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3 Answers

Solar thermal is not dead

A multi-family solar thermal project in Alberta.


In Green building techniques | Asked By Aaron Gatzke | Feb 16 16
9 Answers

ERV temperature settings?

I recently purchased an energy-efficient home with many upgrades on that front. One of them is an EVR. While I understand and felt like we have benefited from the EVR, I am confused as to what temperature I should have the lock-outs set to.

Currently the builder put them to 30 degrees and 95 degrees. That seems cold/hot to have that air being pushed into the house. Can anyone share some thoughts logic on those settings and if there are different settings please advise why?

Thank you!

In Energy efficiency and durability | Asked By Tommy Barrett | Feb 14 16
3 Answers

How to insulate and/or air seal sill plate?

Our insulation contractor recommended that our builder insulate or seal the area where the joists meet the concrete basement wall on the exterior. We have plans to spray foam the rim joist area from the interior, but the insulation contractor said this area can be a major air leak. He doesn't do anything with the exterior and didn't even have any product recommendations. This area will have siding on two sides of the house (where the grade slopes). Thank you!

In Green building techniques | Asked By Carolyn Farrow | Feb 15 16
1 Answer

Is polyiso roof decking acceptable as exterior wall insulation?

A local roofing supplier is selling polyiso insulation boards for very cheap. Almost too cheap, and it has me wondering if it isn't the same kind of rigid insulation I am looking for for exterior wall insulation.

The folks at the supply house wasn't sure of the brand, so I don't know any of the details, but they told me the R value of an 1-1/2" sheet is R8.6. I have found "ValuTherm" which has the same specs. It says it is closed cell polyiso designed for roof decking and has a fiberglass facers.

In Green products and materials | Asked By Clay Whitenack | Feb 15 16
5 Answers

Air drying Ponderosa pine

I live in SW Colorado near a sawmill that has a lot of reject 6x6 and bigger ponderosa pine posts and beams that are too warped or twisted too much to be used. Normally these are cut up for firewood but I want to slice them into 3/4" thick end grain tiles, air dry and dimension them and use them for residential flooring. I'll use a moisture meter of course but would like to have a rough idea of time needed for air drying before I start.

In Green building techniques | Asked By Jack Tally | Feb 7 16
4 Answers

XPS over ratslab

Hello all,
I was reading a discussion about polyuso on a basement wall and am looking at using the same technique for my crawl space in NJ. However during the discussion Dana mentioned insulating the footing before putting on a rat slab something I can't do in m1950s built house.

In General questions | Asked By Chris King | Feb 15 16
4 Answers

Pondering methods of installing steel plate siding

Climate zone 4 marine near Seattle. I'm in the planning stage of a job to build a small craft studio, to be clad in part with "weathering steel" panels on the exterior. This stuff is fairly heavy and impermeable, compared to the cedar siding we usually install, so I'm trying to determine the best way to do it. The building will have a concrete slab floor, 2x6 walls with R21 batts, and an open rafter/car decking ceiling with 6" polyiso over it and metal roofing over the iso. The owner states that it will not be heated to normal indoor temperature much of the time.

In Energy efficiency and durability | Asked By David Meiland | Feb 15 16
7 Answers

Output air temperature of mini splits on heat?

I have a little experience with heat pumps and gas furnaces, and have always noticed the difference in temperature of the air coming through the registers. I read somewhere that heat pump air temps are usually 95* where gas furnaces get the air temp up to 115*.

I have looked around but can't find the output temps of mini splits. Is it the same as conventional heat pumps? I know that mini splits are supposed to be able to operate in lower outdoor temps compared to regular mini splits, and wondered if that translated to a higher output air temp.

In Green products and materials | Asked By Clay Whitenack | Feb 15 16
12 Answers

Best place to buy rigid foam insulation?

In general, where have you found the best price on XPS and Polyiso? Lumber yard? Big box stores? Other? We are in the design stage of a new custom home project and I want to analyze price/performance as we are creating the plans. In the past I have relied on my stucco sub to provide it in his bid, but we will install on this project. Thanks for your input!

In General questions | Asked By Bill Costain | Oct 11 11
6 Answers

German flangeless window install and flashing details

I have an upcoming job with German tilt turn windows, they don't come with flanges like US windows typically do. My install plan is to screw through the frame (unless someone has a better idea) and once installed I am not that concerned about getting them air sealed. What I am trying to figure out is what is the best way to integrate them with the WRB and make sure they are not going to allow water into the home? Anybody know of a manufacturer who publishes good instructions for this? Maybe a German site that shows the materials and steps? This particular manufacturer does not.

In Green building techniques | Asked By Bob C | Feb 12 16
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