the shoddily-added back porch was falling apart and the roof shingles were shot , so I tackled both in one, replacing the back of the house with a new addition, and re-roofing the entire house using this "cold roof" article in JLC as a model (in short, adds 3" XPS foam plus 1-1/2" air gap above the original roof): http://www.jlconline.com/rooftop-accessories/retrofitting-an-insulated-c...

Asked By Graham Allan | Oct 20 14
7 Answers

“Air-sealed” can light retrofit vs. Tenmat cover in attic?

I’m planning some air sealing work in my attic. I’ve got a bunch of recessed can lights to deal with, and I had been planning to use Tenmat rock wool light covers on the attic side. This would involve caulking (say, Tremco acoustical sealant) or foaming to seal the Tenmat cover, plus taping up any cuts to allow for electrical wires, etc. After first going into attic, pulling back existing insulation, sweeping the area clean, etc.

Asked By andrew c | Jun 22 14
2 Answers

An outside, completely isolated, balcony column structure

In an outside, completely isolated, balcony column structure that must be finished in stucco and built using steel studs, would it be possible for any moisture damage in the inside of it if we were able to completely seal the inside from the elements? In a 4c zone, applying stucco to acrylic panels to make a stand-alone column.

Asked By peter mare | Oct 20 14
17 Answers

Rising power plant energy cost

See attached....SDG$E(San Diego, CA) raised the minimum tier from 12 cents to 15. We don't buy in and didn't run the AC much this year in baking heat, probably what most are doing, that and getting off the grid. This is sign of those still on the grid having to pay for the ones that are off. In KS, cost went down from 10 cents last year, to 9 probably in fear of going bankrupt like Cali. Lets see what they do with gas.

How about where you live, going up or down?

Asked By Terry Lee | Oct 15 14
3 Answers

Window U-value comparison to wall R-value and window replacement

We have an 1870s Victorian farmhouse that doesn't have insulation in the walls, and to keep it simple, we cannot add insulation in the walls without going to great expense, more than we can afford.

Asked By Keith Miller | Oct 20 14
6 Answers

Reasonable retrofit efficiency goals

As I battle with an hvac solution for our home, we are leaning more and more towards trying to reduce the load further. I'll mention some details of my own house a bit below but I'm actually asking in hopes of a more generalized discussion of what a reasonable retrofit btu and ACH50 goal is.

I did some reading tonight in the hopes of answering this question but didn't find any useful rules of thumb. I know, the old HVAC rules of thumb have caused a lot of grief. I'm not asking for a rule of thumb about BTUs/sf for heat but rather what is rationally achievable in a retrofit scenario.

Asked By Keith H | Oct 19 14
5 Answers

Insulation design

Climate zone 2a.....south east Georgia coastal island. Bought a 1962 block one story house, The interior walls are painted block....we like the beach look associated with this concept. So, all insulation must be on the exterior of the house....which now us striped to bare block. Interested in the correct approach for water management and insulation. Exterior will eventually be cedar shingles.. Sort of thinking....spray closed cell between furring strips with ridged foam sheeting over the spray foam and strips. Then plywood covered with rain drainage screen topped with shingles.

Asked By Robert Brown | Oct 17 14
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