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7 Answers

Is this a Good Final Envelope Decision?

G'Afternoon! I am a residential designer in Salt Lake City, Utah and after a year of researching sites as FineHomebuilding, GreenBuildingAdvisor & Bldg Science Corp & debating with a client over the pros & cons of various wall envelope options, my client and I have reached the following decision regarding exterior envelope: 9 ft extr walls are 2x6 wood stud at 24" o.c. with spray-in fiberglass cavity insulation/DOW Brand 1" Structural Insulated Sheathing w taped seams/Stucco Finish. Btm & Top plates caulked/sealed & all penetrations foam-sealed. Expected wall R-Value approx 25.

In Energy efficiency and durability | Asked By Timothy Smith | Dec 19 11
15 Answers

Swapping ECM for PSC fan motor

I know a homeowner who runs the fan on his Ruud UBHC-17J11NFD air handler (2.5 ton heat pump) continuously in the summer to help keep the temperature a bit more consistent between the upstairs and downstairs, so he figures swapping the OEM PSC fan motor for an ECM motor, such as the Evergreen, might pay for itself.

The Evergreen mfr/distributor says the following:

In Mechanicals | Asked By charles CAMPBELL | May 11 11
8 Answers

Double Stud Wall in Walk-out Basement

Hello All! I have recently inspected a house that has had a basement renovation completed. The basement was finished with a secondary wall built adjacent to the original foundation/pony wall.
The foundation wall is covered in EPS insulation and appears well detailed with tape and spray foam, as well as being well sealed to the bottom plate of the interior wall and pony wall. The wood framed pony wall has Roxul batt insulation in it. The secondary 2x4 interior wall has nothing in it.

In Green building techniques | Asked By Michael Melo | Dec 15 11
9 Answers

How do I properly seal the underside of an addition built on concrete piers in New England?

I have an existing conditioned space addition that was built on concrete piers in a zone 5, New England climate. The floor structure was insulated with fiberglass and covered with OSB.

The OSB is rotting and the fiberglass insulation is black. All of that material is being removed. What sheathing and insulation materials would you recommend as replacements in this totally exposed floor?

In Energy efficiency and durability | Asked By Ken Shaknites | Dec 19 11
1 Answer

Made in USA video...

Please take a minute to watch this video to the end before you do your next purchase... and then forward to all you know in the industry.
Let's help our industry and our jobs!!!

In General questions | Asked By Armando Cobo | Dec 19 11
25 Answers

Soffit moisture

I built a new house in a suburb of Chicago this past spring and moved in, in August. I had Icynene sprayed in the walls and Gaco firestop 550 on the underside of the roof . Now that we have had some cold weather under 30 degrees I am seeeing moisture dripping from some spots on my exterior soffits and fascia. I had the insulator back to look in the attic, it looks like it was sprayed well and we can't see any areas missing insulation. Any ideas, could humidity be able to pass through the Gaco insulation? Any ideas?

In General questions | Asked By Mike Thornton | Dec 16 11
1 Answer

Tub with shower surround installation

I'm in climate zone #5 (Eastern Washington State) and have framed the house with 2x6 walls on 24"centers,OSB sheathing, WRB, 1.5" foam, 3/4" furring strips and fiber board horizontal siding. The tub/shower surround is on an exterior wall. Information I've seen (JLC Moisture Control, JLC Energy Efficiency and drawings in Strategies & Details) do not show this detail. Without asking specifically about this detail the insulation contractor and bldg dept have indicated that interior poly. is required.

In GBA Pro help | Asked By Thomas LaCrosse | Dec 19 11
0 Answers

To our Romanian readers

The GBA glossary has been translated into Romanian by Alexander Ovsov. Any Romanian speakers who are interested in this new resource will find it here:

Thanks, Alexander!

In General questions | Asked By Martin Holladay | Dec 19 11
80 Answers

HTML hints for Dummies

Hey Dan
Thanks for the New Editing Feature

Use this thread to Practice HTML & Picture posting

In General questions | Asked By John Brooks | Feb 4 10
16 Answers

Building Science .....1911

Check out page 99 in this Radford book from 1911.
Quadruple Glazing, Management of Thermal Bridging...and
Ventilation without motors.
Lots of other good air barrier and water management details thru-out the book.

In Green building techniques | Asked By John Brooks | May 9 09
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