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3 Answers

Lunos HRV system in cold climate?

We are building a 1,350 square foot single story passive solar home. Slab on grade, very well insulated, open concept living area, 2 bathrooms, 3 bedrooms. Our home is located in northwestern Ontario, Canada, with temperatures dipping to -30 degrees Celsius in winter. The winters are dry. Wondering if anyone has experience with the Lunos HRV system in a cold climate? Would there be issues with the heat exchange during cold days/nights? What about extreme differences in inside and outside humidity?

In Mechanicals | Asked By Vera H. | Jul 5 17
5 Answers

Radon vent

Can a Radon vent be tied, legally, into a plumbing vent or must it remain separate through the roof?

In Building Code Questions | Asked By Jerry Liebler | Nov 17 17
18 Answers

Residential frost-protected shallow foundation in central Mass.

We are planning to provide a monolithic pour frost-protected shallow foundation (FPSF) for a single story 1300 sq ft 2 bedroom home in central MA. Air Freezing Index is 2000. I have read through many different case studies, research papers, codes, etc and there is a bit of conflicting and locale-specific info so I am looking to see whether I understand what is required here. I am a newbie owner-builder. Any constructive criticism would be appreciated, but I don't want to foment any religious wars.

In Building Code Questions | Asked By Kenneth Gartner | Sep 2 16
2 Answers

GBA Construction Details criticism & question

First, I thoroughly appreciate the effort to organize and share a large volume of quality construction details on GBA. Excellent information.
However, I'm disappointed that the .dwg versions of details are incredibly time consuming to work with for the following reasons:

1. Details and objects are completely exploded which makes them very inefficient to work with and revise. Leader arrows are not even singular entities and are exploded into 4 separate objects. Hatches are often dozens of exploded objects which is painful to select in order to edit.

In General questions | Asked By Spencer Decker | Nov 15 17
5 Answers

Please Help!!! Dimple membrane a necessity?

In General questions | Asked By Rasheed Warith | Nov 14 17
10 Answers

Question on direct vent fireplaces

I am gut renovating and expanding a circa 1920 cottage. I am trying to get as close to net zero as I can. I am an architect fairly well-versed in the principles and techniques of net-zero, DER and Passivhaus my firm having designed and built two Passivhaus and 13 net zero homes, all of which have had their performance measured and verified. The point of this bragg-y credentializing is to head off the inevitable finger wagging that usually comes upon mention of the very idea of including a fireplace in a home that aspires to net zero. I get it. Not a good idea.

In Green products and materials | Asked By user-6954517 | Nov 18 17
5 Answers

Possible to use Vented attic in conjunction with Open cell spray foam?

Hello there,
I am a General Contractor in Miami, FL (Hot and humid weather!) and I may get screamed at for asking this question, but is it possible to use continuous ventilation at the soffits (vented attic) in conjunction with Open cell spray foam (sprayed to the underside of the roof sheathing)?

In Green products and materials | Asked By 5221lefty | Nov 15 17
7 Answers

Help with installing a solar water heater using solar electric modules

I'm a solar contractor in the Philadelphia region. I've installed traditional solar water heaters using flat plate collectors but a homeowner has asked me to install a solar water heater using solar electric modules and a heat pump. This is new to me, I did some basic online research and came across an article on this site written by Martin Holladay, "Solar Thermal is Dead."

In General questions | Asked By Anil Babooram | Dec 17 13
7 Answers

Flat roof attic insulation

My home was built in the late 1890s and has a flat roof. It has aluminium siding and it has two floors and basement. On the second floor, we have sheetrock ceiling. There is an older plaster and lath ceiling on top of the sheetrock. There is about a foot of space between the ceiling sheetrock and plaster ceiling. In the attic, there’s no insulation at all. On the edges, you can see the stud cavities that run down to the second floor. You can only see down to the second floor and not the first floor. So not sure if it is called balloon framing.

In Energy efficiency and durability | Asked By michaeldrehl | Nov 17 17
3 Answers

Cut-and-cobble for a three-season cabin

I have a 3 season cabin in (Zone 7) of northern Wisconsin. 2x6 walls 16" OC. The cabin is sheathed in OSB,

Exterior foam of 3" is not an option. The cabin is 20x26' and I plan to cut & cobble 2" XPS on a table saw and fill the cavity with fiberglass batts. Granted...this is time consuming....but there's no hurry. I realize this doesn't address thermal bridging. My concern is longevity with OSB in a northern climate & still being insulated. Yes...I will install a rainscreen if vinyl is not used for siding material.

In General questions | Asked By Dan Musielski | Nov 17 17
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