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1 Answer

Vapor barrier

Am looking into building ICF homes in another country. My question is they do not generally heat and air condition their homes due to high energy cost. It is warm and humid and am not sure what, if any vapor barrier should be used in the roof area.

In Energy efficiency and durability | Asked By Thomas Webster | Jun 29 16
17 Answers

R-values of ceiling and walls

Zone 5a (on the border of zone 4)
Existing uninsulated concrete slab.
No basement. 2x4 frame.
A bunch of newbie questions.

Why is the insulation recommendation for an attic so much higher than for an cathedral ceiling?
Both are the shell of the building but the attic has an ceiling under it that at least adds some insulation value. I would expect the recommendations to be closer or even reversed.

Many sites stress the importance of a high R-value to save energy.

In General questions | Asked By Tony Tibbar | Jun 3 16
8 Answers

Is a dehumidifier needed in a tight house?

I've read several times that it's common for tight, well-insulated homes to need supplemental dehumidification, as the AC doesn't run enough to dehumidify the home.
As a person who is especially sensitive to humidity, I'm very interested in this.
I wonder if an equal level of comfort can be achieved more economically with a higher temp. set point but lower humidity. (In my case, Chicago area- warm and humid in the summer).

In Mechanicals | Asked By Ben Rush | Jun 27 16
2 Answers

Best practice for extending out a wall


I have a 2nd floor gable end wall which is constructed of (from outside) brick, air gap, block, air gap, 3/4" plaster/blueboard. There is no framing/insulation in the wall. We are converting an existing closet to an opening and to part of the above wall will be furred out with 2x4's. I would like to insulate it while we are in there but as always don't want to create issues.

In General questions | Asked By G S | Jun 29 16
7 Answers

Would IGU windows using laminated glass be the preferred choice to eliminate UV?

I am considering the use of an Insulating Glass unit (IGU) using laminated glass. I assume the laminated glass will be on the interior side. I live in Seattle so air conditioning is needed only 3 months/year. I want low U-factor and high light transmittance (70% is ideal). Also want to kill UV as much as possible. Laminated glass will kill 99% of the UV while some LoE coatings can give 95% but reduces the transmittance to 66%.

Here is a possible configuration using Cardinal Glass:
a) Outboad lite is 3mm glass with LoE270 on surface #2 (and perhaps LoE-x89 on surface #1)

In Energy efficiency and durability | Asked By Mike Chapman | Jun 28 16
17 Answers

Zone 1 home addition — Dual-zone HVAC strategy?

I'm building a 1,700 sq. foot single story addition to my home in Houston, TX. 1,000 sq foot are a woodworking shop, 700 sq feet are living space. Living space is multi-room, think small apartment (kitchen/den, bedroom, bathroom, closet). Shop is one big room with a separate mechanical room. My current HVAC system won't handle the 700 sq feet of living space, which is also on the opposite side of the shop (maybe 100' from the current hot-attic system).

Current house is traditional stick frame, brick veneer with batt insulation and blown-in in attic. Gas available for heat.

In Mechanicals | Asked By Mark McFarlane | Jun 27 16
0 Answers

When is the 'Right' Time to engage a professional (Architect, Consultant, ..)

When is the 'Right' Time to engage a professional ... ?

I'm an aspiring first time contractor of a yet to be designed home on the coast somewhere. I won't be the builder but perhaps I can be actively involved as the General Contractor. I've read much of the material here and at other helpful sites. I've amassed interesting floor plans and designs but I don't have the in-depth knowledge of many experienced people here.

So, when is the right time to seek and engage an Architect, builder, or designer? And, in which order?

In General questions | Asked By JIm Sutton | Jun 29 16
15 Answers

Eastern Canada 'pretty good house' Insulation strategies

I've read so many articles my head is spinning. I'm building in New Brunswick Canada which appears to be equivalent to your climate zone 7. I'm endeavouring to build a pretty good house meaning efficiency to the point of diminishing returns aka maximum value. One of the major challenges I have here is reconciling good building practices I'm reading about here with the capabilities of local contractors. With that said, I have a few questions.

In Energy efficiency and durability | Asked By Barry Reicker | Jun 14 16
3 Answers

5-inch EPS foam

Hello, I am looking to build a 24x30x10 pole barn to use as a shop/ extra garage. I am not planning to use concrete on the flooring just yet because of the cost. Eventually I would like to pour a slab though. I am researching insulation and think I will use a radiant barrier for the roof to under the metal sheets to reflect the roof heat. Actually the siding is metal as well. I was also given (84) used but in great condition 4x8 sheets of 5" eps foam. I am trying to figure the best way to go about it all. Any would be grateful for any suggestions.


In Green building techniques | Asked By Jeramia Johnson | Jun 29 16
6 Answers

Insulating the underside of a concrete deck

I have a 2-story garage project where the lower level is built with ICF walls...R-25....and PEX radiant heated floors with an R-10 underslab insulation but the ceiling consists of the metal concrete pans and +/- 8" of concrete and rebar. Assume that space above is unheated.....it might also get insulated and heated from time to time when the homeowner needs to do automotive work.....but in general it will be unheated.

In Energy efficiency and durability | Asked By Jonathan Scholl | Jun 27 16
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