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0 Answers

air to water heating - flat plate with water storage or long copper pipe in water storage

in an effort to make our house more comfortable, and to eliminate the drift of air we currently are in the opportune to raise the living room floor with a sub-floor and by doing so, include in-floor radiant heat.

plan is to:

raise living room floor (440 SF) by about 14 inches, with standard plywood and 2x12 timber.

on top, install R10 EPS insulation with 5/8 PEX/O2 barrier 6 inches on center, encased in 2.5 inches of sand/cement and 15 mm laminate flooring

Asked By kevin Kersten | Oct 22 16
0 Answers

DHW Power Demand No Longer and Issue?

Traditionally, heating and cooling requirements have been the largest energy draw in homes. The ability to relegate heating and cooling to 2nd or even 3rd place in a home energy draw hierarchy is now possible with better building techniques, such as PH. It has been generally agreed that the new king of the draw is DHW. However, I wonder if that is still the case now that HPHW systems have hit the market. I live in a heating dominated climate. The maximum heating demand allowed per PHI is 4.75 KBtu/SF or 5.2 KBtu/SF per PHIUS+ for my climate zone.

Asked By Jonathan Lawrence CZ 4A New Jersey | Oct 22 16
3 Answers

Sun Bandit solar water heater

Hello. I was reading the article by Martin Holladay entitled "Solar Thermal is Really, Really Dead" and enjoyed the discussions going back and forth on the topic of solar water heating methods. I am planning on building a small 600sq' SIP cabin in the area of Nelson BC (climate zone 6) next year and I found this product listed as being one of the most efficient for heating domestic hot water on the Canada Energy Guide site. It says it can also be used for space heating via a radiant floor system or perhaps radiators.


Asked By Scott Wilson | Oct 21 16
6 Answers

Double walls, dense packing, and bendy sheathing

Many articles on double stud walls suggest fiberboard or gypsum as the exterior sheathing to prevent winter moisture issues. Given that thick walls require higher cellulose density, what tricks are there to keep the sheathing from bulging?


Zone 5, Rochester NY

Asked By John Ranson | Apr 25 16
0 Answers

Zone 3 roof dampening concern unvented attic

New home construction - roof design
asphalt shingle, 30# felt, OSB, 5 1/2" open cell foam. Should I be concerned about the design causing moisture problems over time?


Asked By Mike Beckham | Oct 22 16
1 Answer

How much insulation for a steel beam?

How much insulation do I need over a steel beam to stay above the dew point inside the house?

This is new construction in progress, in NC. The I beam is over a door and window assembly and contained within the wall, sandwiched between the sheathing and drywall. However, no consideration was given to insulating it in the design.

Asked By Jeremy Turner | Oct 22 16
6 Answers

Garage and root cellar insulation

I received a call from my mechanical engineer today asking me how I planned to insulate the garage and root cellar ceilings. Both rooms are in the basement and above those ceilings are first floor living spaces. I told him my plan is to dense pack them with cellulose and probably add an inch of Polyiso covered with a layer of gypsum to break the thermal bridge and satisfy fire code. I was planning on insulating the rim joists with a couple of inches of ccSF on the inside, the only area in the house with the nasty stuff, mineral wool on the outside, and then dense pack would fill the bays.

Asked By Jonathan Lawrence CZ 4A New Jersey | Oct 19 16
7 Answers

Double backdraft damper needed for bathroom fan?

I am going to install Panasonic exhaust fans in our bathrooms in new construction through an unvented attic.. The Panasonic fan comes with a built-in damper and their installation guides mention using a wall cap with a damper too. This means there are two dampers.

The Panasonic damper is very light plastic does not seal well and opens easily. The wall cap damper is typically metal, making it a little harder to open. Our HVAC contractor suggests not using a damper at the wall cap but this worries me.

Is the best approach to use two dampers in line?

Thanks for your advice.

Asked By Jeremy Turner | Oct 19 16
60 Answers

While I love radiators, I hate using fossil fuels

I live in an 1890 Victorian in Southern Pennsylvania, heated by oil. While I love radiators, I hate using fossil fuels! Is there a way to use green technology to use less oil? My methods to date have been uncomfortable - installing a wood stove.

Is there a way of boosting the boiler with green energy? Would geothermal help? I'm newly divorced and ignorant about systems!
Thanks, Susan

Asked By Susan Hanway | Aug 28 16
16 Answers

Best building envelope approach for an owner-built home in northern Wisconsin?

Setting the Stage:

My wife and I purchased a vacant farm (no buildings) with a south-slope in far Northern Wisconsin and have been planning our next home for a few months. We would like to build a "pretty good house" that finds that happy place between great energy efficiency and economy. This would be an owner-built home on a basement foundation. Our forest has plenty of millable pine and oak that we intend to use as much as possible for the build (framing, siding, flooring, etc.).

Asked By Michael Sterner | Oct 17 16
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