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1 Answer

We’re looking at 10 yr old tract houses to remodel and live in. But we hate the cathedralized ceilings which show up even in houses of 1700 s.f. -- a local builder fad at the time. First, I know cathedrals aren’t good for energy efficiency with 4-6” of glass batts and no air sealing. Second, they may look grand in a big house but in a small living room or 12x12 bedroom they feel like an elevator shaft. We don’t like them … but the houses are cheap enough to think about.

In Green building techniques | Asked By JoeW N GA Zone 3A | Oct 10 11
7 Answers

We have purchased a 100yr old home in central Massachusetts with a stone foundation. The basement is used solely for the purpose of holding the heating and hot water systems. We are in the process of addressing significant water problems. To date we have installed sump pumps, air exchange ventilation system, dehumidifer and we have begun parging the stone walls with hydraulic cement. Long term plans are to regrade the exterior and divert roof water away from the building. That being said we believe the basement will never be entirely dry and the cost to do so is prohibitive.

In GBA Pro help | Asked By Michael Peluso | Oct 9 11
2 Answers

I am a HERS rater and EE building consultant. 40-50% of the new constructon I see utilizes an ERV/HRV for whole house ventilation. Of those, (roughly) half of those are installed in houses using ductwork for space heating and/or cooling. Of those many have the ERV/HRV houseside ports ducted into the return side of the duct. My question is: How reliable is the airflow strength of the ERV/HRV when the ERV is called to run, but the air handler unit fan is not running.

In GBA Pro help | Asked By Kevin Hanlon | Oct 7 11
2 Answers

I'm doing a number of highly insulated retrofit projects, and am concerned about long-term moisture in wall and ceiling cavities. I've had a brief intro to WUFI, the hygrothermic analysis tool, and am using v.5.1 (non-commercial) on my projects. But there are some inputs on the Surface Transfer Coefficient page that make a big difference in performance, but aren't intuitive or explained. They are:

-Short-wave Radiation Absorptivity (should we use "no absorption" or try to use the closest value?)

In Energy efficiency and durability | Asked By Tom Bassett-Dilley | Oct 7 11
3 Answers

It is an open overhang, so no soffit. Black roof. The mold is on the back side of 3/4" exterior plywood which replaced original 80 year old deck 11 years ago. This playwood was painted with oil based Sikkens Rubbol DEK. This mold is occurring on all orientations of the house. It is a gambrel roof, dutch colonial style. A detached garage with the same style overhang has the original wood deck and has no mold. I originally thought that the sun was driving water vapor slowly through the shingles, wood deck and it condensed on the back side.

In Energy efficiency and durability | Asked By mark faultersack | Sep 28 11
4 Answers

Our firm is developing a range of sustainable wall section details for our clients to select from. For several variations, we have 4" of rigid polyisocyanurate foam outside the structure. Along the walls, screws through 1x4 strapping fix the foam back to the studs. At the corners, however, this becomes difficult. What do you suggest? Any clarification would be helpful.

In Green building techniques | Asked By Samuel Ganton | Oct 6 11
7 Answers

I got another email from one of the GBAGreenBuildingAdvisor.com regulars asking if I could change the comment settings to display the newest comment at the top rather than the oldest comment at the top of the thread.

After clicking a few boxes, i discovered that yes, I can change that fairly easily.

I suspect that some people will be unhappy with this, so I'm going to take a poll:

In General questions | Asked By Daniel Morrison | Sep 30 11
6 Answers

Our county is considering creating a Energy Efficiency requirement of a HERS 70 on all new residential construction. If we follow the IECC 2009, which our state has adopted, the prescriptive path is presumed to achieve a HERS index of 89. The question posed is how much more it will cost a builder, including HERS analysis, testing, and verification, to get to a 70.

In Building Code Questions | Asked By kim shanahan | Oct 5 11
3 Answers

We are working with a couple customers that are primarily concerned with effective heating...They want to be able to stay comfortably warm. We have recommended the air sealing but they get cold easily and need a steady reliable & preferably green source of heat. They only have electric available so gas is not likely to be a good option. They currently have a combination of radiant ceiling heat and some cheap wall heaters.
Heat pumps don't work well when they want the heat the most...
Any experience with electric radiators? Other suggestions?

In General questions | Asked By Kent Mitchell | Oct 6 11
11 Answers

I was just asked again today... "What is the best way to build the envelope of a home?" I know the real answer is "it depends" and then we could launch into the hundreds of different techniques. I feel the green building community, however, needs to provide an answer that applies to 90% of all homes. This shouldn't be that hard as 90% of all homes are built the same way now...stud walls, OSB sheathing, house wrap, some kind of siding, and batt/blown insulation.

In Green building techniques | Asked By Andrew Homoly | Oct 4 11
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