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3 Answers

Should there be dampers in return air ducts for zoned systems?

The HVAC team just finished installing a zone control panel to split the house into upstairs and downstairs zones. The house was originally built in 1950 with a single heat register and no A/C. It was retrofitted with forced air heat and A/C but the installers did not provide return air ducts for the upstairs. All was well in the winter but we experienced horrible temperature imbalance during the summer when the A/C was on (70F on first floor, 80F upstairs in the bedrooms).

In Mechanicals | Asked By David McKain | Oct 30 15
2 Answers

Airfoil receptacle box

Is any particular kind of foam (fire stop?) required when filling sealing chamber?

In General questions | Asked By Michael Geoghegan | Oct 29 15
9 Answers

Device that switches between ERV and HRV?

We live in a 1910 craftsman style bungalow in very northern Illinois (climate zone border 5a/6b) that has undergone some VERY heavy insulation/airsealing retrofits. Now as the weather gets cooler and the air dryer, the inside RH stays VERY high all winter.

We are thinking about getting an HRV or ERV as a remedy. But aren't sure which to purchase. (I've read extensively the blogs/Q&A on here [and elsewhere] regarding them).

In Mechanicals | Asked By David D | Oct 29 15
1 Answer

Information on Rex Roberts built home

I'm looking at a Rex Roberts home for sale on the North Shore in Massachusetts (see attached image). Am curious to learn if anyone has knowledge of how well Rex Roberts homes age (this one was built in 1964) and if there are typical problems specific to these homes as they age. I should also mention I'm a novice with green construction but learning fast!

In General questions | Asked By Christine Costello | Oct 29 15
4 Answers

Ideas for insulating cinder block wall interior

Hi. We are renovating a bathroom on a 1950's brick house in Connecticut, which has one westward facing cinder block and brick wall. It is brick facade, a 3/4" air gap, then a layer of 4" cinder block. Understood that the ideal situation is to insulate from exterior but this is not an option for us, so we are looking to do it properly from the inside.

In General questions | Asked By G S | Oct 29 15
4 Answers

Exterior rigid foam and gable of unconditioned attic.

I'm building a one-story home, with an unconditioned attic. I will be installing four inches of exterior rigid foam. Does the gable also require exterior foam? If not, what's the most cost effective way to finish the gable?

In Green building techniques | Asked By James Timmerberg | Oct 29 15
1 Answer

Renovation of a 200-year-old farmhouse

I am in the beginning stages of renovating my 200+ yr old farmhouse. This is a post and beam house that has been in my family since 1834 and I am the 6th generation to call it home. It sits on a 250 acre dairy farm in Central New York that I help my father run. Since it has quite a family history I want to make sure any "improvements" that are made are made right. I plan on gutting the entire house in phases as there is not any insulation in the house and the electric is 1950's era that is in need of an update.

In Energy efficiency and durability | Asked By Ed Smith | Oct 29 15
2 Answers

Room above garage

One more question on my room above garage. The home is in zone 5 and the garage is 24'x24' The floor system has 16" deep tji 16' on centers. I will be filing between the joists with mineral wool and then Solitex Mento for air tightness with 2 1/2 " of 8lb Roxul IS Board as a thermal break then covered with 5/8" drywall. I plan on using strapping 24' oc however where should it be placed.

In GBA Pro help | Asked By Scott Goodman | Oct 28 15
8 Answers

Air Sealing Lights

Dear Martin,

A while back you had said about ceiling lights with an attic overhead: The best approach to air seal semi-flush lights which hang 12" from the ceiling (and air flows around them) is to install airtight electrical boxes -- for example, Airfoil boxes or Lessco boxes in the attic. We have old construction.

In Energy efficiency and durability | Asked By R Rafferty | Oct 27 15
10 Answers

Foundation insulation details

I am hoping to meet with my foundation contractor in the near future and want to make sure I am as close as possible to having my ducks in a row. Can you guys take a look at the insulation details below and see if I am on the right track? An explanation of my plan:

In Plans Review | Asked By Jim Tyler | Oct 21 15
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