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9 Answers

Skylights that sit flush but don't leak! Do these exist?

I am trying to daylight a currently unused attic under a shingle roof. Because we're in a historic district, we're not allowed to visibly alter the roof's silhouette (so no dormers or protruding skylights). My architect has proposed switching to a standing seam metal roof with thin glass skylights slotting into the metal seams (as seen in the attached pic). I'm worried that the lack of flashing will lead to leaks. Does anyone have experience with skylights that sit flush but don't leak? Or am I chasing a unicorn?

Your feedback much appreciated!

Asked By Nathalie Jordi | May 27 15
4 Answers

Recommendation for unvented cathedral ceiling retrofit from outside

I have a 1980's cathedral ceiling section (2x12 raftered) of my home with soft sheathing problems. Hence, I need to remove the sheathing and re-roof. Most recommendation are to spray foam against the sheathing, but this requires an additional interior drywall removal and the interior mess and disturbance I'd prefer to avoid. There are also recommendations for large 6+ inch of rigid foam to the outside of the sheathing, this causes difficulty with the home appearance at the eave and problems with adjacent roof lines that aren't cathedral.

Asked By David koeberlein | May 28 15
3 Answers

Confused — We are in the process of remodeling a home in upper N.H.

We have used Zip R on the exterior sheeting, Zip board on the roof sheeting and foamed the interior to R-27 wall and R-38 roof. We were ready to install radiant floor heat using warm board.

I am thinking mini split for the 2nd floor bedroom and return hot water for the main floor and basement.

Asked By Joseph Maraldo | May 28 15
1 Answer

Basement slab perimeter insulation

I was told that the updated code for Zone 5 required R-10 Foam for 2' around the perimeter of my basement. Local code has not updated to the modern one that states this, but I would like to do this anyway. My question is...does this mean 2' of foam going vertical against the footing, or 2' of foam horizontal butted up against the footing that goes around the inside perimeter of the basement? I am trying to understand what the benefit of just 2' does?


Asked By Nicholas C | May 28 15
17 Answers

Unvented roof underlayment and rafter bay insulation

Hi guys...first time poster, love the site its been a huge help. I've just finished framing my home in Montana and am ready to move on to the roof. It consists of multiple single pitch decks ranging from 1.5" - 2" in 12. Framing is 2x12 rafters.

Asked By Adeeb Hattar | May 27 15
4 Answers

Rainscreen venting connected to cold roof/back vented channel

Thoughts on connecting the vertical rainscreen vent channel to the cold roof/back venting channel on the roof or separating them.

I saw this last winter where the two channels are connected:
The solar washing of the siding caused subsequent ice damming even on a cold roof, due to the warmer air that comes from behind the siding was escaping up, under and out the roof peak. Anyone else encounter this?

Have you seen details that could eliminate this, but still provide an easy pathway for the vented air to escape?

Asked By Brad Hardie | May 28 15
7 Answers

Detailing flashing, waterproofing, and the various layers of exterior roof insulation and at the valleys and sidewalls

I am playing with how to integrate the different layers of thick exterior insulation, flashing and WRB at the top of the window/door trim, at the roof/sidewall, and at the valleys when using the PERSIST or ETMMS type methodologies. The window and door details are obvious when it comes to flashing right to the window or door flanges, but the other details are a bit more complex.

For instance:

Asked By brad hardie | May 28 15
1 Answer

Overinsulating or underinsulating?

We have a home built in 1986 in Columbus, Ohio (Zone 5). We are replacing our siding due to hail damage and plan to have the following layers on our home:

1. drywall
2. 2x4 walls with unfaced batt fiberglass insulation (R?)
3. polyiso 1/2"? - (old, some gaps, foil faced, says "R3.6" on the face)

4. 3/8" EPS w double foil face (~R1.5) - http://www.thermalbuildingconcepts.com/technical/propertySheet/ps-Physic...
5. Tyvek
6. Cedarmax insulated vinyl siding (R2.4) - http://www.proviaproducts.com/productdetail/vinyl-siding/cedarmax/

Asked By Chad B | May 27 15
1 Answer

Minisplit in tandem with a conventional heat pump?

A friend is getting ready to build a 2800 sq-ft retirement home in the hot and humid south, (Houston). His HVAC contractor is recommending a 5 ton, two stage heat pump. This is ~ the traditional 1 ton / 500 ft2 formula that prevails in this area with the added benefit of the two stage compressor. But 5 tons seems like a lot for a tight house and 2.5 tons is hardly the optimal dehumidifier in the light HVAC seasons. The house will be insulated with closed cell foam in the walls and under the roof deck. It is not what you would call an open floor plan.

Asked By Dean Wiley | May 27 15
5 Answers

Attached garage with steps leading into basement

We are building in SE Wisconsin. Currently just figuring out floor plan, in a rough design stage. Main level of house approx 1 ft above grade to approx 4 ft above grade on south side. Basement of house to be partially finished on south 1/2 of house. Attached garage on north side of house. Garage to be on same level as main floor of house. My questions deal with having a stairway in the garage leading to the basement level.

Asked By Dirk Denzin | May 26 15
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