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17 Answers

My client would like to purchase a ventless heater to put in his blocked up fireplace

I understand they can run on natural gas, LP gas, or denatured ethanol.
Are these units putting out any substantial heat or are they more decorative?

In General questions | Asked By roger steinbrink | Dec 10 11
1 Answer

How do published commercial and residential code requirements for combinations of continuous insulation and stud cavity insulation relate to in-wall condensation concerns?

The 2012 IECC includes minimum requirements for continuous insulation in combination with stud cavity insulation for wood stud walls. The requirements for these combinations differ between commercial and residential buildings. The required R values for continuous insulation are higher for residential buildings than for commercial. Considering cold climate applications, how do these requirements relate to in-wall condensation concerns?

In Energy efficiency and durability | Asked By Albert Russell | May 13 14
2 Answers

Daily attic air exchanges?

.. with a balanced attic ventilation system in place,

how many attic air exchanges daily should be expected?

In GBA Pro help | Asked By Hans Mayer | May 5 14
1 Answer

What is the level of VOC outgassing from vinyl floor clic planks, please?

How do I find out what level of VOCs are emitted by vinyl clic flooring? And is there a standard to measure this?

In General questions | Asked By marsha merory | May 5 14
1 Answer

Vaulted ceiling assembly

Hi I am looking at building a vaulted ceiling with 11 7/8 I joist 24" oc drywall on the interior, 1/2 osb 4" xps board over osb, and synthetic tar paper on the foam. On top of the tar paper 1x3 or 1x2 furring strips over and parallel to the joist.(to space up the 2x purlins for ventilation and drainage plane) and 2x4 24" oc perpendicular to joist to support a standing seam metal roof. At the eve there will be drip type flashing and 1" thick coravent to ventilate the roof and allow condensation out, there will be a ridge vent on the roof as well.

In Green building techniques | Asked By tobias larsen | May 4 14
3 Answers

Why do monolithic slabs have sloped footers?

Hello. I am attempting to design a monolithic slab for a garage/house project. I have researched monolithic slabs and this is the direction I want to go. But the question is: why, in every drawing and implementation of a monolithic slab, is the inner wall of the footer sloped toward the middle of the slab? Why not just a straight footer? Does this have to do with stress cracks and a better joint between footer and slab, or does it save concrete, etc? Thanks for any info!

In General questions | Asked By Ryan Griggs | May 12 14
1 Answer

Insulating a vaulted ceiling with limited room for insulation

I have an older house which has a vaulted ceiling. I am planning on re-insulating this ceiling from the inside. I have removed the existing ceiling and insulation. The roof is 2x6 rafters, so I have limited space within the bays for insulation. I am not opposed to adding foam board to the bottom of the rafters. I plan on putting pine v-groove tongue and groove boards up for the finish ceiling. I am looking for some recommendations on what products to use and how to best install them.

In Energy efficiency and durability | Asked By Bill Chiari | May 12 14
7 Answers

Techniques/materials to improve the air-tightness of a 1920s-era bungalow in a hot & humid climate (Zone 2A)?


In Green building techniques | Asked By Robert Hallenbeck | May 11 14
6 Answers

Soy vs. cellulose

Which is less toxic? R factors are the same for open cell?

In General questions | Asked By LAURA ASHLOCK | May 10 14
3 Answers

Exterior Below Grade Spray Foam


I'm curious what the group thinks about exterior below grade spray foam. The current proposed basement insulation solution is to apply 3" of Closed Cell Spray Foam directly to the exterior of the poured concrete foundation wall. The foam will be protected with drainage mat prior to back filling.


In Energy efficiency and durability | Asked By Howard Road | May 8 14
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