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1 Answer

poly under slab and over sill ?

We are building a super tight insulated house (passive inspired). My Q is does the 10 mil poly that we will put under the slab have to run up the interior basement walls and over the sill. Our house has a full basement, the concrete exterior has been waterproofed, insulated and back filled. Our sill seal will be acoustical sealant, EPDM gasket and PT sill. I understand the poly is a vapor barrier and the concrete is the air barrier. I have had a hard time finding info on the web about full basement as opposed to slabs.

Asked By Jocelyn Smith | Nov 25 14
13 Answers

Spray foam insulation

I have a 100 year old house in Zone 5. There is a sunroom (approx. 5'X20') on the south side of the house which is all windows. It is built on piles (about 4' to the bottom of the joists) and open underneath with lattice. The room is open to the living room of my home and is heated by 2 forced hot water radiators. When we bought the home the floor was insulated from underneath by batt insulation and rigid insulation between the joist cavities. We had an energy audit performed when we moved in and were told this was all good. Still, the floor has always been cold.

Asked By Danny Mac | Nov 17 14
9 Answers

Mold on inside of plywood sheathing

I recently purchased a super insulated house in the Concord, NH area. The house is 3 years old. From my investigation and discussions with the previous owner the wall system is double stud insulated with 3 layers of 3.5" Roxul Comfortbatt. The sheathing is Huber Zipwall with taped joints. The siding is cement board clapboards nailed directly to the sheathing. The inside is drywall and I'm told gasketed at joints and electrical outlets. there is no interior vapor barrier and the paint appears to just be regular latex.

Asked By Aaron Saucier | Nov 25 14
10 Answers

Designing a passive solar / net zero house in NC Mountains

My wife and I are designing a new mountain home in Banner Elk, NC. We are in the initial design stages with our architect and are confused by the numerous options to consider. Our house will be built in the Eagles Nest community which has a pacific northwest lodge feel. Our home site is at a 5,000 foot elevation on the mountain ridge with a northern view.

Asked By bill Moseley | Nov 23 14
5 Answers

Locating flue hole without removing wall paneling

I am trying to install a wood stove in a room that has paneling on the walls. The chimney flue has been covered by the paneling. I'd rather not remove the paneling because it was glued to the wall when installed. I have tried several ways to do this but was not successful. I dropped a measuring tape down the chimney, took a measurement but was way too low for the flue when I laid the measurement out. Check the room next to this room and found the chimney and a sealed flue on the opposite side of the chimney. Thought about knocking out the plaster or concrete seal, still an option though.

Asked By Louie Bruno | Nov 19 14
2 Answers

What U and SHGC is needed in temperate weather conditions to achieve NetZero?

In this wonderful community, Energy Efficiency is often been in reference cold climates. I live in California and am in the architectural stages of building a NetZero house.

We have two seasons: Summer and Rainy. The rainy season lasts from November to end of Feb and during those months it can actually freeze - although I doubt if we ever have more than 5-6 freeze days a year. In the summer we never have more than 5-6 days above 90 in a year. We probably have at least 330 days of sunshine.

Asked By Katherine Bretz | Nov 24 14
2 Answers

Dense pack Q: Can fiberglass batts be extracted without demo'ing a wall?

OK, a few more insulation questions more question, then I think I've hit my quota for the week (year?) :) I want to learn a bit more about dense packing a wall just so I have that as a data point to make my final decisions.

Asked By Ryan Griffin | Nov 24 14
3 Answers

Blow cellulose into air space between 4" gap from floor to slab? Other options?

Hi, love this place, it has answered so many of my questions but this one I'm stumped on.

Asked By Luke Kelly | Nov 25 14
13 Answers

Rigid polyiso in side attics?

As a spray foam alternative, I'm considering using continuous rigid foam along the 32ft long x 7ft slope in my side attic and just spray foaming in the lower joist bays and places where taping is difficult. The attics are about as simple as can be with no dormers or other obstructions. I will need 8" of polyiso to meet my disired R-value (R-48), while keeping the 2x4 rafter bays wide open for ventilation. There are also HVAC ducts and plumbing in the attic, which is why I'd like to convert it conditioned space.

Asked By Ryan Griffin | Nov 22 14
11 Answers

What is the efficiency of gas powered infrared radiant heat?

My project: Climate zone 6A Hortonville, WI 54944 Energy source: electric or propane, no natural gas available

An earlier post about heating garage brought up the possibility of gas powered infrared radiant. I'm familiar with these devices, but I literally can't find any information from the manufacturers regarding their efficiency. They all claim to be "very efficient" for various reasons, but I can't find hard data.

Are they rated by a percent like house furnaces? I.E. Are they in the range of 80% efficient ceiling hung unit heaters?

Asked By Rick Van Handel | Nov 24 14
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