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2 Answers

Water heaters / insulation

I am remodeling a 2 story, 4 bedroom, 3 full bath home. This house is old, added on to multiple times and has no insulation on exterior walls. The furnace and hotwater heater are giants and also old very non energy efficiant appliances.

I'm in central illinois so winters are not to extreme but can be at times. I have a $60,000 budget. I am doing 95% of the work myself to save on labor cost. I am having a contractor I trust to come in and help with supporting a second story structure due to opening up a kitchen into dining and living room.

In GBA Pro help | Asked By Thomas Priddle | Apr 7 13
2 Answers

Attic storage insulation details

Attic storage -- some people gotta have it. What would be some ideas to insulate this type of area where a plywood walking surface is necessary, and joists are shallow (2x6s)? What about pull-down stairs?

In General questions | Asked By Dennis Dipswitch | Apr 7 13
2 Answers


I am working out the final drawings for a double wall house and I know that there can be significant thermal losses at the rim joist so I am trying to do something about that. My plan calls for moving the rim joist in on the mud sill that the floor joist butt up against by 3 ½ inches. This will give me room for 2” of Styrofoam plus the 2x12 on the outside. Basically the 2” of foam is sandwiched between 2 pieces of 2x12. My house is a 2 story so I plan on doing this to the second floor as well.

In Energy efficiency and durability | Asked By Paul Fowler | Apr 7 13
2 Answers

Window and siding detail

I'm hoping someone can point me to a detail that my designer can drop in plan.

Here is what I am considering for the exterior wall section as follows (from interior to exterior):

-Half-inch air sealed drywall (all the interior walls are covered with shiplap siding)
-2x6 stud
-Compacted cellulose
-15/32 exterior rated OSB (seams sealed with Nashua #330X Extreme Weather tape)
-Dupont Commercial D house wrap
-Half-inch Rigid Foam (all joints taped)
-Dupont Rain Screen Battens on studs (or maybe 1x3 nailers as battens)
-Insect sheet at the bottom as well.
-Hardi Planks

In Green building techniques | Asked By Steven Knapp | Apr 5 13
11 Answers

Reverse Flash & Batt


I'm having a new home built in a very cold climate(Edmonton, AB, CAN) and it will have an unvented cathedral ceiling.

In order to save money I was thinking of going the Flash&Batt route but after reading about dew points and cold climates I'm worried there might be a condensation risk between the foam and the batt.

I was wondering if its possible to reverse the method and put the vapour/air barrier(the ccSPF) on top of the permeable layer? It seems to make more sense in a cold climate to do it this way.

In Energy efficiency and durability | Asked By Dave Johnson | Apr 2 13
3 Answers

Floorplan and systems design help

We are building a new home near Edmonton, AB. I don't know which climate zone to reference based on the US map provided here but I would guess we are a zone 7. Here is some climate info:

5500-6000 HDD annual average
340 mm average annual rainfall
115 cm average annual snowfall

There will be 3 adults and 2 kids (8 and 1 currently) in the house. We are pretty much set on the floorplan at this point but the systems design is a long way from completed. I want a reasonably efficient house at a reasonable cost and this is the plan today (after flip-flopping many times):

In Plans Review | Asked By Shaun Malmo | Apr 5 13
0 Answers

Stucco or plaster for AAC interior?


I have an AAC building and will be stuccoing the exterior soon. I will go with the STO stucco basecoat mesh, and finish. I could also use this on the interior, but it may be overkill. I know that plaster can be used on the interior, but I don't know what product or who sells it. I like the spanish knife texture so if there was an AAC plaster product that could be applied like that, it would be great. It would also be easier and faster than doing a stucco basecoat and finish coat treatment.

Any recommendations from anyone who has done AAC interior finishes?

Thanks & Regards,

In Green products and materials | Asked By Lance Pawlikowski | Apr 5 13
3 Answers

Rigid foam insulation over concrete in basement

I am finishing a basement with poured concrete walls. There is no insulation over the concrete on the exterior. On the inside, I would like to install 1" rigid foam and cover with 2x4 framing with batts of Roxul between studs. What type and finish of rigid foam would be best -- Polyisio, EPS, XPS, or other? I can think of reasons for using each of these but wonder which solution keeps moisture vapor issues to a minimum?

In General questions | Asked By tom ruben | Apr 5 13
3 Answers

Applying Stucco to Rigid Foam over CMUs

I am planning on exposing my earth-bermed house on the west side. We live in Ithaca, NY. Zone 5, sometimes 6. Unfortunately, the house was built 30 yrs ago as a rectangle, North to South. The short side is facing South. We only have windows on our short south side, so we are exposing the CMU blocks on the west to introduce some windows.

I am going to add 3" of rigid foam over the vapor barrier that will go over the CMUs. Then, 2 layers of building paper, the lath, then stucco.

In Energy efficiency and durability | Asked By Rick Ryan | Apr 4 13
10 Answers

Are lightweight thermal mass systems effective?

We have an on-going discussion about Thermal Mass Systems that is getting nowhere. Heavy-weight mass walls and floors are easy for all to understand, like concrete, rock, adobe, rammed earth, water, etc.; however the issues we have is with Light-weight mass like some ICFs and CIPs. How can an INSULATED product be an efficient thermal mass system at the same time? If the insulation is preventing the concrete core to get any heat/cold, how can that provide good thermal mass results. Also with products like AAC, if they are insulated CIPs, how can they be good thermal mass products?

In General questions | Asked By Armando Cobo | Apr 1 13
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