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13 Answers

Air conditioning for a radiant heated home?

We're planning a new two-story house build in Ottawa, Ontario, probably equivalent to zone 6/7 on the US chart. We are planning to use hydronic heated floors on all three levels.

What are the most common approaches for adding air conditioning to a house with radiant floors? We will have a fairly comprehensively ducted HRV/ERV system.

The house will be superinsulated (~R40 walls, R60 attic, R20-30 below grade) with southern exposure and proper window shading to limit solar radiation. Finished plans should be around 2500 sqft.

Asked By Lance Peters | Feb 5 17
0 Answers

Heating and insulating for a wide interior temperature swing

I'm planning out my garage, which will be mostly for cars and storage. I may install a small mini-split or PTAC to keep the garage above freezing, and to occasionally cool the building if I'm working in it in the summer.

I've got a couple questions:

Is there any green motivation for insulating the building beyond what fits in the stud-bays (2x6 likely), given that I'm letting the temperature swing widely?

Is there any issue with operating a mini-split with a 40F building temperature?

Are there any vapor management concerns for a building that has wide interior temperature swings?

Asked By John Ranson | Feb 26 17
1 Answer

insulating a garage

I am seriously considering converting my garage into a workshop that I want to use year round. It is cement block construction and I would like recommendations on insulating the walls. I will probably drywalling after and then installing shelving etc. Thanks

Asked By JATotter | Feb 26 17
4 Answers

Integrating Ducted Mini-Split with HRV


Asked By John Brown | Feb 25 17
4 Answers

Hydronic Heating System Hydraulic Buffer Tank vs Hydraulic Seperator

This question might be more appropriate in a plumbing forum but I have had such great and thoughtful responses in the GBA forums I look to here first. This is also a hydronic heating mainstream topic which should be appropriate for GBA.

Asked By Roger Smith | Feb 26 17
8 Answers

Heat-pump water heater for an all-electric garage apartment?

We our building a detached garage w/ 2nd story apartment (1 bedroom, ~900 sq ft conditioned space) & debating the system to heat water:
- Primary purpose for the garage apartment is for our mothers to live in as they age. Mainly for safety reasons, we're not having gas service to the apartment (could do relatively easily - main house has gas service)
- Cooling-dominated climate (Houston TX)

Asked By Robert Hallenbeck | Feb 8 17
7 Answers

Follow up question re: basement subfloor (climate zone 7a)

A couple of weeks ago I asked a variety of questions pertaining to my livable space basement retrofit for a 1974 home in climate zone 7a. Recap: there is no exterior foundation or under slab insulation, etc. No water penetration issues into the interior but part of the basement has shown recurring efflorescence and some spalling in a few places.

Asked By user-6759891 | Feb 24 17
4 Answers

Casement windows?

I'm looking for highly efficient triple glazed windows with a high solar heat gain coefficient for use on the south side of a new construction home in Massachusetts (Climate Zone 5). I like Schuco windows, however, I am looking to compare with a window that performs similarly but doesn't open into the living space. Any suggestions?

Asked By user-6776655 | Feb 26 17
0 Answers

Load Specs- understanding manufacturer's fastener spec

Hello again GBAer's

I'm having trouble interpreting a load spec for a Simpson fastener (SDWS221000DB). Looking at a table that addresses my specific application (furring strip on 6" of exterior board foam insulation, 16" studs), the heading of the table reads:

"Maximum Allowable Cladding Weight to be Supported (psf)"

This seems fairly clear, except doesn't 'psf' refer to a _pressure_? But this wouldn't make much sense.

Asked By Gerald Pehl | Feb 26 17
4 Answers

How to insulate a cathedral ceiling from within the rafter bays

I have a zone 7 1840s house-and-a-half style house, with the second floor walls going about 4 ft up, then sloped cathedral ceiling for another 3 ft up, capped by the flat ceiling and a 4' high crawl space attic. Essentially the second floor looks like a rectangle with the upper corners knocked off, and every surface but the top and bottom is exterior facing. So the sloped ceilings are the thickness of the lathe and plaster, the rafters, and the roof.

Asked By Terry Sharpe | Feb 24 17
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