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8 Answers

Heat pump dryer for $598 (if you're in southern Ontario, Canada)

This dryer has been discussed several times on GBA and i bought one (for delivery soon) being ventless and quite energy efficient.

Since its discontinued and this is an amazing price i thought i'd post it here for anyone who may live where they can get it


Discussed on GBA

In Energy efficiency and durability | Asked By Alan B | Jul 7 17
2 Answers

Can you connect a bubble up raydon system to the air system?

An air system was already installed for radon when we purchased our house. We had a water system installed after (bubble up) and the installer said he could run the water system vent into the air vent. We just had the bubble up serviced by another company and was told what the first guy did was illegal and it will cost $4 to $500 to fix it. Just trying to find out if it is legal to do it.

In Building Code Questions | Asked By maglady | Nov 9 17
33 Answers

Another garage heating question


So I'm building my dream shop/garage, then I going to build my house.. So my wife is making sure I stay on budget.

Building is 64'x 40' x 14'

ICF frost walls that will be 4' below grade and 2' above grade then 12' of 2x6 walls on top for 14' ceiling.
Walls will be taped and sealed OSB best I can and have 3" (reused) Polyiso on exterior and filled with Roxul.
Attic spaced will have blown in cellulose, R???
Floor will have 4" foam under slab. If needed??

South facing side (64') will have 4 large 5' x 5' windows, casement style on half of 2 windows.

In Mechanicals | Asked By Dave B | Oct 4 17
8 Answers

Seattle Insulation Retrofit

Location: Seattle, WA, Marine Zone 4C
Type of Construction: Wood frame single family residence
Year Built: 1947
Size: 690 sq ft main floor, 380 sq ft basement

I purchased a home several years ago that had previously been a rental house for 30+ years and owned by the same family since it was built. It has seen very little in the way of alterations and updates. Which is good and bad. No need to undo poor workmanship but just about everything needs upgrading. Perhaps a blank slate?!

In General questions | Asked By Jeremy Sharp | Nov 7 17
4 Answers

I have a question about Heat recovery ventilators.

I have a home with with 10" of dense pack cellulose in the walls and 14" in the celling.
I am looking to install a h.r.v. I have a very open floor plan and would like to use only one vent in and one vent out. Drawing air from the upstairs bedroom and putting new air into the living room downstairs. Air would travel through the stair well at the other end of the house . Calculations say I need about 100 cfm. Is there any problem moving this amount of air through only one duct?


In Mechanicals | Asked By george finlay | Nov 8 17
6 Answers

Casting concrete to repair rubble foundation?

I have a crawlspace that leaks air badly in the winter and I would like to insulate (I live in Minneapolis, MN for reference). Upon embarking on the job, I uncovered a rubble foundation that is in need of repair. This foundation is part an old extension to the house and is of much lower quality than the original limestone brick foundation. It also looks as if it has been repaired at least once in its life as there are some random chunks of red brick and glass embedded in the wall which I doubt were original.

In Energy efficiency and durability | Asked By Frank Thorton | Oct 16 16
2 Answers

Closed cell foam in in vented roof

I have been able to avoid using spray foam up until now but with recent code changes in our area we are now forced to use it.

On a current job we are framing a new roof directly on top of the existing old roof sheathing because the owner wants to expose the hand hew beams of the original frame below. The new rafters are 2x8 and the plan is to spray the bays with closed cell foam on a warm day and then immediately sheath and roof.

I’m a concerned because the rafters will have no time to dry out before being foamed and I'm concerned about lumber shrinkage

In Energy efficiency and durability | Asked By Judson Aley | Nov 8 17
4 Answers

Air Sealing Question

When we built our garage/apartment, we sealed the perimeter of every stud bay to the Zip System sheathing panels with Tremco acoustical sealant. We also caulked or foamed every joint and space between the framing members, around windows, doors, header and top plates, etc. It was a lot of work, but along with the other air sealing details, it seems to have resulted in a VERY airtight structure.

One thing we did NOT do was to caulk the drywall to the wall studs, as we were not in town when the drywall was installed.

In Energy efficiency and durability | Asked By Nancy Broadbear | Nov 8 17
5 Answers

Why does insulation have to contact six sides?

On the internet I've read about 15 years worth of claims that insulation must contact all six sides for it to be effective, but haven't seen an explanation why. Yes, I've read many times that a building's insulation and air barrier must completely surround the conditioned space and be in contact with each other, but can't find the science behind it explained. I would sure appreciate a scientific explanation from anybody. Thanks very sincerely.

In GBA Pro help | Asked By JeffSch1 | Nov 8 17
1 Answer

EPDM Gasketed Joints vs Cement "Welded" PVC Joints for Flue Gases

I'm interested in warranty/service life of EPDM gasketed joints (in PVC or polypropylene) vs that of PVC cemented (chemically welded) joints. Am installing a furnace and would like to use polypropylene for the combustion air/vent pipes 'cause in many environmental impact categories the material itself is superior to PVC. Further, I guess I believe PVC bought at a big-box store by my HVAC contractor might not be designed specifically for HVAC venting.

In Green products and materials | Asked By Gordon B | Nov 8 17
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