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2 Answers

High-solar-gain windows only on the south side?


zone 4/5 border. southern exposure faces ocean.

do we need high solar gain (.47 SHGC - ALMOST qualifies for Canada zone C, even) in all windows or just the south facing ones? Low E 180 glass...



In PassivHaus | Asked By pat rowland | Oct 30 13
3 Answers

Foil-faced polyiso on both sides of a 2x4 exterior wall?

Hello all --

In GBA Pro help | Asked By Jeff Nelson | Oct 30 13
1 Answer

UFFI insulation removal

Working on a clients home in Ontario Canada and discovered UFFI in the walls
of the room being updated
The UFFI is deteriorating, and there is some moisture in the walls.
Would like to remove and dispose of the UFFI, but need to know if there are
any regulations regarding removal or disposal.
None of the government agencies seem to have the answers, and I have
searched the web extensively.

Anyone offer some insight into this?

Many thanks.

In General questions | Asked By Joe Cotter | Nov 30 11
2 Answers

Hanging floors from SIP walls

Hello --

I'm planning to build a SIP house in Northern California next year. We're working with a potential GC (currently being paid hourly for drafting and design). We started with a design we liked, and have worked with him to refine. He's just passed the design on to a structural engineer. I'm growing concerned that although both of them have SIP experience, they are approaching the project as a standard design that happens to use SIP walls and roof. But maybe this is a realistic approach?

In Green building techniques | Asked By Nathan Kurz | Oct 29 13
8 Answers

Honeywell ventilation system

Hi - I did ask this question on a blog with a bunch of old posts - so I am not sure if it will be seen. Hoping someone here can help.

I just moved into a 2 year old 3000 square foot house in the Sacramento, CA area. As you know, the summers are hot and dry.. and the winters can get chilly (but not that bad).

In Energy efficiency and durability | Asked By Joe Pa | Oct 29 13
7 Answers

Vented ceiling: dense-packed cellulose vs. Spider or Optima

I have read the "how to build a cathedral ceiling" several times, but am still confused on details for air gap/dense pack system.
In the case of building a VENTED cathedral ceiling which is dense packed with small particle fiberglass or cellulose, Should there be a air barrier on the top side ( air gap side) of the insulation? The way I understood some of the posts on this topic, the baffle vent must be air tight for some types of insulation, and not for others. Can someone clarify?

In Energy efficiency and durability | Asked By Dirk Gently | Oct 29 13
13 Answers

Mitsubishi vs. Fujitsu?

We are ready to install three one-to-one ductless mini-split heat pump/AC units in our 35 year old colonial located in Freetown MA. We have talked to two installers and now are stuck trying to decide which brand is the better choice for us. Note, we chose the installer based on his price, which was significantly less than the other. We just can't decide whether to go with Mitsubishi or Fujitsu.

In Energy efficiency and durability | Asked By Nina Lafferty | Oct 29 13
4 Answers

Looking for a "green" modular builder willing to ship to NW Canada

We are building a duplex that will not use any fossil fuels up here in Yellowknife, Canada. (18 hours north of Edmonton - Climate zone 8 - same as Fairbanks). Our lot is on 100% granite so no basement, no slab on grade - we're building a "box on legs". We aim to invest as much as we can in insulation and then heat with wood pellets & some of our local hydro electricity ($0.30/kWh)

We also want green materials which are hard to find here & our trades are very expensive so many people are going with prefabricated modules.

In Green building techniques | Asked By Andrew Robinson | Oct 29 13
8 Answers

Concrete balconies and thermal breaks

On a residential application with a 2-story home using ICF walls and an InsulDeck 2nd floor. When it comes to thermally breaking the exterior concrete balcony, there is not much out there in details that can properly thermally break such a setup.

I have found this German made product called "Schock"

It is designed to carry the load and thermally break the concrete balcony. It runs for around $80 per linear foot. So on a 22' wide balcony, one is looking at around $1,760.

In Green building techniques | Asked By Peter L | Oct 27 13
4 Answers

How to insulate an overhang in zone 3?

I have a small overhang on a second floor bedroom that extends over the front porch. I had planned to complete seal the overhang to isolate it from the rest of the structure and add R30 open cell between the warm and cold area. Another contractor has suggests that I should not seal this space. He would instead include this area in the building envelope while also spraying R30 open cell on the bottom of the subfloor. So should I create a sealed space or integrate it into the envelope?

In Energy efficiency and durability | Asked By Steven Knapp | Oct 27 13
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