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29 Answers

Rheem's condensing water heaters (storage)


My 14-year-old electric water heater is starting to look a little long in the tooth. Time to upgrade.

So, I'm looking for intel on Rheem's Professional Prestige Series: High Efficiency Condensing Power Direct Vent (RHE50) or its sister sold by Home Depot - Rheem EcoSense High Efficiency Power Direct Vent (ECORHE50).

I can't find any online reviews of either product (save one favorable review on HD's site).

For several reasons, I'm looking at a high efficiency storage water heater instead of tankless.

In Green products and materials | Asked By Michael Brahmey | Oct 11 14
12 Answers

Makeup air in all electric home?

I have read a lot of blogs and questions that, quite reasonably, recommend makeup air for kitchen exhaust fans in tight homes. The use of these fans can cause backdrafting in combustion appliances. But what if the home does not have any combustion appliances? We typically design very tight homes, around 1 ACH(50) with no combustion appliances. We use heat pump water heaters, Mitsubishi mini splits, and electric condensing dryers. We also use Induction ranges and cooktops. No fireplace. We tell our clients that if they want a fireplace, they can have one...outside.

In Mechanicals | Asked By Rob Shearer | Feb 11 15
10 Answers

White, powdery floor insulation--can you ID this?

Picked up this image form another forum, and it might be a stumper. Who has the answer?


In General questions | Asked By David Meiland | Feb 15 15
10 Answers

Gable vents vs. wind-driven snow: Is there a brand of gable vent known for preventing fine wind-driven snow intrusion?

Another fine snow/strong wind event here in eastern Canada today. After pretty much every storm like this I tend to find piles of snow in clients' attics, right around the gable end vents on the windward side of the attic (naturally). In one particular case it seemed to be a pretty big factor in the amount of moisture in the attic, as there was serious frost covering most of the roof deck. These gable vents always seem to have the louvers and screens that are meant to prevent rain and snow intrusion, but they fail in this regard when faced with very fine snow being blown sideways.

In Green products and materials | Asked By Peter Rogers | Feb 15 15
9 Answers

Should builder charge separate overhead & profit when using a cost plus % contract

I'm in the process of hiring a builder and three of them agreed to provide a "cost plus percent" quote.
They all independently came up with the same percentage, so it wasn't a figure I was forcing on them.

In Project management | Asked By Adam Peterson | Feb 15 15
14 Answers

In search of an airtight ceiling, I have heard talk of sheetrocking the ceiling & dropping in a 'second' ceiling

In search of an airtight ceiling, I have heard talk of sheetrocking the ceiling and then dropping a 'second' ceiling where lighting and maybe HRV ductwork etc. could be installed. I am wondering how this was accomplished.

For my home I plan to build, a nine foot ceiling in a one story home with trusses, plastic barrier and then sheetrock attached to the trusses. Are 2 x 4's hung down about six inches with some kind of joist hangers, and another layer of sheetrock installed with lighting and HRS ductwork in between?

In Green building techniques | Asked By Steve Vigoren | Feb 13 15
6 Answers

How do I construct a brow roof on the first story of a two-story structure?

See attached file photo. I can find all sort of plans for different brow roofs with the exception of the one in the attached photo. That photo is titled the Stanton House with overhang and credited to Martin Holladay,

In GBA Pro help | Asked By Steve Skalski | Feb 14 15
1 Answer

How come some questions are answered by D Dorsett and others by Dana Dorsett?

Are they the same person?

In General questions | Asked By Alan B | Feb 15 15
1 Answer

Foaming EPS slabs on roof

Planning on a timber frame with 2 layers of 5" eps, staggered joints over cathedral ceiling. This will have 2/4 sleepers on top of eps running up roof for a vented roof. I am concerned about using canned foam between joints as I have been reading about shrinkage, settlement of frame, etc. causing foam joint to crack. Any thoughts or experience using something like foam sill seal between joints? Roll it out along edge of slab, slam next slab against it. Should be flexible enough to move with the house. Any suggestions on a better product to use?

In General questions | Asked By John H. Stehman | Feb 14 15
2 Answers

Can I replace open-combustion HVAC in my attic with a sealed-combustion unit?

Bought a house in NH a few years back and it has gas furnace in attic and i am tired of heat loss, constant running, and melting snow! After I limp the house thru the rest of this winter i am going to explore spray foam insulation (prob close cell so i don't have to deal with vapor barrier etc) and i cant with current furnace. The furnace is 20 yrs old and seems to fire/cycle all night long. The ducts and everything is also in attic. Can i replace this open combustion (or un sealed or whatever the term is) furnace with a sealed unit? Does the returns and ductwork have to be changed too?

In General questions | Asked By Andy Giaconia | Feb 14 15
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