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9 Answers

Losses Through Gas Fireplace Vent/Duct?

Climate Zone 6A, Ottawa ON, building a highly insulated house.

Does anyone know what kind of losses you can expect from the envelope penetration for a gas fireplace?

Asked By Lance Peters | Aug 2 17
12 Answers

Retrofit of a cathedral ceiling

I am living in a Log Home in Madison WI. (Zone 5-6) with a vaulted Ceiling. (2x6 rafters R-19) I am hoping to redo the roof soon. I wanted to put on a layer or two of Rigid Foam. XPS or EPS. Ideally getting close to R-20 plus the 2x6 insulated cavity. I will then put a standing metal seam roof on top of the foam using furring strips.

My issues are this. I am concerned that I will be trapping moisture between the XPS or EPS and the Vapor retarder or Vapor Barrier that is most likely installed on the warm side of the house. Right behind the sheetrock and before the batt insulation.

Asked By User-6884681 | Jul 25 17
1 Answer

Wi-fi app to control minisplit systems


there have been a few different ways of achieving wifi / app / remote control of mini split systems, most all proprietary and quite expensive.

I came across one I haven't seen / thought of.and couldnt find here on a search

instead of directly controlling the mini-split via wifi, this method is to directly control a third party IR transmitter, in line of sight of the mini split, by wifi/app.

the IR transmitter then communicates with the IR mini split receiver

So the app will then duplicate all the remote control's buttons.

Asked By P Ha | Aug 10 17
11 Answers

Triple-pane windows for a high-efficiency cabin

1400sq. Ft. cabin...Zone 7 10,000 HDD with R40 walls and R80 in roof. Looking for ideas for windows. I'm probably looking at a manufacturer in North America for costs and timeline to get.
Have looked at H-Windows, in person and several others online, including Marvin "Tripane".

Any pluses or minuses with any of them would be helpful.


Asked By Steve Lenertz | May 29 17
2 Answers

Want to install minisplit — need advice

Hi everyone!

Our master suite has only 1 small ac vent, none in the closet or bathroom, this makes it very uncomfortable in the summer in Florida. We have a large slider window and a really small double hung window in the bathroom. This makes windows units not a good choice as I've tried to install many without success.

We have a flat roof over this part of the house so we can't run more ac to the other rooms.

3 walls are outside walls, one wall is concrete the others are basic construction, minimal insulation and no insulation on the roof. Both windows are double pane.

Asked By jgraeff | Jul 22 17
1 Answer

Installing wall exhaust fans at a downwards pitch?


I am installing a wall bathroom exhaust fan (Panasonic WhisperWall 70) directly in my external wall. I know that many people angle their ducts/pipes at a slight downwards pitch towards the exterior. There will not be any ducts, just the wall sleeve.

I was thinking of installing this bathroom fan at a slight pitch (even through installation instructions do not say to do so). Is there anything wrong with me doing this?

Asked By Rocky12 | Aug 9 17
7 Answers

Vapor drive and porcelain tile exterior walls

The nice thing about building a house on one's own is that the building gives you feedback before the finishing touches lock things in. One such lesson for me is summertime vapor drive. I have had Durock CBUs installed over vertical 1x3 furring for some time now with plans to install veneer stone later. The rainscreen gap is ventilated below and above and the insulation behind is closed cell spray foam, so no moisture drives into the house.

Asked By Edward Mallett | Jul 24 17
3 Answers

Warm roof insulation: Ratio of air-impermeable (polyiso) insulation above deck to air-permeable (cellulose) insulation below

i have decided to convert my vented cold flat roof to an unvented warm flat roof to alleviate current moisture issues. The current placement of the scuppers will limit the amount of polyiso right foam insulation that can be placed on the top of deck; figure r20. We live in Chicago (zone 5) so this is the bare minimum required. Below the deck are 14 inch joists that are filled with loose fill cellulose insulation; I estimate the r value below deck to be r42.

Asked By Andrew Rothstein | Jul 25 17
3 Answers

Manual J, D, S

I am working on a major remodel of my 1950s house. The existing ducts are metal. I am looking for someone who can advise me on whether my existing ducts are properly sized and who can perform a Manual J and S since I will be replacing the air conditioner and furnace. I am outside Houston. I would prefer a 3rd party consultant over an HVAC company. I see some companies perform this service without a site visit.

Do I need a local company who can come to the house or can they perform these calculations accurately without visiting my house based on the floorplan?

Asked By Kasey Doggett | Jul 25 17
7 Answers

Indoor humidity levels: Magnitude of risk and solutions

I have some questions about the risk posed by humidity levels in my house and how best to address that risk. I have read lots of stuff on GBA regarding the humidity issue. Mostly I am looking for confirmation that I am on the right track. Sorry for the length of the following in advance.

Asked By Rob Shuman | Jul 25 17
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