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2 Answers

Whole House Exhaust Fan?

I am working with a client that would like to install a through roof (roof mounted) whole house exhaust fan. The house has all cathedral ceilings. It is currently poorly insulated, poorly air sealed and has a ton of glass in bad locations.

It is in Zone 5. Interior can get pretty warm inside during the summer. His previous house had a whole house fan that he thinks did a great job flushing hot air at night to "quickly" bring down the interior air temp.

In Mechanicals | Asked By Chris Harris | Jul 24 12
10 Answers

Horizontal Wood siding

I'm in the process of detailing a rainscreen for a house near Seattle (4C, although it shouldn't matter), and was curious expansion joints.

I was wanting to do horizontal butt-jointed 1x6 cedar boards with (ideally) no gap between each board. This would be over a rainscreen with vertical furring strips at 16" o.c.
It seems like there would be a real issue of the boards expanding. I've seen this system used before (or at least it appeared that there were no gaps) so I'm curious what the right detail would be.

In General questions | Asked By Daniel Stewart | Jul 23 12
10 Answers

Interior Foam Insulation vs exterior

I thought I had things all figured out. I'm in central Wisconsin, Zone 6, I was planning on 2x6 construction with (2) 1" Layers of exterior polyiso held by 3/4" furring strips via fastenmaster's specs. Hardieboard only requires 3/4" screw penetration, good to go...but all the 5/4 and 4/4 trim (frieze, band corners) made by Smartwood, Miratec, Azek, Certainteed requires 1 1/4 penetration.

In Energy efficiency and durability | Asked By Brian Van Handel | Jun 20 12
3 Answers

chimney top dampers?

Hi All,

Does anyone have any experience or advice regarding chimney top dampers, eg the "Lock Top II": http://www.woodlanddirect.com/Chimney/Top-Sealing-Chimney-Dampers/Lock-T...

I'm looking for something simple, safe, and reliable to cut down on leakage from a fireplace. Can any of these work in conjunction with a damper at the firebox (or is that overkill)?

In General questions | Asked By Cramer Silkworth, PE | Jul 23 12
2 Answers

Rigid foam over brick exterior in Maryland

I my house has all masonry wall with no insulation. From the inside I have plaster, 3/4"-1" cavity, 4" concrete block, and finally 4" of brick on the exterior. I wall to add insulation and change the exterior to cement siding. I already own 50 sheets of XPS so I would to use it on the project.

In Energy efficiency and durability | Asked By James Eric | Jul 21 12
4 Answers

HRV retrofit to concrete walled-home with high humidity


We have been living in a 10-year old 2150 SFT home (with full walkout basement) in east-central Illinois with the following features:

1. Exterior walls are ICF (Insulated Concrete Form) with EIFS siding.
2. No gas/oil connection to home (all electric appliances/furnace).
3. Regular Air Conditioning with an exterior condenser unit (3-ton).
4. Regular exhaust-only fans for the bathrooms
5. Windows are double-paned but not good and there's a draft thru the sills during winter that I try to block using foam stoppers.

In Energy efficiency and durability | Asked By Venkat Y | Jul 22 12
0 Answers

What would building experts use an in-house sensor network for?

I'm toying with the idea of putting together a sensor network in my house, and wondered if people had any plans or suggestions about what they would monitor.

I'm in part motivated by the Arduino-based version of the DZ DIY zoning project (see http://diy-zoning.blogspot.com/ ) where sensors like temperature and moisture are linked up to give a dashboard view of the house (Austin, TX, Zone 2).

In General questions | Asked By James Howison | Jul 23 12
2 Answers

Interior Greenhouse - wall and ceiling assembly concerns


In Energy efficiency and durability | Asked By Rick Dominick | Jul 20 12
0 Answers

Heat pump air handler and ducts in basement zone 4A

We live in a 1200 SF 1976 ranch house (all roof and basement) with electric heat and appliances. I was thinking of having a air source heat pump installed to supply heat and and AC. I have added 6 inches of unfaced insulation to attic and don't feel that running ducts thru that unconditioned area and low slope acess with an R-8 insulation rap would be beneficial. I was wondering if installing the air handler and ducts in the basement would be better. Are there any concerns for this approach? Thanks for your input. Glenn

In Mechanicals | Asked By GLENN MCIVER | Jul 23 12
4 Answers

Water-source heat pumps

Hello, I just bought a house with a 16 year old HVAC roof top unit that needs replacing. The heating unit .is a gas furnace (as a part of the unit) and the original unit had an AC seer rating of 11. I live in Chico, Ca. where the summers are very hot and the winters rarely get to freezing. The house came with a swimming pool. I was wondering if it would make any sense to replace the roof top package with a water source heat pump tied directly to the swimming pool?? It would be a split system with the refrigerant to air system in the attic connecting to the existing ductwork.

In Mechanicals | Asked By mike mccluskey | Jul 20 12
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