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4 Answers

"Healthier" HVAC materials

We are installing a new HVAC system. We are chemically sensitive and would like to use products that do not off-gas, if possible. Does anyone know of a healthier substitute for neoprene duct connectors, and standard duct tape or mastic? Also, we would like suggestions for a healthier duct insulation material. It is difficult to find such products. Green does not necessarily mean healthier, as we all know. Thanks!

J. Thurber

In Green products and materials | Asked By Jas Thurber | Jan 30 12
3 Answers

Adding rigid foam over existing insulation

I like in northwestern North Carolina (zone 7) in a Cape Cod style house. The upper rooms are pretty uncomfortable in the summer. You can feel the heat radiating into the room I presume because it basically has "attic" on three sides that is unconditioned space. There are seven foot-high knee walls on two of the three interior walls in each bedroom with a bath in the middle. The knee walls have fiber glass batt R-19 which sits just proud of the 2X4 stud bay.

In Energy efficiency and durability | Asked By Donald Guilbault | Jan 29 12
2 Answers

Avoiding the Global Warming Potential of Mini-Splits?

There has been much discussion previously on the surprising global warming potential (GWP) of extruded polystyrene (XPS), at 1430. According to Wikipedia--so it must be true--the refrigerant R410A has a GWP of 1725. R410A is commonly used in heat pumps. Unintended consequences?

In Green products and materials | Asked By TJ Elder | Jan 29 12
13 Answers

Using a heat pump water heater for basement dehumidification -- has anyone done this?

Currently I am running a dehumidifier about half of the year in my basement, along with an electric water heater. I am currently considering a switch to a heat pump water heater. The GE model, for example, is under $1000, so this is an investment that could pay for itself by taking $150 to $200 a year off our electric bill.

I am wondering how much dehumidification I can expect with the various products now out there -- the Rheem, Geyser-R, GE, AO Smith.

In Energy efficiency and durability | Asked By rich cowen | Oct 4 11
4 Answers

What wrap or spray insulation would be recommended for use on aluminum beams that will penetrate a building?

Exploring building a cantilevered balcony using aluminum beams in order to fit the beams between existing floors. Looking for a material to prevent heat loss and condensation without corroding the beams.

In Energy efficiency and durability | Asked By Louise Walker | Jan 28 12
2 Answers

New York Passive House responds

Below, see the response by New York Passive House to PHIUS's cease-and-desist letter. (For an updated report on this controversy, see PHIUS Tries to Trademark ‘Certified Passive House Consultant.’)

Dear NYPH Member,

In PassivHaus | Asked By Martin Holladay | Jan 28 12
8 Answers

PHIUS lawyers accuse New York Passive House of stealing PHIUS's “trade secrets”

Lawyers representing the Passive House Institute U.S. have sent a cease-and-desist letter to a regional Passivhaus organization in New York, accusing the group of stealing PHIUS's e-mail list. The letter includes several “demands.”

Three New York Passive House board members have issued a letter denying PHIUS's charges. They say that the e-mail list used by New York Passive House is their own, not one stolen from PHIUS.

To read the details of this story, see the new paragraphs appended this morning to yesterday's news story:

In PassivHaus | Asked By Martin Holladay | Jan 27 12
10 Answers

Open-cell foam or cellulose over ceiling?

The ceiling has been dropped 1 foot, and sheet rocked, as well as painted-
1 prime and 2 finish coats.
Tek track lighting and a few cans (IC) have also been installed.
The duct work is in and installed within the 1 foot dropped ceiling.
My question is:
Is it ok to use open cell soy foam directly over the duct work, and over
sheet rock directly? My carpenter is concerned for the expansion of the foam
over the sheet rock, itself, as well as spraying directly on the installed duck work.
I would save money and be able to use blown in cellulose to a depth
of rough;y 15".

In Energy efficiency and durability | Asked By gary scheft | Jan 27 12
25 Answers

Different SIP thicknesses, different shell types, windows.....

Working on a fun home that will get some solar gains and pretty simple design. We plan to make it future PV adaptable when the costs drop some. Looking at a few wall design concepts.

In Green building techniques | Asked By Jesse Lizer | Jan 20 12
1 Answer

Drywall Vapor Retarding Primer in basement

Hello, I'm finishing the basement paying attention to Joe L's detail: http://www.buildingscience.com/documents/digests/bsd-103-understanding-b...
My drywall contractor suggested vapor retarding primer, before he textures, as this is his standard practice.
Question: should we forego the primer and use only the texture and then latex paint?
thank you

In Green building techniques | Asked By Frank O | Jan 27 12
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