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4 Answers

Humidity-control switch - always on

We have a bath exhaust fan, controlled by a "Panasonic WhisperControl Humidity Sensing Switch". This switch works great in the heating season, automatically clearing moisture ( Humidity Control Advanced Sensor Technology which detects relative humidity and temperature and will turn on the exhaust fan automatically to keep it in check. The fan automatically turns off when the appropriate combination of humidity and temperature is reached, in all climate zones for all seasons. The WhisperControl Condensation Sensor also has a manual on/off control and a countdown timer. )

In General questions | Asked By curtis betts | Jun 28 13
3 Answers

100+ year old house in Wyoming with hip roof is hot as heck — should we vent it?

Our hip roof is primarily hip with 1 side gable and 1 rear gable. We have no soffit venting and 4 standard square roof vents plus 1 gable vent on the rear west facing gable.

Our house is horribly hot in the summer (we only have a ceiling fan and portable fans in the house an big radiators by all the major windows make an a/c unit troublesome.)

In Energy efficiency and durability | Asked By Natasha Sanderson | Jun 27 13
1 Answer

Options for HVAC for a residential renovation built in 1979 with no A/C

Hello all. New user here.

In Mechanicals | Asked By KENNETH GRAY | Jun 28 13
8 Answers

Leveling a wooden floor — how measure it and how to shim it?

100 year old house, 12x12 upstairs room with T&G plank subfloor. I want to level and strenghen. Room sags toward the center.

In General questions | Asked By Mark Miller | Jun 27 13
8 Answers

3rd Party HVAC design

So am a carpenter who is trying (and failing) to design my own hvac system. I am totally stumped on the Manual D calc portion of the project and wanted to find a third party to design the system. Third party design is referenced a lot in other discussions on this site but I have had no luck finding some one to do small residential. Can someone point me in the right direction on this?
should I be looking for an engineer?

In Mechanicals | Asked By tom fraser | Jun 3 13
3 Answers

Finishing drywall

Besides using latex paint, what considerations are there for painting drywall to allow drying of potential vapor within the wall to the interior? I will not be using plastic behind the drywall. Do satin and semigloss in rooms such as the bathroom cause problems? How many coats of latex before it becomes semi-impermeable?

In General questions | Asked By tom ruben | Jun 26 13
4 Answers

Flat roof

I’m designing a large, high-performing house with “flat” roof in Dallas, TX. In NM most flat roofs are done with .25/12 slope Built-ups or Modified Bitumen roof, but here since there is more rain fall, I’ll like to use .5/12 slope and higher-end roofing material. I would like to use mid-R30s insulation. My options so far are:
1. Fiber type: TPO, KEE or PVC with A) 1” polyiso above the roof decking and 8” OC foam under roof decking, or B) 5” polyiso above the roof decking.
2. 5.5” Sprayed CC Foam roof.

In General questions | Asked By Armando Cobo | Jun 26 13
13 Answers

Sealing/Insulating exposed ducts for evaporative cooler in Tucson AZ

I'm just getting done helping relatives move into a house outside Tucson, AZ. The house has an evaporative cooler on the roof ducted to each room. The ducts run out of the side of the evap cooler and across the roof splitting a few times and then heading down through the roof into each room. The ducts are rectangular metal ducts, sealed with mastic and then lightly painted brown.

In Mechanicals | Asked By James Howison | Jun 10 13
4 Answers

HRV ducting, minisplits, and exhaust fans

I am planning on heating my house with 2 minisplits ,one on each floor. I will have a propane fireplace as backup. Since I have no duct work the only air circulation will be the HRV..

I have read on this site an article on mini split air circulation which pulls the air from the bedrooms (farthest from the heat source )and fresh air supplies are in the center of the house ,closer to the heat source....my question has to do with exhausting the two bathrooms....would I use 200 cfm fans on a timer and vent them through the envelope as well as the range hood?...

thanks, Bob

In General questions | Asked By bob holodinsky | Jun 27 13
6 Answers

Wood-walled basement?

From what I've read it appears one can build a basement's walls out of wood. The wood is heavily pressure treated and specifically graded for use in foundations. Typical walls use 2x8 s on 16" or 12" centers and either 1/2" or 3/4" treated plywood. If the stud cavities are filled with air permeable insulation an interior air barrier must be used. The bottom of the walls is restrained by the basement floor which may also be made of PT wood or ,of course concrete and the top of the walls are braced by the first floor framing and sub floor.

In Energy efficiency and durability | Asked By Jerry Liebler | Oct 3 12
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