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1 Answer

ERV - Sizing and location with wood stove?

With the tremendous assistance from all you folks, my Bozeman MT historic bungalow replica is well underway, my son and I have got the framing completed, the roof is on and the drain, waste, and vent are installed. It sits on a basement that equals the first living floor of 1,300 sq. ft., and then the two bedrooms upstairs add another 750 sq. ft. The air here is arid, can be hot in the summer an for a couple of weeks, damn cold in the winter. Due to the roof orientation, I've only been able to do a solar hot water system vs. solar electric.

In Mechanicals | Asked By Brian Martin | Sep 16 15
4 Answers

HVAC filter MERV ratings vs pressure drop

Heat pump (GSHP)---- system rated for a MERV 11 filter with a 2 speed compressor and motor -----
I want to temporarily (during construction completion) install a filter at the return grille in the ceiling (to keep any potential dust out of the return ducts) in addition to the normal filter at the AHU.
1) Are there adverse effects to doing this?
2) What combination of filter MERV ratings could I use so there aren't any adverse affects?
a) How about MERV 8 at both locations.
b) How about MERV 2 at the ceiling and MERV 8 at the AHU?

In General questions | Asked By john walls | Sep 16 15
10 Answers

Sheathing questions for tiny house on wheels - help!

I am planning on sheathing both the walls and the roof of my tiny house on wheels this weekend (subject to hurricane force winds while driving down the road). I have several questions about sheathing that I can't seem to find clear answers to anywhere:

In General questions | Asked By Ryan Reed | Sep 15 15
11 Answers

Mixed-humid climate construction details

I am in the planning phase of building a home in Knoxville, TN (Zone 4). I have spent a ton of time reading material on this site and have come up with a preliminary plan that I have discussed with several custom home builders.

Brick cladding (areas with stone gables)
Air gap
1 1/2" Polyiso (foil out)
Taped and sealed OSB sheathing
2X4 Wall cavities filled with damp spray cellulose
Gypsum board

ADA ceiling with 5/8" drywall (minimize or eliminate can lights)
Blown cellulose insulation to depth to provide 2015 IRC Code R-value (flat ceilings)

In General questions | Asked By Rob R | Sep 14 15
5 Answers

Crushed rock or plumbing rough-ins first?

New construction, Superior Walls & slab on grade (daylight on 3 sides, against an upslope bank).

After leveling and compaction, the excavator will provide 8" of crushed stone leveled and compacted for both the Superior Walls (first), then the slab that will be poured to them.

In GBA Pro help | Asked By David McNeely | Sep 15 15
1 Answer

Dealing with a vented crawl space

Our home was built in the late 60s and sits on a vented crawl space in the Southeast. The crawl space is about 1800 square feet and actually has only 3 block size vents. So there is really not much ventilation currently. There is a vapor barrier installed on the dirt floor but there are many gaps and it is your basic 6 mil plastic.

There are signs of "wet block" in certain areas of the crawl. One issue that I may have is poor grading in certain spots of the house that is allowing water to collect.

In Energy efficiency and durability | Asked By Patrick Cox | Sep 16 15
9 Answers

How to heat small first floor rooms?

I am building an addition with two rooms above a garage in Vermont that will be too far from my otherwise open first floor to get sufficient heat from my current wood stove or a possible mini-split that would be centrally located. I might use the air conditioner about three hours per year -- it seldom gets hot here so that is not part of my calculations.

What are good options for a heat load that often might be only 3K BTU/hour? So far I have not found the ideal heating solution:

In Energy efficiency and durability | Asked By David Martin | Sep 13 15
5 Answers

Has anyone used R-sheathing with Thermawrap R5?

I'm working with a builder to build my house in Zone 6. We are trying to get a nice, tight, well insulated envelope, but going back and forth on approaches that could work. My builder has been concerned about the cost of double stud, 2x6 with 2" rigid foam, etc. The latest suggestion is to use Roxul in the 2x6 cavity, R-sheathing, then Thermawrap R5 outside of that. Anyone use these two products together? I'm concerned with moisture in the walls, and I'm not sure what to suggest next to keep costs down, but keep the quality of wall assembly up. Any suggestions helpful!

In Green building techniques | Asked By Bethany Walsh | Sep 14 15
1 Answer

Will two-sided foil-faced polyiso cause an issue?

Well my house is nearing completion and we are about to add the foam and siding. I've been shopping reclaimed foam and was able to get a nice deal on 3" polyiso in perfect condition the only issue is it has the foil face on both sides. I was wondering if I would have any issues using this foam on the exterior. My buildout from inside to out is as follows:

1/2 Gypsum
2x6 16" OC with dense packed cellulose
1/2 Zip Sheathing
Tyvek Drainwrap?
Foam either poly or xps (taped)
1x4 rainscreen
LP Smartside

In Energy efficiency and durability | Asked By Arthur Ledoux | Sep 15 15
6 Answers

Insulate crawl space floor?

We are building a single story home in zone 6B (West Central mountains of Idaho) and the framers are scheduled to arrive Monday 9/14. We are using a sealed, conditioned crawl space, but I haven't seen any details that included insulating the floor of the crawl (bare dirt in this case). Our stem walls (30" tall on top of 10" tall footings) and rim joists will be insulated, likely with spray closed cell foam. One of the framers I interviewed thought I should really consider insulating the floor as well, as the ground temperature will be stealing heat from the home.

In Energy efficiency and durability | Asked By Philip Joyal | Sep 12 15
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