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2 Answers

My basement is fairly dry and well above the local water table
and hasn't had any water ingress over any of the major storm
events we've had, and has never had a sump pump. So I don't
really care about storm water; what worries me is the potential
for internal plumbing leaks as there's no way for the basement
to drain until it basically fills all the way up. So I'm
thinking of putting in a sump pump but into a small well that
*doesn't* connect to whatever gravel/earth/whatever is underneath
the slab -- it would be connected to the slab and sealed in and

Asked By Hobbit _ | May 16 13
9 Answers

I've been re-reading Martin Holladay's posts on water heating as I once again deal with a small-ish super-efficient house: 1900 ft2 with a heating load of less than 20 kBtu/hour. The homeowners have access to propane and electricity and here in MN, electricity is still generated by a lot of coal, although the homeowners are planning for a pv system.

At the moment I've narrowed heat/hot water system ideas down to three:
1. use a 6kW modulating electric boiler for space heat (hydronic radiant) and also to fire to an indirect tank for hot water. Also, use a drainwater heat recovery device.

Asked By Rachel Wagner | May 14 13
3 Answers

I was told that my central AC needs a larger return duct. The symptom was that the low pressure line at the compressor was icing up on the outside. Does this make sense? I had thought that if the system was low on freon that this was a symptom.

I am handy but need some input into the size requirements of a return duct versus the output ducts. I would assume them to be about the same size.

Asked By john friede | May 13 13
2 Answers

Everything was going well in our green home planning process until a short conference call with our mechanical contractor today.

His assertions:

1. our home will be too dry (we are omitting a humidifier)
2. our bathrooms still need exhaust fans (we are installing an HRV) in order to pass inspection and meet code
3. an HRV should never pull exhaust air from the laundry room as it will create negative pressure

Asked By Troy Stevenson | May 10 13
5 Answers

Background: new home to be built in Zone 4A. Living area about 2200 sq.ft. on main level. On lower level is a 778 sq.ft. shop space, and 450 sq.ft. for future use. My energy rater estimates the cooling load at 18,000 BTUs for everything.

I’m thinking mini-splits. Mitsubishi offers several outdoor heat pump units that can have 2, 3, or even 4 zones, matched with any mix of the interior units (with an appropriate combined total of course). I’d like at least three zones to meet both distribution and the diverse needs of the spaces, but there’s a big question.

Asked By David McNeely | May 7 13
3 Answers

I am having trouble finding the best possible configuration for a mini-split system. I'm building a small house in NW Ohio, a story-and-a-half with full basement). Total calculated heat load is 16,000 Btu/hr.

Asked By Andy Chappell-Dick | May 9 13
8 Answers

Plans / pics are attached

Exterior walls are SIPs R-24 with 1-1/2" EPS stucco
Center 'bumpout" is typical 6-9 stick with 3" EPS (interior to be sprayed)

WIndows are Integrity Low E3

window wall south facing

Proper way to heat and cool

We are in the process of building a very open floor plan home with catheral ceilings in CT (zone 5) with 2 levels.

Main level - 9-17' ceilling heights
Lower Level ( Walkout) has radiant in an exposed slab and footings over 2"EPS.

Asked By Chris van Wilgen | Feb 5 13
5 Answers

I have just installed both range and bath vent fans and 4 passive air inlets. We live in big orchard and farm country where the flying and crawling insect populations are often swarming. When they hatch they can reach infestation levels.

None of the fan and make up air products have adequate protection and none have exterior (intake side) filters. The Panasonic and Aldes products are particularly weak in this area.

Asked By Oak Orchard | Apr 30 13
9 Answers

Does anyone have any experience with or thoughts on the hybrid "dual fuel" natural gas furnace systems that are combined with an air-sourced heat pump (instead of an AC only unit)?

The intent is for the heat pump to provide heat when its most efficient, but then switch to gas when the outside temperature drops to the point where the heat pump is no longer efficient or effective.

Asked By Jonathan Rich | Apr 21 13
1 Answer

Hi I have a raised ranch.
I am gutting the first floor and adding a 2nd story addition. With full attic.
I am going to use open cell spray foam.
All walls and attic roof lines. After the addition I will use it to finish the basement.
I am running a 90+ efficient furnace for the 1st floor and basement.
Which does draw fresh air into it
I am planning to get a similar unit for the addition
3 baths with fans, 1 600 CFM range hood
Would I need to install a HVR unit?
I live in the Midwest. I heard stories about windows icing up and having to open windows.

Asked By Brian Pasold | Apr 23 13
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