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4 Answers

Dryer vent in air-tight Passive House

I am building a house in the Seattle area to Passive House standards. After spending countless hours sealing every crack, seam and penetration to achieve under 0.6 ACH, creating a 4 inch diameter hole in my air barrier pains me. I've looked into condensing dryers that are used in some European Passive Houses, but they seam to take much longer to dry and use lots of water. Since I will be installing a vented dryer (unless someone can come up with another solution), are there ways to make the dryer wall vent more air-tight when the dryer is not in use?

Asked By Gerald Blycker | Nov 21 14
29 Answers

Trusting a heat load calculation & downsizing...

I'm replacing my furnace & had a Manual J-based heat load calculation done by a reputable person using the Rhvac software. I paid a sizable amount of money for this heat load to be done - but I was tired of going to contractors who relied on rules of thumb & made educated guesses based on experience. I just want the concrete numbers to back up any claims.

Asked By Jeff Watson | Nov 15 14
2 Answers

Is this a sufficient wall system for my basement?

Zone 6a. One inch foundation plus type two eps foam adhered directly to concrete with PL. Seams taped and corners spray foamed. 24 oc studs with r20 fibreglass Batts. Should I include a poly vapor barrier before drywall? I've been told to omit this as the foundation plus should be sufficient enough for a vapour barrier. Also should I spray foam the small portion of exposed concrete at the top of the wall between the type two foam and the Sill plate? I should also mention it's an eight foot foundation with about six and a half feet below grade.

Asked By Mark McKenzie | Nov 20 14
5 Answers

We ran into a few deep uninsulated roof channels

Too little to have a cellulose sub. Are you better off packing them full with pieces of fiberglass batts, or risking air movement by sliding a loose batt down? What is the R factor of hand-packed fiberglass? Thanks.

Asked By Robert Mason | Nov 20 14
3 Answers

Dense pack cellulose rig rental in Philadelphia area

I've decided to make a DIY attempt at installing dense-pack cellulose to a fairly small section of the thermal envelope in my home (which happens to live under a floor, well above grade). I'm looking for the highest-power cellulose blower I can rent, preferably an Intec Force 2 or better, plus a kit for reducing tube diameter to the appropriate level and providing whatever stiffness/bendiness is needed for the circumstance. Anybody know where I can rent such equipment in the Philadelphia area, preferably less than 1 hour drive?

Asked By Andrew Levitt | Nov 19 14
19 Answers

Is 1" enough?

We are constructing a home in far western SD (Climate Zone 6b)....There is a lot of bedrock here so we have opted to build a post frame (pole barn) style structure. From the outside in, our wall 'sandwich' will be
1-pole barn style tin wall covering
2-Tyvek
3- 1" Tongue and Groove XPS foam
4-Half inch OSB attached to the girts
5- 7" of cellulose filling the curtain walls
6- OSB on the shop walls and Drywall in the house.

Asked By daryl stisser | Nov 16 14
6 Answers

I air-sealed my attic too well!

Not really, of course. But here's my story:

I moved into a 1350sf ranch home (3/4 basement and 1/4 crawl) in Columbus, OH last year and have been working to air-seal and insulate it. I ran a blower door test before I began just to be nerdy and track my progress. Initial leakage was 3075cfm @ 50 Pa, about 9.7 ach50. I started work in the attic, sealing up everything I could find before blowing in cellulose over my skimpy loose fiberglass.

Asked By Ben Wilson | Nov 20 14
6 Answers

Suggestions for insulating a large garage workshop

Hi everyone. I just purchased a property in western Massachusetts zone five a. I am planning to renovate the existing 24 x 60 barn for use as a year-round workshop. The building is slab on grade with 2 x 6 framed walls 24 inches on center, sided with rough pine board and batten nailed to the studs and bracing. Currently, there is a bit of air exchange between the interior and exterior due to some of the battens pulling away from the nailers.

Asked By Benjamin Jones | Jul 18 14
3 Answers

Best way to insulate an old attic?

I am the owner of a 100-year-old two-story house in the 5A climate zone. The house has a full-height attic space, which is currently uninsulated. The attic has actual floor boards in place over the joists, which could be removed, but would be a lot of work. Right now we just use the space as storage, and don't plan to convert it to living space. During the winter i run into huge icicle and ice dam issues. My question is, would it be beneficial to me to insulate the parts of the roof that are accessible(id say 70% is not covered)?

Asked By Brian Grimsley | Nov 19 14
1 Answer

Rigid foam over WRB

I am finishing up a full kitchen remodel that pretty much required me to rebuild 25' of exterior wall in my 1600 s.f. 1950s ranch located in Portland, Oregon (zone 4 marine). It is a 2x4 wall with R-15 fiberglass, existing 1x8 shiplap board sheathing (less some areas with wood damage, yes we do have termites in the NW), window and door rough openings flashed to a Tyvek primary WRB and air barrier. I would like to add 1-1/2" of rigid foam with taped seams and a 1/2" rainscreen before replacing my cladding.

Asked By David Fraser | Nov 19 14
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