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5 Answers

Basement floor and wall details

Re: FHB Feb/Mar 2005 article "The Stay-Dry, No-Mold Finished Basement" and 4/7/14 GBA Q&A "What's the Best Basement Flooring System?"

Project: Converting an existing basement to living space in a 1900 house in Portland, Oregon.
See attached sketch for detail.

Questions about how to finish the basement while minimizing mold potential:

In Energy efficiency and durability | Asked By Miyeko Endy | Jun 15 16
16 Answers

How do I vent this floor sleeper assembly? Or do I need to? Help!

Redo of old commercial alley space.. 2 story brick bldg turned into sfd

Floor assembly:
1. built on existing slab on grade that is about 1" above grade in an alley
2. existing slab had some cracks in it and some plumbing with short plumbing trenches in it. 6/23/15
3. 6 mil poly layer
4. 2x6 pt sleepers joists at 16" oc solid blocked about 4' oc 6/25/15
5. 3" closed cell foam sprayed in joist bays 6/30/15
6. 3/4" t&g osb floor sheathing 1st week of July/15
7. 5" wide 3/4 solid red oak flooring on flooring paper. 8/12/15
8. Client comment about cupping 10/15 or 11/15

In GBA Pro help | Asked By Carey Hoobler | Jun 6 16
8 Answers

Ductwork in Exterior Wall

I know, don't do it. Here is my problem. I am renovating my daughter's house. She wanted a bearing wall removed and I knew that two supply ducts would be an issue. They are 6" ducts running from the basement to two second floor bedrooms. Furnace is near the center (front to rear) of the basement at the end of the basement. Bedrooms are above this end of the house.

In Mechanicals | Asked By Mark Reinmiller | Jun 15 16
35 Answers

Post-cure/long term off-gassing with Bayer’s Bayseal closed cell spray foam insulation (“SFI”)

I am considering having Bayer’s Bayseal closed cell spray foam insulation (“SFI”) installed in the attic and basement rim joist at my New Jersey home. I am interested in hearing thoughts on the recent concerns over off-gassing of the SFI that I have been reading about. My questions assume SFI installation gets done correctly (I have read about the improper installation problems causing odors). Anyway, the issue of concern/interest for me is long-term off-gassing AFTER a properly done SFI job.

In Green products and materials | Asked By D S | May 14 14
4 Answers

Affordable Air-to-Water Heat Pump for climate zone 6B, Colorado

I'm looking for an air-to-water heat pump that I could use with a low temperature hydronic distribution system for space heating. I would also like to use the heat pump as the preheat for domestic hot water.

The mini-split air-to-air heat pumps are pretty ideal in many climate zones in the USA. On the western slope of the Rockies in Colorado, air conditioning isn't usually necessary. So I'd prefer one heat pump to provide space heating and much of DHW.

In Mechanicals | Asked By Pat Kiernan | Jun 14 16
8 Answers

Minisplit controls?

I'm planning a ducted minisplit system for our renovated large house.
It will be 4 floors (inc basement and cathedral attic) but likely 6+ zones given the size of the house (6k above grade).
Im looking at mitsubishi hyperheat or the fujitsu ducted sustems.

Q. Is there a major difference in the contrils in terms of features / quality?
Q. How do these work in a whole-house heat/cool use? I have wall mounted units currently but the have IR remote controls. What about zoning a whole house?

In Mechanicals | Asked By Edward Cambridge | Jun 13 16
14 Answers

Are there any advantages to using a radiant barrier in an attic?

I'm thinking of installing a radiant barrier in the attic, above the insulation and attached to the bottom of the truss top chord. For my own house.

In Energy efficiency and durability | Asked By Ryck Voisard | Jun 14 16
6 Answers

Exterior closed-cell spray foam to an existing house possibly a slightly different angle

First I apologize as this topic has literally been beat to death..... That said this is a slightly different twist that I cannot find any details on.

Existing house is a 1985 modified split entry. The wall assembly as it exists in the areas I have taken it apart are (from inside out): Paint of various kinds, drywall, foil faced kraft paper (independent of the fiberglass batts), fiberglass batts in a 2x6 wood wall (assuming R-19), fiber board sheathing, probably Tyvek and an old Masonite siding.

In Green building techniques | Asked By Lonney Olson | Jun 10 16
9 Answers

Cost-effective double stud wall with interior wall as load bearing?

For a two-story home with double stud walls in a cold climate, it seems you avoid a lot of thermal bridging if the rafters/TJIs for the second floor are supported by the inside stud wall. I have questions about how to do this "load-bearing inside wall" assembly most cost-effectively. The approach needs to be something a small crew with no crane can implement (so ballon framing is out).

In Green building techniques | Asked By John Huber | Jun 14 16
0 Answers

Lunos e2 vs. TwinFresh Comfo RA1-50-2

Looking for thoughts or feedback on the thru-wall HRV's/ERV's. Specifically the Lunos e2 system vs. the TwinFresh Comfo RA1-50-2.

What I know about the two systems-

They can both work in unison (every 70 seconds or so, they reverse supply and exhaust), during this time the core is regenerating.

The Luno e2 has a remote wall mount datalogger and control head. (an add-on expense $500+). The units (sold in pairs) and are a couple hundred dollars more than two TwinFresh units too.

The TwinFresh has a higher air flow capability, and higher electrical requirement.

In General questions | Asked By Brad Hardie | Jun 14 16
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