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4 Answers

Durability problems: Keeping paint on an historic house?

Our local historical society maintains an 1843 farmhouse as a museum. For the last fifteen years it has been unoccupied, except for occasional guided tours (monthly?) and two big day-long festivals annually.

Exterior paint lasts only a few years, and the society has asked me for suggestions on steps to take that might prevent paint from peeling so quickly. Anybody on this forum ever worked with something like this? I assume there's a vapor problem, or worse.

In Energy efficiency and durability | Asked By Andy Chappell-Dick | Aug 19 16
2 Answers

ERV with dual ECM motors and good controls

Is there anything else besides Zehnder (a bit pricy, but quality supposed to be great) and Recouperator (looks dated and also pricy considering accessories) on the ERV market that would fill below requirements:

1. 2 ECM motors.
2. Economizer or free summer cooling (assuming humidity levels are not crazy)
3. Being able to set it to slight positive pressure (and ramped up speed to get to it while using clothes dryer and wood burning stove)
4. Controls good enough to do #2 and #3, optionally in conjunction with existing 3 zone Prestige IAQ and HZ432 ran system.

In Mechanicals | Asked By Nick Zees | Aug 12 16
2 Answers

Moving from exhaust-only to an HRV - outside venting question

Hi all, appreciate any help you can give.

I live in Minnesota (6B on the climate map) and I have a 3 year old house with bath fan exhaust only. There are 3 bath fans on the second floor that run constantly. House is about 3800 sqft now and will be almost 5000 sqft when basement is finished.

I'm thinking about switching to a HRV while the basement drywall is still open and shutting down the bath fans. In mechanical room HVAC is high efficiency so plumbed intake and exhaust. There is a 6 inch flex fresh air in the mechanical room seemingly just for the water heater.

In Mechanicals | Asked By Ben H | Aug 19 16
3 Answers

Insulating an attic (Boston area) - how to do it best?

Thanks in advance to all of you who will finish reading this post :) This is my first remodeling in my first house, so I appreciate all help.

We live in Boston metro area (zone 5) and in a 1901-built house. The top floor has cathedral ceilings (probably converted from the attic in the 1960s or so - we are not sure). Right now it serves as our bedroom with master bathroom + exercise zone. It is crazy hot in the summer and surprisingly tolerable in the winter. We finally have some money now to insulate it, and so I started my research.

In Energy efficiency and durability | Asked By Anna CB | Aug 18 16
3 Answers

Wall assembly

I posted about wall construction last winter, building in Atlantic Canada. Wondering about WRB's and the best ($) interior smart vapor to use? 2x6 oc framing with 1/2" plywood taped for air barrier, 4" eps, furring stripes then vynil siding. Will I be ok with regular tyvek on the exterior of the plywood? Should I use certianteed, intello or db +? Thanks Kris

In Energy efficiency and durability | Asked By Kris Currie | Aug 18 16
5 Answers

Under cathedral ceiling - EPS or polyiso?

I have a vented cathedral ceiling that is as follows. I am in climate zone 5 so I assume this is an R-38 assembly:

1. Asphalt Shingles
2. Roof decking
3. 12" I-beam joists full length with styrofoam vent channels stapled to the underside of the decking
4. 10.5" fiberglass batts in between I-beams
5. Visqueen sheeting stapled up underside of I-beams over entire underside of roof.

In Energy efficiency and durability | Asked By Kyle S | Aug 18 16
4 Answers

Why do I have a musty mildew type smell in my conditioned crawl space?

The house we moved into is now 11 years old. We have been here for 2 years. Just this year we started having a mildew basement type smell coming into our first floor when we run the ac. It is summer and hot. We have a conditioned craw space that was put in when the house was built. There is not junk down there. We have a heat pump and ac unit and a gas furnace in the craw. Everything was fine until this summer when our first floor began to smell like a musty basement.

In General questions | Asked By linda larochelle | Aug 18 16
5 Answers

Replacing fiberglass with foam to save space

Hello,
I'm trying to make room to run a 3.5" x 10" HRV duct in my new-build cathedral ceiling cape, unfortunately as a bit of an afterthought. Unfortunately, I don't have a convenient interior wall to use, so it needs to be installed in an exterior wall.
One way I can make room is to take one rafter bay and one stud bay and use RMax polyiso there instead of the fiberglass I will be using everywhere else. This way I can achieve approximately the same R Value in less space, freeing up room for the duct I wish to install.

In General questions | Asked By Justin Smith | Aug 18 16
1 Answer

SIPs or nailbase with spray foam?

I recently read an article from Building Science Corp regarding unvented ceilings. If I understand it correctly, if I use SIPs or Nail Base as the main insulation/structure of the roof, I can also add closed cell or open cell spray foam on the underside of the roof to increase the insulation. Is this correct? Is one foam better than the other? Could you also use any other type of insulation on the underside of the roof? I thought if you used insulation on the exterior of the roof, you needed to use an insulation that would allow the ceiling to dry inwards.

In Energy efficiency and durability | Asked By Kyle Rice | Aug 18 16
18 Answers

Attic insulation quandary

Seeking advice on renovation plans for a 1910 house in ND - Zone 7.

HOUSE DETAILS:
- 2 1/2 stories above ground with full basement.
- 2nd story has 'sun porch' facing south.
- 2 layers of siding. Inner layer has lead paint (of course)
- Insulated in the 70's with formaldehyde foam, holes drilled through exterior to fill cavities.
- High efficiency propane furnace, forced air.
- 2 chimneys.
- 1st in middle of house used for original oil-burner furnace and water heater. Now used by wood fireplace in basement.

In GBA Pro help | Asked By Tim Lange | May 16 16
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