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5 Answers

Construction Waste

I often see proponents of different construction methods, like pre-fabrication or SIPS, using the efficiency and reduction of waste as part of the appeal. Can someone explain the rationale behind that claim?
All of the materials I buy, like dimension lumber, sheet goods, pipes, wire etc, are manufactured in certain sizes. Whether I cut them to length on the site or in a shop doesn't alter that. Where are the efficiencies?

In General questions | Asked By Malcolm Taylor | Jun 12 15
3 Answers

SIP OSB panels in contact with raised slab concrete

Our builder decided NOT to use a nailer, and instead placed the SIP panel directly on the 2x4 treated bottom sill plate then nailed the OSB directly into the treated plate. However, the OSB panels, both inside and out sit on the concrete. They did use a closed foam sill seal (blue stuff) so in some cases the OSB is sitting (crushed) on the seal and and many places it is directly on the concrete. Is this a problem? It would seem to us that OSB sitting on concrete or on the thin sealer on concrete would be a problem for the non-treated OSB.

In Green building techniques | Asked By Scott Moore | Jun 14 15
1 Answer

Vented crawlspace insulation in San Francisco Bay area


We are first time home owners, and it is overwhelming. So please bear with me if I get the jargon or naming wrong.

In Energy efficiency and durability | Asked By Vishwanathan Swaminathan | Jun 15 15
2 Answers

My wife and I are beginning the process of building a home in Johnson City, Tennessee

I have been unsuccessful finding a local architect that has ever built a house that uses the green building techniques in design. On the PHI website the state of TN is not even listed on the professionals list. I am surprised that there are not any located in Knoxville. So first question is whether anyone knows of any architects or home performance contractors in the Johnson City area. So far the closest that I have found is Ashville, NC which is only an hour or so away so that is probably workable??

In General questions | Asked By Don Welch | Jun 2 15
4 Answers

Rig an HRV to act as a makeup air unit

I've got some greentec HRV's in my new house.

From what I understand, its possible to change fan speed on the intake/exhaust as to balance the system.

I've seen units like the Best by Broan MD6TU 6" UNIVERSAL MAKE-UP AIR DAMPER what you can put a a sensor in your range hood duct or dryer duct, that if they are activated a flap opens to allow air to directly flow in thereby compensating for the air being removed.

It would be neat if it could be rigged into the HRV that if an appliance like a range hood or dryer is turned on it automatically increases just the intake air.

In Mechanicals | Asked By Mark Helmrich | Jun 12 15
16 Answers

When do desires/requirements compromise any energy efficiency?

For our new house in MN we have some requirements and desires that go somewhat against energy efficiency.

- We need to be able to comfortably host my wife's 40+ person family (lots of brothers & sisters who've produced lots of nieces, one nephew, and now grand nieces and nephews along with our own children and, hopefully one day, grandchildren) and 3 ensuite guest rooms that all add up to a gob of square feet.

In Energy efficiency and durability | Asked By W Ramsay | Jun 11 15
7 Answers

How does the GWP of materials like XPS compare to other activities?

In considering different material choices, global warming potential (GWP) is one of my considerations, among many others. I realize that materials like XPS and closed cell spray foam have many times the GWP of materials like EPS. However, I would like to get a feel for the overall magnitude of the GWP of building material choices relative to other activities in my life, like driving a car. A big percentage change in a small contributor would be no big deal. A big percentage change in a big contributor gets more weight.

In Green products and materials | Asked By Reid Baldwin | Jun 12 15
7 Answers

Varathane over stain...required?

Ok guys. I'm sorry, this is not really a "green" building question, but there is such knowledgable members on this forum I had to ask...I can't seem to find a solid answer anywhere! Plus it deals with VOC's, so thats green based :-)

I have douglas fir 6x6 beam and 1x6 t&g. 50% will be used indoor, 50% will be used outdoor.

We stained the fir with a oil based stain labeled as "interior and exterior". I could not find a water based "exterior" based stain and liked the idea of using the same for all to keep the color matching.

In General questions | Asked By Mark Helmrich | Jun 9 15
3 Answers

Need help choosing ductless HVAC proposal.

I am giving a lot of detail here. I hope the right amount. I'd sure appreciate any help.

In Mechanicals | Asked By DANIEL GOTTSEGEN | Jun 10 15
3 Answers

Is tape permissible between framing and the party wall for air sealing?

We are building a Passive House duplex and have encountered bunch of air leakage around party wall. We don't have to reach Passive House standard for each of the units separately, only as a whole building. But currently, our party wall does not have any air seal crossing between two units. This opens up the possibility of air getting in somewhere at the top end of it (at the roof) and traveling down to edges of the party wall touching the whole building enclosure/exterior plywood. We have difficulty sealing these vertical contact points due to other framing being in the way.

In Building Code Questions | Asked By Lucyna de Barbaro | Jun 12 15
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