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9 Answers

Does radiant heat recycle water

With regular radiant heating systems that use warm/hot water to run through tubes in the floor to heat the home, what happens to this water - does it get recycled through the system, heated up again, or does it go down a drain?

Asked By Celina Jones | Nov 22 14
2 Answers

Can rigid foam insulation have an air space between it and rim joist?

I am insulating my rim joists with 2" rigid foam board. Most of the rim joist is bare, and the foam fits along it nicely. Some sill boxes have some small irregularities (vent pipes, plumbing, etc) that I have worked around easily enough.

Asked By Susie Derkins | Nov 22 14
0 Answers

Round window flashing and water management

I have a situation with a remodel on a 1970's house with one round window that was replaced. The new window is installed, and the company had me replace siding and trim around the window. The window is an aluminum clad round (well, round with a flat section at the bottom, roughly 4" above where the siding stops).

We started out by installing sheathing on the wall- it had been built with no sheathing- it's a complicated wall with two round windows, and there are custom steel brackets holding everything in place (sort of).

Asked By lavrans mathiesen | Nov 23 14
7 Answers

Home energy monitoring programs

I am building a net zero energy home to Passive House standards in the Seattle area. In addition to having it be as efficient as possible, my goals were to use renewable materials (no foam), eliminate thermal bridging. have a protected air-barrier and to keep the OSB warm. I'm using dense packed cellulose in the R-50 walls and R-85 roof (cathedral ceiling with parallel chord trusses). The wall assembly is a double stud system with an inner 2x6 load bearing wall and an outer 2x4 wall.

Asked By Gerald Blycker | Nov 21 14
0 Answers

What's a good damper for a bath fan/range hood vent?

My bath fan vent is basically a big hole in the house to the exterior and sucks air out of the house in the high New Mexico winds, which today reached 30 mph. There's no damper or air check valve or anything like that installed up there, and I'd like to rectify it. What do people use for this situation? A standard butterfly damper? Something louvered? This thing? http://www.batticdoor.com/bathfandraftblocker.html

Asked By Nathaniel G | Nov 23 14
6 Answers

Proper wall to attach rigid foam to the inside of the wall?

Question: what is the best way to attach rigid foam (foil faced polyiso) board to the inside of a finished wall? Can I just use longer drywall screws to go through the 1" foam and existing drywall? What if I'm going with more than that (say 2 or 3 inches of polyiso)? I'm worried that this method would have a greater tendency to pop the drywall screws out under small impacts like hanging a picture. I'm also worried that the walls will sound hollow or be bouncy when knocking on them. What are the best practices for each thickness of foam?

Asked By Ryan Griffin | Nov 17 14
12 Answers

Insulating an uninsulated Cape-style home (cathedral/knee)

Hi all, new member here; new homeowner too.

Asked By Nathan Schulte | Nov 20 14
0 Answers

Choosing Insulation for a Cathedral Ceiling

This is my situation: I am located in colorado, where is is generally dry, gets hot in the summer and cold in the winter. I am in process of building my own house and want to make choices that wont come back to bite me down the road. With that in mind I want to avoid any moisture issues inside my ceiling cavities. What I have so far is a stick framed cathedral ceiling using 2x12 dimensional lumber. On top of the rafters I installed 1/2" CDX sheathing and covered that with grace tri-flex (I wish I had used felt paper).

Asked By Patrick Decker | Nov 23 14
11 Answers

Plumbing vents exiting ridge cap

Can't seem to find anything in the code, easily missed though. I have a customer who wants a metal roof installed however they have had bad experiences with pipe flashings through the roof and don't like the look of them. While I don't care for the pipe boots, (for metal roofing), appearance they seem to work well.

Anyway, to the question... Is there anything code or common sense wise that says vents couldn't go through the ridge cap? I know it wouldn't look as good but, would limit water flowing over them.

Asked By RMills Miller | Nov 21 14
5 Answers

Mod-con forced hot water system that squeals

My plumber recently replaced the boiler in my small 3-zone Colonial with a Lochinvar WHN-85 boiler with a Lochinvar SIT 40 indirect water heater. Seems to work well, but I've been having trouble with noise.

First, the boiler occasionally emitted what I called a foghorn noise out of the exhaust pipe (the plumber opined it was a French horn). The solution was to tune the mixture to the rich side of the specified range (i.e. more gas per air, and more CO2 in the exhaust), which made it go away.

Asked By Daniel Griscom | Nov 19 14
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