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5 Answers

Seasonal humidity and lack of outside airflow

Hello,

Asked By Geoff York | Mar 2 15
4 Answers

Double wall exterior sheathing

I am designing a near zero energy home in climate zone 5 and working out the details for a double wall system.

There is a lot of talk about what kind of sheathing to use or not use due to the fact that the sheathing will be very cold. As I understand what I have read so far, it is recommended NOT to use OSB or foam but OK to use DensShield Gold, structural fiber board or plywood in Zone 5.

Asked By Terry Herschberger | Mar 2 15
5 Answers

Why is it so trendy to hate on radiant in-floor heat?

I recently built a 2000 square foot house in climate zone 7. The building is two stories on a slab heated by a Navien 240a combination boiler. There is no heat source on the second story, and the simple system has only one zone, which is all it needs because all the rooms in the house stay at the same temperature--maybe it's a few degrees cooler in the upstairs bedrooms if the doors are shut for 24 hours or more. I spent just over five grand on the heating system--installed--although I got a tankless water heater in the process, so the real cost was more like $3500. How is that overkill?

Asked By Josh Jipson | Mar 1 15
6 Answers

Running PEX in-floor in addition to baseboard

I'm building a new wood frame home with hot water baseboard heating in climate zone 6. The bathroom will have tile floors and I was thinking of using some electric resistance heat under the tile along with a baseboard hot water radiator in the bathroom. These electric systems are not inexpensive to install or operate so I am now considering simply running loops of Pex (the supply line to the bathroom radiator) between the joists to keep the tiles warm before the water in the line gets to the baseboard radiator.

Asked By George LaLonde | Mar 2 15
3 Answers

Basement finish floor, slab on grade

With the help of this site I insulated and framed my basement (90 year old house, 8-9" concrete walls). I did 2 inches of XPS (EPS in hindsight would have been greener but I had a deal on some XPS), 2x framing with Roxul R-15 in between 2x. Rock is next and then floors.

Asked By Sean Cotter | Mar 1 15
1 Answer

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
7 Answers

Buying a house and want to make it super efficient. I have some concerns about the attic. Can you help?

I am about to close on a house that was built in 1972. It is in Longview, Texas. It is 2100 sq. ft. The garage was made into living space at an unknown date. Has a 3.5 ton central air unit and electric furnace for heat (inspector said that is too small and likely was in place before the garage was converted). Flex type ducting in the attic. My goal is to eventually do the entire place from top to bottom, as I can afford it, and make it cheap to heat and cool. I have several plans in mind. Insulation of the attic I think will be my first step.

Asked By Sam Vail | Feb 26 15
5 Answers

What is the correct climate zone?

Can anyone point to a web site that will be zip code specific to determine which climate zone you are located? The Department of Energy web site leaves something to be desired. I cannot determine a clear explanation of climate zone 4 and 4 Marine. It seems there should be a site to enter zip code or address and get definitive information regarding climate zone.
Thanks,
William

Asked By william dempsey | Mar 1 15
7 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
5 Answers

What is a correct way of fastening two layers of 2" rigid insulation to the exterior of a 2x6 wall?

I would like to know the correct way to fasten two layers of rigid foam insulation where the total thickness is 4". I am concerned that when hanging this thickness of foam it will be difficult to be sure that the siding application is secure. We will be using HardiePlank horizontal lap siding. This is a form of cement board and heavy on it's own. Any advice.
Thanks

Asked By william dempsey | Feb 26 15
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