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8 Answers

Insulating under footings?

Hello, I'm building a house for my parents in northern British Columbia. We are shooting for a superinsulated and air tight building. It's will be a story and a half, on an ICF foundation crawl space.

Planning on doing the GWB, 2x6 (structural/utillity chase, with either dense-pack cellulose or rock wool batts),1/2" ply (taped to become the vapor/pressure boundary) with a 12" Larson truss on the outside of that (dense-pack cellulose), then WRB, rainscreen, Hardiplank.

Planning on beefing up the ICFs with 6" of EPS on the outside, with also 6" of EPS under the slab.

In Energy efficiency and durability | Asked By Richard Alton | May 17 14
6 Answers

Hot water heater strategy

Been thinking about the best way to set up my hot water heater system and wanted to bounce my idea past the readers of GBA.

Zone 5A - Central Illinois. Water heaters will be located in basement. Family of 5 (3 young kids) with plans to accommodate elderly parents if necessary in the near future.

HVAC system is a 3-ton GSHP with desuperheater that can provide some water pre-heating but not enough to meet DHW demand by any means.

In General questions | Asked By Robert Kohaus | May 22 14
10 Answers

Where the heck are the podcasts?

I can't seem to find the podcasts anymore. Could someone please direct me to the list of what's available and how to get them? Thanks - Jim

In General questions | Asked By jim blodgett | May 22 14
15 Answers

Still getting 'Access Denied'. Jim Wright

Still getting the 'Access Denied' message on the 'Q&A' section.

In General questions | Asked By Jim Wright | May 16 14
6 Answers

Installing insulation board over cedar siding on unsheathed & uninsulated (filled with brick) walls of 1890s farm house

Hi. I've been trying to read up on the best way to add insulation to the walls of an 1890s farmhouse but I haven't come across a similar situation/reply.

In Energy efficiency and durability | Asked By Keith Miller | May 22 14
6 Answers

My outdoor spigot when opened has no water coming out

My outdoor spigot when opened has no water coming out. Valve is open inside house as well...
Help.
What is internally in the spiogot to not allow water flow?

In General questions | Asked By Kenneth Clement | May 14 14
3 Answers

Best insulation for a mix of brick & wood?

There's a lot to be found about insulating brick, and about insulating wood...but what's the best solution for interior insulation for a combination of both? This is for a wall in a multi-wythe brick home, and this particular area has some wood framing in it (the wood frame goes to the roof of a portico). (See photo)

My instinct is to use rigid foam, pressed up as close as possible to close conductive loops. But clearly, there will still be lots of air in the wood-framed area.

What's your take on this?

In Energy efficiency and durability | Asked By Kimberly Howell | May 21 14
1 Answer

Wood basement drainage?

My understanding is that very well executed drainage is vital to the success of a PWF basement.
The designs I've seen typically have a crushed rock or washed gravel layer under the basement's walls and floor, 4" or 6" thick. They also backfill at least 1/2 way up with the drain rock. My questions are: Would a 1" layer of Roxul " Drain Board be a proper replacement for the back fill rock? Is filter fabric on the outside of the wall's drainage medium needed?

In Energy efficiency and durability | Asked By Jerry Liebler | May 21 14
6 Answers

Do wireless switches save energy?

I know zip about electricity. Consider two homes almost exactly the same, both conditioned by heat pumps (to drop gas out of the equation). But, one has traditional electrical wiring/conduit to all loads and switches. And the other only has wiring and conduit to the loads but no wiring and conduit from loads to switches because the switches generate radio frequencies and are self-powered (flipping them or ambient room light solar generates enough power to send the signal). Considering the whole electrical load (including heating/cooling in Northern Zone 5a), which home uses more energy?

In Energy efficiency and durability | Asked By Gordon B | May 19 14
17 Answers

Floor insulation, Roxul vs closed foam

The foundation of my house (1152 sq/ft) is post and pier and there is no perimeter enclosure.
The bottom of the 2x8 floor joists are about 40" from the ground.

I am considering two methods of insulation.

The first method is 7.25" thick Roxul batts (R30) that are covered with 7/16" OSB sheets.

The second method is 1.5" (R10) of sprayed closed cell foam.

The cost to me of both methods (if I don't count my labor with the Roxul) is nearly identical, about $2000.

The Roxul has the advantage of about 3x the R value of the foam.

In General questions | Asked By Jim Wright | May 14 14
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