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3 Answers

Cost to install exterior foam or Roxul?

I am curious about what the installation labour costs are for exterior insulation boards - foam or Roxul. For comparison, lets just say one layer that does not include taping or caulking. Does anyone have a cost per square foot of wall or floor area that they charge or have paid?

In Energy efficiency and durability | Asked By Patrick Walshe | Feb 20 13
6 Answers

EVR Systems

We have a newly constructed 2,600 sq. ft. home in San Angelo Texas area.
Home has 5 Ton & 2.5 Ton 16 Seer Train Units.
Home has Spray Foam Insulation at 6" Exterior Stud Walls and underside of Metal Roof.
Home has FMI Wood Burning Fire Place with Damper & Freshe Air Lever.
We are getting smoke in the house from the fireplace.
Occurs when we open the front door which is adjacent to the fireplace.
We are being told the house is to tight and we need a EVR Unit??
Please advise.

In Mechanicals | Asked By Ron Fallin | Feb 20 13
10 Answers

Indirect Water Heater Vs. Electric Resistance Preheater

Quick question regarding overall efficiency.

My incoming domestic water is around 40 degrees F and my boiler is unable to heat it up to a temperature that is warm enough for showers. I was thinking of two options.

1. Installing a electric resistance 30 gallon preheater. This would preheat the incoming water to around 60 degrees or so before it was fed into the boiler to bring it upto temp for showers.

2. Install an indirect hot water heater tank.

In General questions | Asked By Kevin Lauscher | Feb 19 13
7 Answers

Is sheathing a metal roof necessary?

I'm a carpenter here in Asheville,NC zone 4/5 and trying to design a home for myself so I need to make it as inexpensive and green as possible. I'm thinking of a shed roof using flat trusses with blown cellulose to R-60 and a metal roof. Of coarse, there will be eave and "ridge" vents. So do I need to sheath the roof for metal or will just using purl-ins work. My main concern in condensation. If you dont think this would work could you suggest other systems that would be inexpensive labor is less an issue since I will be doing most of the work myself.

In Energy efficiency and durability | Asked By terrell whitworth | Feb 20 13
1 Answer

How close together can radon and plumbing vents be?

In new construction, I am sending my radon and sanitary vents up to the roof side by side in the same chase. Is there a code requirement that their outlets be separated by 10 feet? That would make sense, but also be quite inconvenient. The concept of actually joining them below the roof deck and having a single penetration has already been rejected on GBA (for obvious reasons, but I'm glad someone else asked the question; I had been wondering about that too.) It seems the same logic would have the vents be separated by more than a few inches.

I appreciate any guidance!

In Building Code Questions | Asked By Andy Chappell-Dick | Feb 21 13
1 Answer

Exterior door thresholds on slab-on-grade

I'm currently sort of scratching my head over this.

When using under slab rigid insulation and the slab is floating over the footing wall.

Typical details calls for 1" rigid between the slab and the concrete foundation wall as a bond break.

Fig 1 from Buildingscience.com.

Now what happens at entry door thresholds (or floor to ceiling windows)?

Extending a lip from the slab towards the outside (effectively eliminating the 1" joint) would cause thermal bridging, so that's out of the question.

In Green building techniques | Asked By SULLKA LIMA | Feb 20 13
10 Answers

Do I have to clean out and replace the Great Stuff?

I have been back-side and edge sealing and also sealing the gaps on the inside of electrical boxes with Great Stuff Door and Window (low expansion foam). Then today I saw a blog that says Dow advises not to contact it with copper wire. I called them and they said its flammable during installation and when cured.

Do I have to clean out the Great Stuff and switch to another product for air sealing electrical boxes? If so, any suggestions.

Thanks in advance

In General questions | Asked By Oak Orchard | Feb 15 13
8 Answers

Insulating a strapped attic floor

Need to insulate an attic floor with 24oc/12in high truss joists that have been strapped with 1x3 strapping, 16 oc across the underneath of the joists. 1/2 blue board is attached under the strapping and veneer plaster makes up the ceiling. 2 coats of Behr ceiling paint is on the plaster.

In Energy efficiency and durability | Asked By stephen edge | Feb 19 13
2 Answers

Insulating a void in basement.


I was wondering if the experts here could help me with an insulation question.

I have a fireplace in the basement that we do not ever use. It is a slight bumpout from the house. There is a bathroom just above it on the first floor (the chimney angles up to the left and does not interfere with the bathroom). As a result, there is a void above and behind the fireplace and below the 1st floor bathroom (roughly 40 inches to the foundation wall).

In Energy efficiency and durability | Asked By Allan Wood | Feb 18 13
5 Answers

What type of insulation and how much insulation should I use between ceiling joists in garage?

I live in zone 5 in northern New Mexico and live in an apartment above a 3 bay garage. The ceiling joists in the garage are 2x12 on 12" c/c. The only heat source for the upstairs is from a small wood stove. I need to insulate the ceiling of the garage below. The garage walls have no insulation. What type of insulation and how much insulation should I use between ceiling joists in garage? Also I would need to insulate the rim joists.

In Energy efficiency and durability | Asked By James DeCastro | Feb 19 13
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