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1 Answer

Mini split for multiple rooms with small loads

I asked an earlier question about how to deal with my existing central heat and no a/c system. Based on the responses, I'm planning to repair the ducting system some. However, I still need a cooling solution and doubt that I can effectively centrally cool the house due to the vertical split level nature of it. I already know that 1/2 of my cooling load is in rooms that effectively don't have central ducting.

So I'm looking at using either a multi head mini split to cool the house or multiple single head units. I'll probably get at least one heat pump unit so I have that option.

In Mechanicals | Asked By Keith H | May 6 14
5 Answers

Cantilever a stove/fireplace off the side of a house?

We are designing an 850 sq foot house plus loft for climate zone 4A, western nc, and will be trying to do a pretty good house, sealed and insulated all around, including underneath as it will be on piers on a sloped lot.
The area has experienced extended weather related power outages in the past, and so a non- electrical back-up heating source is needed as an adjunct to the ductless mini split we will be installing.

In General questions | Asked By Marla Umhoefer | May 3 14
4 Answers

Install rigid foam on bottom of rafters in unvented cathedral ceiling filled with OC foam?


The house is new construction, but OC spray foam has already been installed before I was aware of the potential moisture concerns cited on GBA (otherwise I would have gone with closed cell). So I'm wondering, to address thermal bridging from the rafters, as well as prevent interior moisture from migrating through the OC foam and rotting the roof sheathing, is it a good idea to install an inch or two of rigid foam on the bottom of the rafters directly underneath the sheetrock?

In Green building techniques | Asked By Stephen McMurray | May 5 14
0 Answers

Looking for biomass boiler experts


I am interesting in installing a biomass boiler but I would like first to get sevreral estimates. So far I have found the following sites:



I have not heard of these sites before. However, I got a reply from the first ones already saying they are working on my request. Could anyone point me to any other professional or web site where I can receive more quotes.

In General questions | Asked By Stefanos Anastasiadis | May 6 14
2 Answers

Cedar wall shingles and rain screens

Wondering what's the better way to make a rain screen is. First option- on the exterior of the studs I'll have 2" of polyiso then felt paper. Then I was thinking of ripping 3/8 plywood into 2"or3" strips and attach them vertically thru the foam into the studs. Then ripping plywood for the horizontal battens for the shingles every 5". Seems like a long time at the tablesaw. Never done this before, might make details around the window tricky?

In General questions | Asked By Seth Kelley | May 5 14
5 Answers

Overpour or not?

I'm preparing to build a super-insulated spec house (R-36, R-60) in far northern Wisconsin. The site has an insulated 28'x40' slab-on-grade already there from a previous owner, and I'm pondering the best way to incorporate in-floor radiant heat into the house. (There is no need to inform me that most energy-interested folks think that in-floor heat is overkill for a super-insulated house.) I just built and sold a similarly-insulated house with a heated slab and no heat source on the second floor, and am looking to do that again.

The two methods I'm considering are these:

In Green building techniques | Asked By Josh Jipson | Apr 26 14
2 Answers

Can you use a tank-less Heater to do both DHW and space heating (hot water baseboard)

We want to combine both DHW and space heating, as we have limited space

In Energy efficiency and durability | Asked By Joan Blood | May 4 14
1 Answer

What are the three most common mistakes with vapor retardars

what are the three most common mistakes with vapor retarders?

In General questions | Asked By Randy Nilsson | May 4 14
4 Answers

I will be adding a room to my house this summer and I am looking at a couple different wall configurations.

Any comments / suggestions / criticisms more than welcome.

Obviously these are not wildly original, they are based on so many great posts here and also on recommendations from BSC.


In Green building techniques | Asked By Greg Smith | May 1 14
3 Answers

What type of building envelope should I use on my resided house in Seattle?

We have a two story house in Seattle that was built in 1976. It has 2x4 exterior walls with R-11 rolled fiberglass insulation between the studs – has brown kraft paper vapor barrier on the inside of the house walls, has foil vapor barrier on the inside of the unheated garage; then on the studs is foil backed kraft paper, ¼” of white foam insulation board, then aluminum siding. It looks like they use slanted 1x4 bracing in the corners for shear bracing. There doesn’t appear to be any plywood on the exterior of the walls.

In Green building techniques | Asked By dale luhman | May 2 14
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