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9 Answers

Seasonal humidity and lack of outside airflow

Hello,

Asked By Geoff York | Mar 2 15
1 Answer

Will adding rigid foam insulation to the inside and outside of my d-log house cause mold?

I am planning to add rigid foam insulation to the outside of my old leaky d-log house and adding douglas fir slab siding with chink. My electrician would like for us to fir out the inside to avoid having to router out chases for new wiring. If I add foam insulation (open or cloased cell) to the inside will I risk mold on the logs? The house is located in the upper Arkansas valley in central Colorado, zone 6 I believe.

Asked By Judith Blythe | Mar 3 15
4 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
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
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
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