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7 Answers

Review placement and sizing of mini-splits

I have been reviewing the submittal sheets along with what feels like endless reading on this site. Through all the reading and studying I feel like I have a decent sizing and placement locations figured out but would like second opinion.

Front door faces NE and I'm in CZ 4A, 24149. The fireplace is a vented gas fireplace that is vented out the adjacent covered porch roof, no chimney. Patio doors where changed to single doors.

Design temps: 17/89. Indoor temp year round will be set at 72.

Asked By Kevin Lucas | Jan 14 18
8 Answers

What should I replace my heating and cooling system with?

Hi all,

I'm looking for advice on the 'best' solution to my heating and cooling (and hot water)

- Zone 5b
- Loads from coolcalc and manual D/J
Heating loads
- Main house: 28k to 36k, 900 cfm
- Sunroom addition (can be closed off): 8k, 150 cfm unducted not planning to directly heat (current situation)
- Office addition 5k/3k, 180 cfm. Unducted, can probably be heated via staircase.

Cooling:
- Main house cooling load: 24k to 36k, 1200 cfm
- Sunroom addition: 8k, 450 cfm unducted not planning to directly heat (current situation)

Asked By Jill D | Jan 17 18
19 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.

Asked By Jerry Liebler | Jan 15 18
5 Answers

Insulating a walkout basment

I'm trying to insulate my walkout basement in Chicago so Zone 5. I read through bunch of the posts but just need some clarification if what I have gathered is correct. I'm attaching a diagram to show exactly what my plan is but just need to figure out if the section above foundation/ground will have any issues with this setup.

Thanks

Asked By tkaj | Jan 19 18
4 Answers

Insulation with best life expectancy and low embodied energy?

I'm researching insulation options. I want to keep embodied energy down, but also want to have something with a life expectancy of centuries, not decades. Although I've mostly nixed SIPs (PU) because of it's high embodied energy, if it lasts centuries while other insulation materials last decades, then should it be considered? I've also been finding different opinions on the life expectancy of SIPs. Some people say 300 years, others say 50-100.

Asked By Mike AbiEzzi | Jan 19 18
8 Answers

I’m interested in disconnecting from the grid

Our house is tight. One of my big winter loads is the clothes dryer. I am getting questionable reviews on heat pump dryers. Should we just “freeze dry “ laundry on the porch. Are there any options?

We had poor reliability with two different horizontal axis washers and now have a Maytag. It spins but not like a horiz. axis.

Thanks.
Steve in Wellsboro

Asked By Steven McCarthy | Jan 18 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.

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

Asked By Rodrob15 | Jan 18 18
13 Answers

Basement Insulation question

Hi,

I am planning to finish my basement and need help with what materials I should use.
I live in Ohio (5A as per map). I have concrete walls with 8 ft ceiling.

I have been reading a lot and not sure what I should be using. I need good comfortable basement. I was reading best to use XPS but now after reading more I see it is not a green option. I also read there are few new products coming out with HFO blowing agents (where to buy them from or they are not available yet ?) I also looked at roxul comfortboard 80. Please advice.

Asked By bullet0770 | Jan 17 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.

Asked By User-6964558 | Jan 18 18
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