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10 Answers

Conflicting HVAC Quotes

The original design for my house was 1900 sq ft 1st floor (front faces due North). with a 1900 sq foot finished basement. 450 sq ft attached garage. It is a walkout that faces due West. Only the walkout wall is fully exposed (and will be covered with slate). Remaining basement wall exposure is 12" at the top (also slate covered). First floor and basement ceilings were to be 9'. Using Marvin Integrity fiberglass windows with LoE2 coating for North & South facing windows. LoE3 for East and West facing windows (only 1 5x5 facing East, and one 5x5 and one 2.5x5 facing West).

In General questions | Asked By Will Norris | Oct 4 12
6 Answers

Vent caps sans duct?

Does anyone know of a vent cap manufacturer that makes vent caps without a piece of duct already pre-attached?

I've got a "Heartland" vent cap for the dryer exhaust which works the way I'd like the rest of my caps to work - it installs over an existing piece of duct that protrudes from the wall.

I have looked at a few caps that don't have duct attached but they were all cheap p.o.s...

In Green products and materials | Asked By Lucas Durand - 7A | Oct 5 12
6 Answers

Passive House Consultant training

I'm considering taking the Passive House Consultant training program, and was curious if anyone out there has done it. I'm a LEED AP (BD+C, Homes) and a licensed architect with over 17 years of experience. I'm doing a lot of reading about the standard (the many articles and posts on GBA have been very helpful, thanks), but haven't seen much on the consultant training. Any opinions?

In PassivHaus | Asked By Roxanne Button | May 5 10
2 Answers

Cold climate vapor barrier

I live in Alaska. Do I need to have a poly vapor barrier to meet code requirements?

In Building Code Questions | Asked By michael o'Laire | Oct 8 12
14 Answers

Subslab insulation and bearing wall footings

I am getting ready to do the foundation work on the new home we are finally getting started with. I have some load bearing walls in the basement that will sit on poured footers. The footers are -2" down from the bottom of the slab so the insulation can extend over the projection and run into the foam on the ICF wall. However for the interior load bearing walls, I was considering installing these
-2" as well and continue the foam over top of them, and then the slab. As we all know compressive strength of XPS foam far exceeds loads imposed in residential applications.

In Energy efficiency and durability | Asked By Jesse Lizer | Oct 3 12
3 Answers

Need Help with Insulating HVAC ducts

To qualify for some energy efficiency rebates, we needed to insulate 25' of the HVAC supply ducts in our basement. I found this online that recommended using rigid Polyisocyanurate foam board to insulate the ducts.


In Green building techniques | Asked By Andrew Mutch | Sep 10 12
3 Answers

Gut remodel insulation?

We're gutting a kitchen and dining area, and are trying to figure out what insulation to use.

Wall construction is 2x4 stud with stucco exterior, interior will be sheetrock. House is in Northern Illinois.

Whats the best insulation to put in before drywall? We've looked at fiberglass batts (tricky as the studs are quite irregular in spacing) cutting 2" foam sheets and taping/foaming into place, and spray foam kits.

In GBA Pro help | Asked By Kris Martin | Oct 5 12
3 Answers

How to tack up 2" rigid foam under rafters?

It sounds like people use cap nails...but I can only find them in a 2" length (at most).
Are there longer nails available? Or am I missing a key step in installing the foam boards?

In General questions | Asked By Nick H | Oct 5 12
5 Answers

Humidity Problem

Posted this in a few places, just trying to get it seen.

Hopefully I can get myself out of this mess I got myself into :)

I recently built a pretty tight house with my old fashioned dad, I think we ended up doing a pretty good job with making the house tight, but didnt include any mechanical ventilation in the home. Right now in early october we are seeing relative humidity levels around 75% with temperatures inside of around 70 deg F.

In Mechanicals | Asked By Denis Recchia | Oct 4 12
4 Answers

I would like to insulate the outside of a 1930s 12x24x8 concrete block home

I would like to insulate the outside of a 1930s 12x24x8 concrete block home. Stucco on the exterior and plaster on the interior walls. I live in St. Louis, MO.

My home is heated with a large wood burning stove in the basement (also same block construction) I was thinking of adding exterior foam with a stucco like finish to keep the outside appearance as similar as possible.

Thank you,

In Energy efficiency and durability | Asked By Ed Martin | Oct 4 12
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