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20 Answers

Another try at a ceiling service cavity framing

I now want the duct ed mini split IDU(s) and ducts within the ceiling therefore what I thought was an economical construction (lattice of flat wise 2x4s) really is not, especially if I'm to have code acceptable ducts. I simply need a taller cavity, 3" isn't enough, 6" is probably minimum. My latest thought is to use a variation of a Larsen truss (2x2 chords and OSB strips on alternating sides forming the "web") installed horizontally. The "Larsen's" top chord is fastened through the upper air barrier material (probably drywall) with screws into the bottom chords of the roof trusses.

In Energy efficiency and durability | Asked By Jerry Liebler | Jan 15 18
3 Answers

Insulation for interior walls

We are in the process of building a “pretty good house” in Manitoba Canada. D.P. Cellulose insulated 12” thick walls, triple pane windows, no gas appliances. Also working hard to limit noise transfer between bedrooms. We have decoupled walls with staggered studs, and framed them either 4”
Or 4.5” wide (bottom plates) with 2x4 studs.

In Energy efficiency and durability | Asked By Scott Benson Climate Zone 7A | Jan 18 18
6 Answers

Perfect Wall assembly

Hello All,

I'm building a small cabin in the mountains of North Carolina later this year (Beech Mountain). Elevation is at about 5,000 feet and the climate can actually be pretty brutal for the southeast in the winter (Zone 5 Climate). Average January high is around 35 and low around 15, but temps can get 10 to 20 below zero on occasion.

I'm planning on building an envelope based on Joe Lstiburek's "Perfect Wall" theory.

My wall will be constructed as follows (from exterior to interior):
- HardiPlank or Galvalume Siding (haven't decided yet) for exterior cladding

In Green building techniques | Asked By Rodrob15 | Jan 18 18
6 Answers

What issues do you see here?

Hi there,

Im building a cost effective shouse in northern British Columbia, living in Zone 7A with 5040 degree-days (no rainscreen or seismic requirements) and planning on building a workshop with dwelling above in the summer.

I need some experienced folks help who have livedin or built similar shops with dwellings to tell me what you would change. I plan on installing a 1.5" concrete topcoat in the suite. Both floors to have hydronic heat. Windows are triple with R8.3 ratings, U 1.02.

In Plans Review | Asked By User-6964558 | Jan 18 18
6 Answers

Bathroom remodel, question on wall construction and shower area

Hello All,

I am currently remodeling a bathroom and need to replace my fiber glass tub and shower surround, i will be replacing it with another fiberglass/acrylic solid surface material but really had the question on how to properly build the walls in the shower area?

I will have a 2' section above and around the the shower and wasnt sure the best way or materials to do this, do i drywall with a moisture resistant product, what about vapor barrier, and air sealing?

Thanks the help and im sure there is more info needed but thought i would start here?

Thank you again

In General questions | Asked By David B | Jan 18 18
4 Answers

Air sealing the rafter-joist intersection on a 1.5-story house

First off, I'm in Zone 3A, Warm Humid, Waterfront Coastal. Design temps are 89 and 29.

I own a 1.5 story that has the usual knee walls and unsealed/poorly insulated rafter-joist intersection.

I've perused many an article on the subject here, including Martin's FHB article http://www.finehomebuilding.com/2012/09/06/two-ways-to-insulate-attic-kn... .

In Energy efficiency and durability | Asked By Bennett G. | Jan 18 18
3 Answers

Vapor retarder/barrier or not?

I am in the process of building a 1400sq.ft. detached garage in Kansas City, MO. I have fiber cement siding, then Tyvek, then OSB attached to 2X4 stud wall 16"OC.

I plan to insulate with Roxul Comfortbatt R-15 after air-sealing every crack and seam with foam and/or caulk. It will get drywall and paint, and will be heated and cooled.

My question is this: Do I need a vapor retarder and/or barrier at all? If so, what type/brand should I use?

Thank you in advance for any help you can offer.

In Energy efficiency and durability | Asked By Adkinsdl | Jan 18 18
6 Answers

Are there benefits or serious drawbacks to using a variable speed air handler with a single speed compressor?

We're restoring a 19th century house in very humid Gulf Coastal climate, similar to New Orleans. We askled HVAC company for variable speed heat pump, and got a quote on a variable speed air handler matched (by the manufacturer) to what appears to be a single stage 14 seer outside unit. I appreciate that there are small benefits to variable speed for heating loads, but don't give a flip about that in our climate.

In Mechanicals | Asked By user-6970120 | Jan 18 18
9 Answers

Insulating a pole barn

Hi. I am interested in building a small (20'x20') eco friendly pole building as a "tiny house". I like the idea of a pole building because it avoids the use of concrete for the foundation. I plan on using perlite bags beneath an earthen floor as the "sub-slab" insulation. For the walls and ceilings, I would like to use cellulose. I have not been able to find any details online for appropriately insulating and air sealing pole buildings. What resources I have found generally ignore thermal bridging entirely, for instance.

I would like to achieve R-40 walls and an R-60 roof.

In Green building techniques | Asked By Steven Gubkin | Sep 30 15
8 Answers

Heat Pump +/- gas furnace

I am building in the mountains of western NC, Zone 4. The bid calls for a Trane 17 SEER, 9.6 HSPF two-stage, variable speed heat pump with a gas furnace backup.The house will be about 4000sf on 2 floors over a crawl, very well insulated, tight, triple pain windows with 10kW of solar. Do you think this is the correct choice for HVAC or is there something better(always considering cost, of course)? Is the gas furnace backup needed?

In Mechanicals | Asked By Kevin Spellman | Jan 17 18
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