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4 Answers

Are stainless steel metal finishes for plumbing fixtures more sustainable than polished chrome?

We are trying to ascertain the environmental benefits or hazards in selecting stainless steel finishes or polished chrome finishes for our plumbing fixtures for our clients. Any insights will be appreciated.

In Green products and materials | Asked By Paul Gleicher | Feb 4 15
5 Answers

Are Canadian and European triple glazed windows really worth the price premium over Intergity triple-glazed?

At 1 1/2 to 2 times the cost-or more, are the these windows really justifiable vs the Integrity fiberglass line?

In Green products and materials | Asked By JAMES KREYLING | Feb 8 15
3 Answers

Ventilate or apply more insulation to roof containing furnace and AC?

We have a 2 story Cape with a single air handler running off a heat pump, (down to 35) & a condensing furnace (For colder days). The heat pump is also our AC unit.
The bulk of the units are in the attic with only the heat pump/ac condenser out side.
We have a roof and wall sealed and unvented attic. There is no insulation under the floorboards.

In Green building techniques | Asked By Thom Cadley | Feb 8 15
29 Answers

I have narrowed my search for fiberglass triple-glazed windows to Fibertec and Thermotech — seeking comments about these two

I am building an Energy Star certified home with fiberglass, triple glazed, low e casement windows and slider/patio doors in Connecticut. I prefer using a Canadian company because of their expertise with fiberglass, triple glazed windows and sliders. I must have window specifications for the Energy Star certification, preferably NFRC ratings or at least independent U, SHGC and VT value ratings. Window ratings do not seem to be diificult to acquire but slider/patio door ratings can not be provided by some manufactures for fiberglass triple glazed sliders and French doors.

In Energy efficiency and durability | Asked By JOSEPH POLAND | Jan 15 13
3 Answers

EPS/XPS or ??? on interior side of cathedral roof in zone 7

I have a vented R40 cathedral ceiling (parallel scissor truss). It currently has two layers of R20 fiberglass batt insulation above the drywall. I would like to add some insulation; the only option is to add it to the interior..
Can I do this and if so how much EPS/or XPS or ??? can I add? I have room to add 6 inches of rigid foam or similar.

In Energy efficiency and durability | Asked By tim brown | Feb 7 15
2 Answers

What is the vapour permeance of plaster and lath?

I live in an older house with plaster/lath.plaster/1-2inch barnboard, 2x4, wood siding/vinyl siding, i am wondering what the permeance is of the interior side.

In Energy efficiency and durability | Asked By Alan B | Feb 7 15
1 Answer

EIFS over lap siding

i have a 2 story built in 1920. It has no moisture issues. I am having the exterior walls dense packed with cellulose. The exterior is horizontal lapped siding over 1x6 horizontal sheathing. After dense packing... can I apply EFIS using house wrap and 2" foam board over the lapped siding? ..or must it be removed down to the sheathing?

In Green building techniques | Asked By Todd Phillips | Feb 7 15
17 Answers

New study on heat pump water heaters' reliance on the home's heating system and viability of ducting the HPWH


This came out sometime in 2014 and I haven't seen anything about it before.

The points that I took from it are:

  • The heat "stolen" by the HPWH is less than expected, at least when located in a room that is partially on the exterior surface of the home.
  • Exhausting the HPWH to the outside without also ducting its intake can have a harmful effect on the home's heating energy use, since it needs makeup air, which comes from outside and can be even colder than the output air of the HPWH.
In Mechanicals | Asked By Nick Welch | Jan 9 15
10 Answers

Possible allergic reaction after fiberglass replacement?

I just wanted to ask a quick question to see if anyone thinks or has had experience with a client getting respiratory problems after fiberglass batt removal and replacement? We had a rodent infestation in our crawlspace and had the old infested fiberglass removed (after trapping and killing all rodents) and new fiberglass batts installed. The new batts are the formaldehyde free Eco Batts by Knauf. They were installed on the ceiling of the crawlspace, under the floor of our living space. The installers were never in the living space of the home.

In General questions | Asked By morgan martin | May 15 11
7 Answers

Closed cell on skip sheathing?

Please excuse the blurry photo. What it shows is 1x6 skip sheathing over 2x4 rafters. There is asphalt felt over the skip, and a snap-lock metal roof over that.

The owner (local government entity) wants to convert this attic into conditioned space, and is requesting quotes for a project that includes spraying closed cell foam under this roof deck.

In General questions | Asked By David Meiland | Feb 6 15
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