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4 Answers

Using nailbase panels as wall sheathing

I'm considering framing a large addition with 2x4 studs (actually, engineered studs) 24" OC with open cell spray foam in the cavity, with a exterior application of 2" nailbase (1 1/2" foam with OSB sheathing attached). My question is whether the nailbase will serve the lateral bracing function of typical sheathing, given that it will be separated by the 1 1/2" of foam to the studs. In other words, can I just use nailbase without adding a redundant layer of sheathing directly applied to the studs?

In General questions | Asked By David Hornsteing | Oct 9 15
12 Answers

Below grade XPS placement, protection, and detailing

I'm pouring a traditional 8" concrete foundation for a client this week. They planned to have us place 2" of XPS foam on the outside of the walls for insulation. Once they can afford to finish the basement, they would place another 2" of foam on the inside of the walls between treated 2x2s and sheetrock over it for the finished assembly.

I've attached a rough sketch of the various components.

In Plans Review | Asked By Nethaniel Ealy | Sep 16 15
3 Answers

Need help selecting MassSave cellulose densepack contractor

I know bunch of you are here from MA, so I figured I should ask here.
Contractor, that did insulation work on my house last year is no longer in MassSave program. One they recommended is booked literally into late spring and won't take on new bookings.

So now I need to find a contractor to pack my empty walls (clapboard siding). Any recommendation for solid contractor who can do the job in Waltham area? List is like 100 contractors long, so it is hard to pick.


In GBA Pro help | Asked By Apollo S | Oct 7 15
2 Answers

MItsubishi or Fujitsu, dual or single

I am renovating an 800 sq/ft Shotgun style house. I have had icenyne spray foam insulation sprayed throughout; ext. walls, attic, and crawlspace are all sealed. I am trying to decide what to do with hvac and am looking into mini splits. I prefer the ceiling cassette unit for looks. I am in the Louisville, KY area. The floor plan is mostly open with the living room/kitchen being one zone and the bathroom, bedrooms and utility room being separated with two doors.

In Energy efficiency and durability | Asked By Erich Popp | Oct 9 15
12 Answers

Mini-split + heat pump water heater OR geothermal cool/heat + water heating?

Dear All,
I have read a number of articles on this forum and most seem to favor ductless mini-splits over geothermal. I believe peopel have said performance may be neck and neck while up front costs probably favor the mini-split.

However, what happens when water heating enters the equation? Some background:

In Energy efficiency and durability | Asked By Gina Jasso | Oct 4 15
4 Answers

Venting an existing flat roof

We have a row house in Chicago. The drawing indicate (it seems it was built as drawn) that we have a 1/4" per foot modified bitumen roof. We don't have soffits or ridges (just parapets on three sides and a gutter along the back). The roof structure is min 16" wood roof trusses at the low gutter end and they get bigger at the front. We have R49 Green Fiber blown in cellulose insulation in the trusses. There is no vapor barrier (as the insulation suggested) and there is two layers of 5/8" drywall at the ceiling. We have mushroom vents at 1 sq. ft. of net free area for every 300 sq. ft.

In Building Code Questions | Asked By Trisha Megan | Oct 8 15
3 Answers

Fantech MUAS

Is anyone familiar with this product/strategy? We are working on a custom home in Louisiana and are interested in utilizing it. We discussed a make-up air for the range hood when the fireplace damper is open, and we're thinking that this might be a good solution. I'd appreciate your feedback. Thanks!

In Mechanicals | Asked By Heather Gayle Holdridge | Oct 9 15
22 Answers

Insulating plumbing vents and drains?

Is it worth the expense and time to insulate drains and vents? Essentially they are outdoor spaces inside your envelope? Just trying to decide before closing up some walls.

In Green building techniques | Asked By Lance C | Sep 10 15
9 Answers

How to use water for thermal mass

I have a room in the basement that has a large south-facing window. We don't really use this room but it would be nice to use the solar heat that collects in there to warm the basement. What is the cheapest way to use water as thermal mass? If tubes are the answer, what kind of tubes? If a barrel, what color? Can I use black plastic 55-gallon drums? Thanks for you help!

In Green building techniques | Asked By Beth Sorrell | Dec 13 10
6 Answers

Insulation type, etc.

hi all,

i have a semi-detached brick 2-family home in brooklyn. 20' x 65'. tenants are on the top floor and we occupy the first 2 floors. our ground floor is about 3 feet in ground on 3 sides and at grade in the rear. we are renovating and intend to put 2 full bathrooms and 3 bedrooms there, in addition to the laundry and utility room. we recently install a navian ncb240 which currently serves our dhw and baseboard radiators for both floors (tenants have separate boiler).

In Energy efficiency and durability | Asked By Josh Millis | Oct 1 15
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