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0 Answers

Air space required for ge geospring hybrid electric heat pump water heater?

I'm interested in going to a heat pump water heater and looking at the GEH50DFEJSR geospring model. I see in the manual it says it needs a 10×10x7 room or louvre door or duct kit. I'm curious if a vented pass thru to a larger room works the same? Kinda like a cold air return. The room is 8x5.5x8 and would rather not put a louvre door up. Any recommendations? Anything else I should know before purchase?

Thanks so much!

Asked By Stephen Audretch | Jul 24 16
4 Answers

Looking for design software recommendations

Hi -

I'm a new member and I'm looking for recommendations for relatively easy-to-use design software (I did try searching the site but didn't find anything discussing that). My first task will be a simple floor plan so I can ask the good folks here for advice on placing mini-splits. Further down the road, I'd like to be able to draw out details for roof and wall assemblies for the retrofits I hope to do. Any then maybe a tiny house (or at least a tiny shed) in the future.

Asked By Nickolas Van Kleeck | Jul 23 16
14 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
1 Answer

Preferred underlayment under metal on unvented roof?

Hi Everyone,
Need to make a final decision on which underlayment to use under a metal roof on an unvented roof system. The roof is currently built as follows: Beams on 5' centers; 1 1/2' T&G decking; 3/8" plywood diaphragm - seams taped; with TriBuilt granulated self adhering underlayment on top of the plywood.

Next I'll be screwing down 5 1/2"RayCore SIPS panels over heated space and framing boxes over the eaves covering everything with 5/8" CDX. Still looking at metal roof products but am zeroing in on a high seam (1 3/4") snap lock system. Roof pitch is 2/12.

Asked By Robert McKee | Jul 23 16
8 Answers

We are building a 700-sq.-ft. cottage on southern Vancouver Island, Zone 4 Marine

The plan is to use 4 inches polyisocyanurate - R22.6 - (glass fiber covering) exterior insulation no sheathing except for earthquake walls. No insulation in the 2x4 wall cavities, tyvek on the exterior of the foam and vapor barrier between the polyiso and the framing. ls this ok or will we have problems. We have to present our wall assembly plans to the city and the city wants a vapor barrier but we are not sure if this is necessary.
Sandra Garraway

Asked By Sandra Garraway | Jul 22 16
1 Answer

Abandoned brick chimney - is it hurting energy efficiency?

Brick single-story house, brick chimney protrudes from the exterior wall from ground level, basement.

Furnace & water heater used to exhaust - clay liner.

Water heater was then orphaned, smaller metal liner inside the clay liner.

Water heater was then removed. Metal liner capped from the bottom.

At this point the chimney is unused. It's still open from the top, has a cap, but has a couple "tin-can" caps at the bottom where the furnace & water heater flues would connect.

Asked By j pritzen | Jul 23 16
6 Answers

Exterior walls to meet code without gypsum?

Hello,

Maybe this has been discussed here. Feel free to link me to other threads that I haven't seen if this is fully covered elsewhere.

I'm not a fan of drywall. A quick rundown with no real surprises: it used to be cheaper; now it's not. It also takes plenty of work and more money to make it look nice. It's heavy but also very breakable. Even when you don't break it, it's messy. Etc, etc. I *am* a fan of 3/4 plywood, which is less breakable, more durable, and looks nice.

Asked By Minneapolis Disaster, 6B | Jul 22 16
51 Answers

Questioning my logic...GSHP, ASHP, radiant?

I'm in the planning/almost ready to break ground stage of a new home and I'm beginning to question my sanity when it comes to figuring out the right approach for heating & cooling.

The home is:
North end of Climate Zone 5
Main Floor: 1700 sq ft + 1000 sq ft garage, vaulted ceilings through much of it
2nd Floor: 1100 sq ft (2 bedrooms, 2 baths, living room) primarily over the garage
Basement: 1700 sq ft, partial walkout + 1000 sq ft shop under the garage (separated from the rest of the basement)

Walls: R30+ (2x6, 2" XPS outside, 2lb SPF for sealing + 1/2lb SPF for cavity fill)

Asked By Dave De C | Jul 16 16
8 Answers

Will positive pressure work to vent an attic (i.e., blowing air in)? Attics exhaust fans are a bad idea. But what about blowing air in (using positive pressure).

My father is interested in removing heat from his attic to try to keep the upstairs of his house somewhat cooler. I have advised him that generally speaking, attic fans are a bad idea, which he has come to terms with. However, with that understanding that creating negative pressure in the attic can cause all kinds of problems (sucking out air from the conditioned space, possible back-drafting of combustion appliances, etc.), he has come up with the idea to blow air into the attic instead (i.e., creating positive pressure) to force the hot air out.

Asked By Erica Downs | Aug 12 12
1 Answer

Ads on GBA prime

Over the last week I've noticed the appearance of advertisement on GBA prime. Is this due to a technical problem or is it the result of a change in vision?

My decision to join GBA prime was motivated by the fact that it would be free of ads. I'm sorry to say that if this is the direction that Taunton Press wishes to follow, that once my membership runs its course that I will regrettably not be renewing.

Asked By Marc Labrie | Jul 23 16
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