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12 Answers

Understanding vapor transmission and perms

I understand the different levels of vapor retarders and how a lower perm rating means less vapor comes through the material. What I don't understand is how this affects the amount of water vapor coming through in real life.

Asked By Nick Welch | Oct 6 14
1 Answer

We have a diesel burner for water heating that heats pipes and radiators

We have a diesel burner for water heating that heats pipes and radiators to keep the home warm in winter. Is there solution instead of that burner using free solar heating?

What is equipment do we need ?

Asked By khalid aldaher | Oct 10 14
3 Answers

What sheathing under a metal roof?

We are building a garage. The roof is a 12/12 pitch. We would like to put spray foam insulation under the roof when we have the funds. We have a thermos roof on our house and love it. We thought we were going to use 3/4 inch T&G OSB for sheathing. We then heard complaints about screws stripping out. We really don't want purlins because we live in an area that can have a lot of hail damage. Should we switch to the more expensive plywood? I feel like we are going around in circles.......

Asked By Jane Metzger | Oct 9 14
1 Answer

How to reduce AC noise through a bedroom window?

hello….I live in a groundfloor apt. there are two a/c units right outside my bedroom window, about 2 feet away...my unit and my upstairs neighbors' unit. i don't use mine much, but they use theirs ALL THE TIME, even when it's 65 outside! i really don't want to move, but i cannot go through another summer of listening to the pervasive deep buzzing sound of their unit. so far, i have tried styrofoam insulation and also sound board, cut to fit into the window on the inside which has a 3 inch sill all around it. have also hung a heavy thick blanket.

Asked By Cynthia Oeser | Oct 10 14
9 Answers

Building science options

looking for advice on options on getting into building science & green renovation ---- it seems there is still a disconnect between the building science research and the builders in the field.

Quick background on me --- I have a Chemistry degree and taught the subject for 8 years before leaving the field to be a remodeling contractor --- so I am very interested in the science behind renovating from an energy standpoint.

Asked By Jason Schatz | Oct 5 14
9 Answers

Post-cure/long term off-gassing with Bayer’s Bayseal closed cell spray foam insulation (“SFI”)

I am considering having Bayer’s Bayseal closed cell spray foam insulation (“SFI”) installed in the attic and basement rim joist at my New Jersey home. I am interested in hearing thoughts on the recent concerns over off-gassing of the SFI that I have been reading about. My questions assume SFI installation gets done correctly (I have read about the improper installation problems causing odors). Anyway, the issue of concern/interest for me is long-term off-gassing AFTER a properly done SFI job.

Asked By D S | May 14 14
4 Answers

Adding outside air vent to existing HVAC?

Hi all,

I live in Los Angeles and dislike AC. We have AC on the second floor of our home, but in the evening when the outside air is down to a lovely 68-70 degrees, our inside air is still 85. My wife wants to put on the AC. I want to bring in outside air. But simply opening the windows doesn't really work well. What I really want is to integrate an outside air vent into our HVAC system, thus pulling out the inside air and replacing it with outside air. Trouble is, I don't know even what this would be called, so I can't seem to find any information on it by googling.

Asked By Franz Metcalf | Oct 8 14
5 Answers

Retrofitting new wall inside existing frame

I have an interesting challenge in my 1941 1500SQFT energy retrofit in Minneapolis (Zone 6-7). I want to maximize realistic R-value while preserving the existing siding and sheathing, which we can assume has no vapor barrier (this will be verified when we open it up). While I would normally prefer to wrap the exterior, this is not possible at this time. There is no historic value to the plaster/sheetrock, and we're demoing kitchen and bath anyway, so I intend to do all insulation from the inside. The home is all 2x4 16"OC construction with old yellow fiberglass batts.

Asked By Ryan Griffin | Oct 8 14
7 Answers

US triple pane with uncoated glass?

I've been thinking that for the shaded south side of my Minneapolis home, triple panes with no Low-E coating might be best. I'm looking for a US made window that's decently insulated with high SHGC. I've asked a few manufacturers if they would make me a triple pane with clear glass, but I haven't found anyone willing to do this. Would I be giving up too much insulating performance (or interior heat reflectivity) with clear glass, and is the a US maker who will do this?

Thanks,
Ryan

Asked By Ryan Griffin | Oct 5 14
3 Answers

Surface 4 low-e... condensation issues?

Hi,
Your articles from April 2013, reference the issue of higher condensation on surface 4 using low-e products like i81.
Is there an update on this surface 4 condensation issue with the new i89 material.
Thanks,
Pholz

Asked By paul holzsc | Oct 8 14
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