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2 Answers

Unvented cathedral ceiling — insulating from above

I am re-doing my family room roof, which is a cathedral ceiling.

Since the roof is being re-shingled, I thought it a good time to remove the sheathing and lay down some closed cell foam. I have some unopened from a previous project

Everything I've read about unvented Cathedral ceilings talk about them drying from the inside. Obviously this can't happen if I'm spray in the closed cell foam onto the dry wall ceiling from above

The ceiling is 8" from drywall to plywood

Asked By Paul Buchkowski | Jun 25 16
3 Answers

Insulation/ conductivity math help, please

I recently read one of Martin's posts about (so-called) radiant floor heating.
It was exactly what I needed. The dream of a toasty-warm floor under bare feet is only a dream- unless the boiler runs all the time- either to keep up with a poorly insulated and/or drafty house- or if a well-insulated, tight house is overheated.
Instead, I'll opt for mini-splits.

Asked By Ben Rush | Jun 25 16
9 Answers

Room on second floor of house that cannot be cooled with AC.

We have a 40 year old house with a 7 year old central air unit. The duct work makes it difficult for the AC to keep the upstairs as cool as desired on extremely warm days (92+). We have dual zone thermostats so we just use the upstairs unit for AC, which helps. We recently replaced the windows and have insulated the attic, so overall the system is adequate. We do, however, have one room that consistently runs 8-10 degrees warmer than the rest of the second floor. Cool air is coming through the register.

Asked By Tim Duffy | Jun 25 16
6 Answers

I'm chemically sensitive and the neighbor uses lots of pesticides that make me ill

Hello. I own a small 2 story semi-detached home, 1024 sq ft in all. I'm chemically sensitive and the neighbor uses lots of pesticides that make me ill. I would like to keep these VOCs out. Air purifiers have not worked for me.

Asked By Brenda Koehlert | Jun 24 16
21 Answers

Direct vent vs power vent gas water heaters

A recent blower door test/audit has alerted me to the fact that my natural draft hot water heater can backdraft in worse case scenarios (range hood/clothes dryer/bath fan on). It seems to reverse back to a correct draft after a few minutes. It's only about 6 yrs old, so I hate to replace it, but not as much as I hate the idea of the back draft.

Asked By Erik Addy | Mar 8 16
2 Answers

Upgrading a crappy HVAC setup

My wife and I are in the process of purchasing a new home in Northern NJ. The home was built in 1986 with forced hot air heat and withOUT air conditioning. Air conditioning was added later.

As a result, the house has two sets of ducts. One set feeds heat to both floors from the basement. The other feeds conditioned air to both floors from the attic - but there are too few ducts on the first floor for the A/C to work well for that floor.

The furnace uses oil and is likely nearing the end of its life. Also, the house has a pellet stove.

Asked By Matt Culik | Jun 24 16
3 Answers

Atlas ThermalStar X-Grade Reviews?

Does anyone have experience using Atlas's ThermalStar Product -- X-Grade?

I am looking for an alternative to XPS in a below grade product. It will be used beneath the thickened edge (essentially a footer) of a monolithic slab on grade. The 25 psi version of this product seems like it could be a winner for me but I wonder if others have tried it out? What is your opinion of it?

I recently spoke with Bob Murphy of Universal Forest Products about this EPS foam board and it sounds like it has a lot of promise.

Asked By michael Iacona | Jun 24 16
11 Answers

Heat pump water heater + AC + refrigerator combo, someone?

Only wishful thinking ,

has any commercial products come up with a combo of any of the floowing items ??

- heat pump water heater ( tanked )
- heat pump AC
- heat pump heat
- refridgerator/freezer ??

I don't know why, but i think i recall looking at a product a few years ago that
comboed AC and water heater ??? can't find it anymore

what about water heater and refridgerator ?

I'd say, if use the heat generated by refridgerator/freezer pump,
would it make enough to hold up water temp in a tanked WH ??

Asked By Jin Kazama | Jan 7 13
13 Answers

Geothermal vs. air-source heat pump

I have researching and getting quotes on hvac for a while now.. It is getting to crunch time.
Well insulated, tight house.

All three quotes include:
3 units, 3 air handlers, each zoned 3 times. Rigid Trunks and short flex runs.

option A. Carrier 18seer 25vna08... 5 stage. ( I don't like the potential harmonics problems of their greenspeed)

option B. Lennox x25 top of their line variable.

option c. Waterfurnace 7 series geothermal units. horizontally drilled ground loop.

Asked By Dean Sandbo | Jun 22 16
8 Answers

I am thinking of an unvented cathedral ceiling

Hi. I am thinking of an unvented cathedral ceiling. Living in Hazelton, BC (Zone 4A, I believe), and would like advice on my proposed insulation plan. Staring from the underside: vapour-retarding paint; sealed gypsum board; 3/4" strapping; 2" or 3" Roxul board.

I would like to achieve at least an R50.

Asked By Mike Tomlinson | Jun 24 16
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