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2 Answers

Balanced ventilation year round when windows are closed?

I want balanced fresh air exchange to improve indoor air quality and reduce humidity in the winter. And also to improve indoor air quality and reduce humidity in the summer. It seems like hrv/erv are designed for only cold or only hot humid climates not a mix of the two.

Asked By Miles Adams | Dec 17 16
2 Answers

Sanity check on very preliminary rough estimates of heating energy usage

Hi to the Forum. A few months back we bought a home in zone 5 (Northern Nevada at 5000') that was solely heated with electricity. We intend to install hydronic heating throughout and want to do it right. I was going to do a BEopt calculation but the computer I downloaded that software to was damaged and is currently out for repairs and bringing my heating upgrade project to a standstill.

Asked By Roger Smith | Dec 14 16
2 Answers

Incorrect plumbing joint fix for basement bathroom install

5 years ago we had our main sewer line replaced with PVC line which 90s into our main 4" stack. City and plumber failed to put in a 90 y / floor drain and we we're told we would be fine with basement bathroom install. More recently, the driveway has been redone. Present day, 2 plumbers have told us that due to proximity of the joint to the wall, they cannot guarantee cracking will not happen on the short run of 4" that goes out the straight out from the 90. There is an 8" fail-safe as the pipe is under the foundation.

Asked By Mike Tew | Dec 10 16
7 Answers

What direction should I go with my new/used home?

I purchased a 23 year old home to accommodate my growing family. It was constructed with double wall construction, wood foundation, Envirovent system etc. We live on Nantucket Island.
I am planning to install a mini split system and have questions on further improvements, possibly solar, that are upcoming.
My first inclination was to update systems based on the recommendations of local hvac contractors until I realized that my new home is unique and that I might need specialized consultation from someone more familiar with this "type" of home.
Any advice or suggestions are welcomed.

Asked By todd stout | Nov 29 16
10 Answers

Polyiso foamboard (foil-faced on both sides) used in unconditioned space

Hello All,

I live in Portland,OR climate zone 4 & 5 marine.
I consider it mainly a heating climate and lots of rain.

I have a cape cod style house with 13/12 pitch roof on the main roof.
I have three gable dormers on the front, two new ones and one existing all with 20/12 roof pitch.
I just had ridge vents installed on the main roof and all three gable dormers.

I have managed to keep my new HVAC ducts in the floor joists and the are only exposed in the knee wall area before to going down into the (conditioned) floor/ceiling joists on the way to each room.

Asked By Chalin Hutasangkas | Nov 13 16
8 Answers

Which foam system to use in air-sealing the attic in an older home before adding cellulose?

I am getting two different recommendations from contractors and could use some guidance. We live in Portland, OR in a 1951 ranch-style house that was extensively remodeled in 2005. We started to significantly upgrade our attic insulation & air-seal and discovered that we have a vermiculite/asbestos remediation problem to solve first. Some of the abatement cost is covered by the ZAI Trust fund.
Result- all the existing insulation (vermiculite, old cellulose, blown-in fiberglass) is being removed first. Then, air seal and blow-in cellulose to R49.

Asked By Kent Snyder | Nov 16 16
5 Answers

Is closed cell spray foam between rafters in an old house a good idea?

To all, but especially to Dana Dorsett and Martin Holladay,

Asked By Rebekah Haworth | Nov 15 16
5 Answers

I need help insulating my unvented cathedral ceiling

Here's what I have: I am building a house in my existing pole barn. When I built it, I put my roof nailers on 2' center, then put down fan-fold insulation, then placed my metal roof. I am going to leave my trusses exposed on the inside for a cathedral ceiling, and was wanting to put metal up for my ceiling between the trusses.

I am trying to figure out how I can insulate this. Can I use rigid foam board and put it all the way against the fan-fold and make it airtight, then put up my interior metal?

All the help on this would be much appreciated. I am stumped. Thank you.

Asked By Thomas Duncan | Nov 11 16
5 Answers

OK to put rigid foam between rafters to convert a vented attic to unvented, for storage?

To all,

We live near Chicago and have a split level house built in 1959. I would like to use rigid foam to convert our two vented attics to unvented so that we can use them for storage. The rafters are 2x6, so there is 5.5" of depth under the roof deck to put layers of rigid foam into as a "stack of pancakes" between the rafters. I would also like to attach 4'x8' sheets of rigid foam (at least 1/2 inch thick) to the lower edge of the rafters to prevent thermal bridging.

Asked By Rebekah Haworth | Nov 9 16
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