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7 Answers

Interior vs. exterior air barrier

Wondering what the consensus is on the interior vs. exterior air barrier issue is? I am considering this question in light of a double-stud, dense-pack cellulose wall.

Marc Rosenbaum has indicated that he prefers exterior air barriers, because they are so much simpler to execute (no zig-zagging around floor systems, etc).

In Energy efficiency and durability | Asked By Burke Stoller | May 4 16
1 Answer

Insulating two crawl spaces

A friend is having some work done on his old house in upstate New York, Climate Zone 5/6. There are two crawlspace issues.

In Energy efficiency and durability | Asked By Chris Ermides | May 4 16
1 Answer

Townhouse common wall upgrades

I had a kitchen fire in my Gaithersburg, Maryland townhouse (about 20 miles north of Washington DC). The insurance is going to pay to have the walls on the first floor removed and have the insulation replaced. The townhouse was built as part of a quad in 1986, with the main wall facing south, and east and west walls connected to neighbors, and half of my northern wall is connected to my neighbor behind me (the other half faces the central atrium).

In Building Code Questions | Asked By Carl Fosler | May 5 16
7 Answers

Preparing for future solar panels

Building a new home and want to install solar panels at some point in the future. They won't be in the budget initially, when the house is built, but I want to prepare for them and make sure I don't miss something during the construction process that I will have to redo.

The panels will not go on the roof, they will go out in the yard or on an outbuilding or pergola, so I don't have to worry about running wires from the roof to the basement. However, do I need a particular type of breaker panel? Do I need to spec certain equipment?

In Green building techniques | Asked By Clay Whitenack | Apr 25 16
6 Answers

Photovoltaics: String vs. Microinverters

CZ-4. Southern Indiana. New Construction Ranch. Garage Roof faces 30 deg west of south (210 deg). NO shading from trees now or in future. About 36 Grid-Tied Panels. No battery back-up. A purchase arrangement, not a lease type transaction. Three major installers in the metropolitan Louisville, KY market.

Two competing PV installers. One for Microinverters ; one for Strings with single inverter/optimizer.

In Energy efficiency and durability | Asked By Ted Cummings | Apr 30 16
6 Answers

Paint as an Air Barrier

CZ-4. Net Zero Energy Slab-On-Grade Ranch. Planning for 0.1ACH50. Huber Zip-R sheathing.

In Green building techniques | Asked By Ted Cummings | May 2 16
6 Answers

Is this my best foundation choice?

First off, Green Building Advisor has been invaluable in my research to design my future home and have found it well worth the membership cost. So thank you, to all you who have made this site what it is.

I am planning on building a 1700 sq ft ranch style straw bale house near Cortez Co (climate zone 5B). Currently I am sketching up layouts, making lots of notes on building techniques, choosing home fixtures (doors/windows), HVAC systems and researching different build options, before I take my plans to an architect so he can refine and incorporate them.

In Plans Review | Asked By Ken Hodge | Apr 29 16
1 Answer

A temporary situation for new people registering on GBA

As our I.T. team tries to find a good way to block Chinese companies which have been flooding our site with spam, we need to temporarily stop accepting new registrations for the GBA site. (I'm talking about the free registration that is necessary before you can post a question or post a comment.)

We anticipate that this situation will only last for a few days. Once we get a handle on a way to fix the spam problem, the site will once again accept new registrations.

Anyone who wants to become a GBA subscriber can still subscribe at any time.

In General questions | Asked By Martin Holladay | May 2 16
8 Answers

Economical, Long-Lasting, Flexible Sealant

CZ-4. Net Zero Energy Home. New Construction Ranch . Concrete Slab-On-Grade. Planning for 0.1ACH50. Using Huber Zip-R panels with (1"PolyIso laminated to the OSB).

In Green building techniques | Asked By Ted Cummings | May 2 16
1 Answer

Drain penetrations in a slab on grade

Hi, we are pouring a 5" floating slab on grade with several cast iron drains penetrating through the slab.

the drain lines run in the compacted fill below the 4-6" compacted gravel, 6mil vapor barrier, 2" tongue and groove xps and the 5" 4000psi pour with 1/2 radiant pex throughout.

the assembly we are planning on was to cut a hole in the vapor barrier and attatch to the cast iron pipe with tape, then cut a hole in the insulation around the pipe and fill with spray foam and finally to wrap the segment of the pipe that would be in contact with the concrete with thin foam insulation..

In General questions | Asked By Big Ern | May 2 16
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