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0 Answers

Connecting ICF Foundation Wall + Timber Frame / SIP?

I'm planning to build a timber frame home soon (eastern white pine and SIPs) and have received a decent quote for an ICF basement.

I like the idea of efficiency in this combination and know that others have built this way but am a bit confused about how they connect? We are responsible for the foundation and first floor decking before the timbers arrive.

Does any one have construction details they could share for this (ICF wall, sill plate, first floor deck, post, blocking, and SIP positioning)? If not can any of you share your experiences with this?

Asked By Jeremy Mayhew | Mar 3 15
8 Answers

Dana, others, DIY PV, mini split, superinsulate, costs

What would it cost today to roof install 5.6KW of PV DIY?

DIYers are eligible for what rebates in NY in 2015?

Anyone?

Martin a blog on DIY PV and DIY mini split installation?

5,6KW PV for $2/W? $11,200?

DIY 2 ton mini split two heads, $1800x2= $3,600?

Superinsulate a 1,800sqft home, DIY cellulose purchase, 12" walls, 30" lid, $5.000?

These items can be done by one timers, DIYers.

Be nice to have a Q&A with this information on costs all in one thread.
Thanks
aj

Asked By aj builder, Upstate NY Zone 6a | Mar 2 15
3 Answers

Sealed crawl with passive exhaust?

I work with a non-profit building small, affordable houses in climate zone 4A. We have tried a few different methods of sealed/ conditioned crawls, but I am interested in finding the best, inexpensive method that will work long term for our buyers. So it needs to require minimal to zero maintenance or understanding of the science behind it for the people living in the house.

Asked By Emily Lingerfelt | Mar 3 15
5 Answers

Calculating break-even point when mini-split costs same as running boiler

I have original steam boiler that is maybe 75% efficient (it is converted to gas 10-year old boiler). Recently, because we wanted AC, we installed air-source heat pumps (Mitsubishi MXZ-2B20NA with MSZ-GE06NA and MSZ-GE09NA head units). Basically one heat pump has one 6K and one 9K heads.

I am located in Boston. COP of Mitsu I calculated at 2.6 since HSPF is 8.9.

So what I am struggling to figure out is at which outdoor temperature it makes sense to switch from boiler, that costs $1.5 per therm at current New England prices, to mini-splits at current $0.243 per KWh.

Asked By Apollo S | Mar 2 15
12 Answers

Adding wall R-value in a historic retrofit

What options are available for adding r-value to a wall if we can't remove the exterior siding? I see three options...
1) dense pack cellulose in the existing 4" wall cavities (~R 14-16)
2) Closed cell spray foam in existing 4" cavity (~R 26-28)
3) Add a double interior wall filled with 7.5" of dense pack cellulose (~R 26-28)

Asked By alok khuntia | Feb 28 15
10 Answers

Biggest bang for your buck?

We are about to begin construction of a new home near coastal Connecticut. We are trying to incorporate green approaches where feasible. Three main components are: Insulation; energy source (ie Geothermal); and energy distribution (ie in-floor radiant heat or forced air). Of these three green approaches, how would you rank them in terms of biggest bang for yurt buck, assuming you can't afford all three. Thanks!

Asked By Justin Murphy | Mar 1 15
1 Answer

Floor construction for a finished basement

I have a basement with 7 feet of unfinished clearance, floor to joist. The basement floor and walls are poured with no subslab insulation. The current plan for the floor is to put down a layer of poly, followed by 1 inch of XPS and then 1/2 or 3/4 plywood. The plywood will then be painted or otherwise finished. I'll finish the ceiling using flush-mounted wood or drywall panels between joists. This is all assuming I can get a 2-inch variance on the headroom (i.e., can get away with a 6'10" finished ceiling). Increasing the unfinished headroom is not in the budget.

Asked By Andy Martin | Mar 3 15
16 Answers

Do screws through exterior insulation reduce the wall R-value?

I was in a Net Zero Building class this weekend and there was mention that screws that are used to attached exterior insulation reduce the whole wall R-value by 39%.

The screws are attached from the outside thru the rainscreen, insulation, WRB, sheathing and into the framing.

This individual referred to an article from Energy Design Update (no issue was noted). I'd check but $600.00 for a subscription is too rich for my pockets.....

Any help here on the article or data at least, with other references?

Asked By brad hardie | Mar 1 15
2 Answers

Should engineered wood flooring be glued to a concrete slab?

The builder wants to glue engineered wood flooring onto a new concrete floor, over a primer. Is this wise?

Asked By Christina Griffin | Mar 2 15
8 Answers

Trombe wall (non-vented) with exterior moveable mode of insulation?

I am in the process of completing my energy efficient house design. Approximately 80% of the Building Envelope will be a Double Stud Wall Construction allowing for roughly 11" of Cellulose Insulation in addition to a 1" Rigid Insulation outboard of the Sheathing and inboard of the Hardie Cement Fiberboard Skin. The Remaining 20% of the Envelope will be Double Glazed Fiberglas Windows with emphasis placed on the South Elevation (Perhaps 60% on South, and 20% each on East and West). However, on the South Elevation I also have two sections of Trombe Wall - each 8' in width and 12' in height.

Asked By Thomas Tricarico | Mar 1 15
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