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4 Answers

Difficult building inspector

Needless to say our Building Inspector is real charmer, and on top of that is very unfamiliar with energy smart building techniques. We are putting up 3" of Roxul comfortboard followed by 1x4 furring strips and Hardiplank fiber cement siding. The inspector wants proof from James Hardie that this method is acceptable and safe. We sent him this document from Roxul where they had Building Science Corp conduct a study on deflection using our exact cladding system.


In Building Code Questions | Asked By Brian W | Nov 21 16
4 Answers

Insulating a timber-frame building with cellulose — moisture issues?

Hi all, thanks for all the great information here...I really appreciate it.

We're in the process of building a timber frame workshop & office. Only one of the "bays" will be insulated and heated...a 12'x24' space, with a 9' ceiling. There will be insulation directly above the ceiling, and then storage space above that. Below the frame is a root cellar, separated by 8" joists. Basically we are making an insulated, conditioned cube within a section of the frame.

Right now I am thinking of doing the following:


In Energy efficiency and durability | Asked By Taylor Burt | Nov 20 16
6 Answers

Engineered hardwood floor in basement

We have purchased engineered wood flooring for our basement. We are are also installing it on the main level. We wanted to avoid vinyl flooring and carpet due to chemical sensitivities; tile wasn't in budget; and due to height requirements on the stairs, unfinished concrete wouldn't work. Our original installer planned to glue down with Dritac Golden Bullet 4141. Unfortunately, that installer no longer has time for our job and we are getting a lot of resistance from other installers about glue down.

In Green building techniques | Asked By Carolyn Farrow | Nov 21 16
1 Answer

Update on energy modeling software recommendation?

I know Martin wrote about the various energy modeling programs and their limitations back in 2013. I think BEOpt was relatively new at that time. I'm interested in knowing how people are liking it compared to other simple, free programs for use during the design phase. For instance, what would be most useful for an architect wanting to incorporate energy modeling into her typical design process, including for clients for whom energy efficiency is on the list of priorities, but not necessarily at the top?

In Green building techniques | Asked By Hallie Bowie | Nov 21 16
6 Answers

I have recently completed my new home. I was successful in making it air tight. Now I need controlled ventilation.

I have a commercial range. The pilot lights give off enough CO to set of the CO detectors after 18 hrs. I have a vent hood with make up air but of course this does not run when the range is off. The home air is also stale. I want to install an HRV. From an energy efficiency standpoint would i be better off to install a stand alone unit or one that ties to my air handler. I live in Wyoming and the home is 2300 sq. ft.. Thank you in advance for the advise.

In Mechanicals | Asked By Charles Cloud | Nov 21 16
5 Answers

How should I insulate this roof assembly?

I am building a 24' x 8.5' "tiny house on wheels." The roof is pitched at 3.2 degrees and is sloped the long direction (perpendicular to the rafters). So as far as insulating it is concerned, it is essentially a flat roof. The rafters are 2x6. Sheathing is 1/2" plywood, and the roof will be covered with ice and water and a low-slope metal roofing.

My original plan was to spray foam the whole assembly (closed cell) and leave it unvented. Now I am rethinking this due to the expense and possible health concerns with foam (or at least improperly installed foam).

In Green building techniques | Asked By Mike Spooner | Nov 20 16
7 Answers

How low is too low for indoor humidity?

So you guys have answered numerous questions about humidity for me during the summer. I have a 20 year old two story house that we bought this year and promptly bought two new HVAC 5 ton units and put open cell foam in the attic and encapsulated and foamed the crawlspace. The attic has a couple of supply vents and the crawl has four supply vents and a return. My question is about the low humidity I am now getting now that it is finally getting cold in Nashville.

In Energy efficiency and durability | Asked By John Sexton | Nov 20 16
3 Answers

Is it worth it to add more attic insulation on top of R-40?

My house was built in 1989, the attic originally had fiberglass batts with loose fill rock wool. A couple of years ago cellulose was added to bring the overall R value to about 40 (hard to calculate exactly because the weight of cellulose also compressed whatever that's beneath it). Now with $300 I can add 4 more inches of cellulose to bring it to about R50. Is it worth the cost?

In General questions | Asked By Joe Blanco | Nov 20 16
13 Answers

Insulation on exterior and interior

My house was built in 2009 in climate zone 6. It has a poured concrete foundation with R-5 XPS exterior insulation. Currently there is no insulation on the inside.

I am planning on finishing my basement and am curious on what the best way to insulate the interior would be. I spoke with my city inspection department and got some conflicting information on energy code compliance. One inspector advised not to add any additional insulation and the other advised 1"XPS with a 2x4 uninsulated studwall was sufficient but the XPS was not totally necessary.

In Building Code Questions | Asked By Nick Collins | Nov 14 16
2 Answers

I need advice about a new central heating system

I have to replace our central heating system within the next year or so. We live in a gas-heated wood-framed 3-story colonial with 4 zones, built in 1987 in eastern MA, located on the water.

We have no central AC but want to install AC. Tankless hot water is appealing though our water tank is new.

Please advise if possible. I am investigating Navien, Burnham, Lochinvar, Viessman.

-- Ann Tauro

In Mechanicals | Asked By Ann Tauro | Nov 21 16
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