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1 Answer

Regarding Panasonic humidity/motion sensing fans

As the panasonic literature states - the options for controlling their humidity / motion sensing fans is : Motion on/Motion off - Motion on/Humidity off - Humidity on/Humidity off with a selectable timer.
I think this ties the two operations together on the same timer - Meaning, if you set the timer to 30 minutes, the fan stays on for 30 minutes after motion is no longer detected or a level of humidity is reached, etc.
This seems limiting and a waste of energy if the fan stays on for more time than needed.

In General questions | Asked By Nedjinski | Nov 19 17
3 Answers

Air return issue: What is best approach to diagnose why I am not getting good return flow?

House is about 3200 SQ ft. two story with a single air handler in the basement..
- (original contractor no longer living to question)
- air temp balance is hard to maintain both in summer and winter.
- Had two local companies visit wanting to add a second unit vs diagnosing existing return air paths.

In Mechanicals | Asked By BlueMTN | Nov 19 17
8 Answers

Roof membrane and live vegetative roof

Hey all,

So after Material quotes and city grants etc, it looks like its going to be viable go me to do a live vegatative roof (green roof) on the flat roof I've recently built.

now I'm thinking about what roofing membrane to put on, to go under the green roof. I am considering things like cost, longevity, ease of install, potential for leaks etc.

I'm in climate zone 6. My potential roof assembly is as follows:

9.5" I joists with R31 rockwool batting
3/4 plywood decking
6" polyiso at R34
1/2" roofboard
Roofing membrane ***
3" green roof assembly

In Energy efficiency and durability | Asked By Jamie B | Nov 18 17
8 Answers

Insulating a pole barn question(s)

I have a 24’x34’ pole barn that I want to insulate so I can add some intermittent heat while working out there. I live in Iowa. In the winter, we park our cars in the front and my wood shop is in the back. There is a ridge vent along the entire ridge (34’). No soffit vents or gable vents. I do not want to add a ceiling. This isn’t our forever home and only need it insulated enough to trap some heat in while working out there - maybe 3-4 times per month, for a couple hours at a time, during the winter months. I can’t justify the cost of spray foam (So please no advice on spray foam).

In General questions | Asked By Doug Kremer | Nov 15 17
4 Answers

I want to build a wall in front of a masonry wall that emits moisture.

Dear GBA folks,

This fieldstone carriage house, built in 1910, has 22" thick stone walls (see picture). Inside on the second floor, 2x4 stud walls built about 2" away from the stone are covered with 1" plaster.

In GBA Pro help | Asked By Robert Cramer | Nov 13 17
2 Answers

How do you introduce clean air into the house?

Nice thread on insulation types and issues. But once the house is air tight how do you get good clean air inside? I admit to being nervous about foam; if something really negative is found, removing the stuff might cost half the value of the house. All these materials are deemed to be "mold resistant" but what we do in our house creates water vapor and if not allowed to escape would provide the support for mold.

In General questions | Asked By TrueGrits101 | Nov 19 17
10 Answers

Ranch vs 2-Story Home

Generally speaking, if one is looking to build a 1,600 sqft home, which provides the better energy efficiency and less expensive route?

Having 2 levels of 800 sqft each seems like it would be better from an energy standpoint since there is less roof area and everything is compacted in a smaller pad. Cost wise there is less roof area to frame, insulate and install a roof on with a 2-story. There is probably some cost savings in flatwork and foundation with a 2-story since the footprint is smaller.

In Green building techniques | Asked By Peter L | Nov 16 17
12 Answers

Remodel - Insulating a permanent wood foundation (PWF)

Background
We recently purchased a log home built on top of a Permanent Wood Foundation (PWF). It's a ranch style (26'x47') single story. Built in 1980. We have completely gutted the basement. We are down to the 2x6 stud walls 1-foot on center of the PWF. Previously the house was heated via a wood burning furnace and electric baseboard heat, which have both been removed. We had geo-thermal installed utilizing the duct-work that was in place for the wood burning furnace. It's a ground source heat pump made by Water Furnace (5 Series).

In Energy efficiency and durability | Asked By Jeepasaurus | Oct 30 17
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
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