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21 Answers

Daylight basement insulation - exposed XPS and other questions


I’m about to insulate the floor and 2 walls of my walkout/daylight basement, and I was hoping to get a little advice on a couple of points I’m not clear on. I’ve researched quite a lot, and learned a lot on this site, but I’m still not sure on a few things. Any help is much appreciated.

In General questions | Asked By Aggy Clayton | Oct 28 16
7 Answers

What direction should I go with my new/used home?

I purchased a 23 year old home to accommodate my growing family. It was constructed with double wall construction, wood foundation, Envirovent system etc. We live on Nantucket Island.
I am planning to install a mini split system and have questions on further improvements, possibly solar, that are upcoming.
My first inclination was to update systems based on the recommendations of local hvac contractors until I realized that my new home is unique and that I might need specialized consultation from someone more familiar with this "type" of home.
Any advice or suggestions are welcomed.

In GBA Pro help | Asked By todd stout | Nov 29 16
7 Answers

Insulate basement wall with half wall, brick exterior, and dimple mat

First of all, this site is incredible! I've spent countless hours reading through threads related to my current project and many others. Thank you all for providing this amazing resource.

In Energy efficiency and durability | Asked By Carlos Moreno | Nov 28 16
14 Answers

Fireplace in tight house

I have just starting building a new house which will have an Isokern fireplace. The hose will be relatively tight with ZIP sheathing and spray foam insulation. Besides opening a window/door to allow for the fireplace to adequately draw, what is recommended for sufficient air to feed the fire. (Please, no comments re fireplace is not practical in a tight house, etc.) Isokern sells an outside air vent but not sure if that is sufficient or the best way to go. http://earthcore.co/product/outside-air-kit/


In Energy efficiency and durability | Asked By Richard Marks | Nov 29 16
16 Answers

Exterior foam wall assembly without interior polyethylene

I am building a Net Zero home in Edmonton, Alberta Canada and plan on using 6" of EPS or XPS rigid foam on the exterior of a traditional 2x6 wall sheathed with OSB and filled with Roxul batts resulting in about an R-40 wall.

The building code here calls for polyethylene on the interior and a maximum 1/3 rule for insulation on the exterior however the recommendation on this site is at least 4" of exterior rigid foam and no poly for a wall like this(I assume my climate zone is 6). How can I convince the city to accept my design and how can I ensure air tightness without poly?

Thank you.

In Energy efficiency and durability | Asked By Sheffie Kalat | Nov 27 16
7 Answers

How to insulate a screened porch floor

I am looking to insulate the floor of a 3-season porch that is outfitted with removable sashes that will be removed for the entire summer season, thus exposing the floor to some blown-in rain. The sashes will be reinstalled in the fall so that the porch can be used in the fall and spring and will be opened up to the main house to benefit from the heating system in the house.

In Energy efficiency and durability | Asked By Elizabeth Slotnick | Nov 28 16
1 Answer

What is wrong with my gas fireplace?

We have a gas fireplace insert. It will not stay on if the solid glass door is on it. If we remove the glass it will work. We've had a partial inspection done on the control and logs. They seem to think it is not getting proper air ventilation. Would this be due to improper install of liner? would they be something clogging up the liner?
Any thoughts would be appreciated. Our chimney is approximately 40 ft. so we are having a hard time finding someone to look at it.

In General questions | Asked By Linda Wachs | Nov 29 16
4 Answers

Frost on outside of triple pane window

Every so often I notice frost/water (depending on outside temp) developing on the outside pane of my triple pane windows. It's infrequent but will mostly notice it early mornings. Actually, as I sit here this evening (68F indoors, 28F outdoors) the exterior of my windows are frosting up a bit. Interior pane is warm to touch. No moisture problems inside. Air exchange keeps interior moisture around 35-40% in the winter. Moisture (minimal-in bottom corners) only forms on interior windows when it's -10F and below. Thoughts? Thanks.

In General questions | Asked By Matthew Michaud | Nov 28 16
7 Answers

New earth sheltered PAHS construction

I would like all opinions regarding my new home construction project. I have a full 3 days experience learning Sketchup and have managed to put several ideas on paper. Please review my plans...and pick holes in them :). I don't guarantee to change my mind, but I do promise to research varying opinions thoroughly and supporting data would be appreciated.

Mixed humid climate Missouri 39 deg latititude
CoMo HDD 5173
CDD 396
Sunny days 195
Humidity ave 70% 83% AM, 56% PM
111 days rain for 46"/yr
10 days snow for 14"/yr

In Plans Review | Asked By Laurel Davison | Nov 28 16
4 Answers

Interior walls acting like exterior walls

New construction in zone 5. We have 3 interior walls that we have to build up still where the vaulted ceiling meets the flat(see pic). We are planning unvented on the vaulted side (3" closed cell, and fill the rest with cellulose, but just blown in cellulose on the flat ceilings. How would you recommend I build and insulate this wall? I figure I need to treat it like an exterior wall, so drywall, studs filled with fluffy and 3" of rigid foam?(that is what we are doing for our other exterior walls). Thank you in advance.

In Energy efficiency and durability | Asked By Michael Brackett | Nov 29 16
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