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2 Answers

Furring strips required over 1" rigid foam insulation?

Planning the renovation of a 110 year-old cottage in Indianapolis. Looking to put 1" of rigid foam on the outside before re-siding with fiber cement lapboards, and 3.5" of wet spray cellulose inside. We do have wood sheathing, horizontally hung 1x boards, on the exterior of the wall studs.

Is the furring strip over the foam advisable because it will 1) allow air circulation behind the siding or 2) provide structural support when hanging siding? Or both?

Or, with the relatively narrow foam, is it not required?


In Green building techniques | Asked By William Wagnon | Dec 4 12
4 Answers

Worried about air sealing fireplace attic vent cavity

I'm an insulation contractor and I also try to close up the "big" air sealing holes before we blow in additional loosefill insulation. I want to close off the enormous cavity the builder left for the fireplace vent stack. My concern is how does a fireplace draw fresh air from combustion? Do I need to leave this cavity open to prevent back drafting?
Thank you for your responses.



In Energy efficiency and durability | Asked By Randy Ransom | Dec 3 12
9 Answers

Help me design a small building heating/cooling solution

Hi Folks,
My wife and I have just bought piece of property outside of the Boston, MA area (Zone 5a), and we will be building a home there next year (hopefully...just going through the close process). Currently on the property is an existing structure that I am planning on rehabbing, to use as a detached home office and workshop.

In Mechanicals | Asked By Jonathan Petersen | Dec 3 12
40 Answers

Where does the humidity go in a super-sealed building?

I am wondering deeply, and this question makes me doubt all wall designs.

Where does all the humidity go in a super sealed structure ?

Let's assume that a residential house has an almost perfect water vapor barrier setup
and or is very tight ( my personal example is an ICF house ), what happens to all the daily generated humidity by the occupants ??

I understand that nothing is completely vapor diffusion proofed, but if slow enough,
would the humidity level rise without stopping ?

I am asking this because of the following situation ...

In General questions | Asked By Jin Kazama | Nov 29 12
4 Answers

How to build a waterproof concrete deck over living space?

I would like to build rebuild my front porch about 20' x 9' with a storage room underneath. the porch will have a concrete deck pored over corrugated metal sheets. and the porch is open without a cover.
does anyone know how to spec this the deck has to be 100% waterproof


In General questions | Asked By david reiss | Dec 3 12
8 Answers

How to remove pet odors and stains in wood subfloor?

I would like to know what is a good approach to removing pet odors and stains in the wood subfloor. thanks

In General questions | Asked By louie rodriguez | Dec 1 12
5 Answers

Adding thermal mass to an old wood-frame house

Hi. I'm wondering if there's a way to add thermal mass to the floors and internal walls of an old wood frame house without adding so much weight that it compromises the structure. Ideally, I'd like to add more low SHGC glass on the south side wall of a Southwest oriented bedroom, with sufficient overhang to block direct summer sun, but realize that doing so without adding sufficient thermal mass won't result in good heat capture in the Winter.

In Green building techniques | Asked By Noel Kalenian | Dec 3 12
11 Answers

Can Cardinal LoE 180 be applied to both surface #2 and #3 of an IGU ?

I want to install double glazed replacement windows that have high solar heat gain and a low u value. The Cardinal product for this purpose is LoE 180 applied to surface #3. I would like to have the 180 coating applied to both surface #3 and #2 to further decrease the U value but maintain the high solar heat gain attributes of the IGU. My local Marvin window distributor told me that Marvin told him that 180 could not be used on adjacent surfaces as I am requesting. I have not spoken directly to Cardinal about this.

In Energy efficiency and durability | Asked By Tim Ward | Dec 1 12
1 Answer

What is an energy-efficient refrigerator?

Looking for recommendations for an electric refrigerator to use in a solar-powered (photovoltaic system) house. Will also use a freezer as a separate appliance.

In Energy efficiency and durability | Asked By jula bunkham | Sep 9 12
3 Answers

Will I Have Moisture Problems?

I have learned a lot from this forum and have now started to have concerns regarding my home. Our 1900 sq ft ranch style home was built in 2006 and we had little-to-no awareness of the importance of energy-efficiency and green building. We live in a moderate climate, about 35 miles south of St. Louis, MO.

In Energy efficiency and durability | Asked By Ken French | Dec 1 12
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