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2 Answers

Insulating a porch roof to create a four-season living space

I live in southeast Nebraska and I would like to turn an east-facing 19 by 8 ft. already enclosed porch with a concrete floor into a 4 season living space. there is no structure above the roof.

I don't see a way to vent the roof and would like to know if I used R-30 insulation and Reflex-it vapor barrier , with the proper dead air spacing and sealed it so very little if any water vapor could escape to get to the under side of the R-30 insulation , if I would be creating a problem with condensation.

Asked By Rick Eberly | Aug 25 15
17 Answers

Is it advisable to use nail base insulation panels over a roof insulated with closed cell spray foam?

We are renovating an old railroad station, turning it into a residence and are gearing up to put new roofing on the building. Built in 1888, the building has massive overhangs on all sides and the rafters are mostly 2x6s with 4x6s spaced about 8' apart supported by large brackets. We had planned to use closed-cell spray foam insulation in order to get the maximum r-value in the relatively shallow rafter bays. Also, we want to maximize the available head room in the second floor rooms. The underside of the roof will also be the ceiling with t&g beadboard installed directly to the rafters.

Asked By Jodi Gunderson | May 29 15
6 Answers

"Cycling" ductless mini-split

I'm working on my wife re: her dislike for the appearance of ductless mini-splits, but I have a question regarding their operation.

Asked By Brad VanVickle | Aug 23 15
1 Answer

Add external rigid insulation to a roof over a cathedral ceiling?

Yes, I know there are many resources on this topic. I’ve done a lot of reading on Fine Homebuilding and Green Building Advisor. I just can’t put all the pieces together.

We have a 30’x33’ 1-1/2 story cape cod with first floor living space, 2nd floor unconditioned space with knee walls and 2 doghouse dormers along the front. 25 years ago we added an extensive low-pitch shed dormer at the back vented to the ridge vent and installed drywall cathedral ceilings in order to add 2 bedrooms and a bath upstairs. No skylights, no recessed lights. We are in southwestern PA, climate zone 5.

Asked By Carolynn Friday | Aug 24 15
3 Answers

Rain screen at soffit detail

CMU house in zone 2.. Hot/humid. Unvented conditioned attic, Rigid foam around rafter tails to underside of roof decking. Cedar shingle sidewall. Verticle and horizontal furring for rainscreen.
Here's the question: There is a plate at top of the wall but due to the slope of the roof the horizontal soffit line falls below the plate line. For added support I would like to run the verticle furring up to and attach to the top wall plate. This means the top of the rain screen will terminate in the unvented soffit.
Do I need...and how do I accomplish ....the top rainscreen vent. Thanks

Asked By Robert Brown | Aug 24 15
7 Answers

What ceiling insulation to protect against ice dams in winter time?

I have very low ceiling less than 8 ft.
I don't want to lower the ceiling. But there are not enough space for insulation.
I wan to use Hard foam to insulate the ceiling having 4 by b joist.
There are two options.
1. Using 2 inch hard Foam(r-13 ) with radiant barrier. (Therefore, there are 1.5inch airspace above the radiant barrier )
I want to install the barrier to reflect inside heat to the room so that I want to make the ceiling being cold.
2. Uisng 2inch hard foam (r-13 )and 1.5inch hardfoam(r-9) together without the radiant barrier. No air space.

Asked By Mansig Yoon | Aug 22 15
13 Answers

How can I solve an uninsulated basement slab energy loss?

I built a supper insulated house on a foundation that was not. I currently live in climate zone 5A in central Illinois, the house itself has R30 basement walls, R40 first floor walls and R60 attic. Double stud framing, air barrier is at the house sheathing. The house itself is 4400 sq ft total of enclosed space, 2100 first floor and 2300 basement. At the moment my home is heated and cooled with a single point source ductless mini split on the main level with a Zhender ERV for mechanical ventilation. It performed pretty well this past winter and does well this summer.

Asked By Joseph Betz | Aug 19 15
2 Answers

Chainsaw retrofit / new overhang detail

Looking for opinions and pics of any added overhangs after old ones cut off. Roof is getting 6" rigid foam and will have 2x4 on top of foam with plywood on top of new 2x4. The 1.5" venting channel will be maintained soffit to peak to reduce possibility of ice dams.
I am in day 5 in my project and starting to stress over the soffit details of overhang and how to maintain the venting. I was planning on using vented drip edge. Any other suggestions?
attached pic is one of few I have found which uses a vented approach. Any links to other photos is much appreciated.

Asked By Dirk Gently | Aug 23 15
3 Answers

Freestanding kitchen sink cabinet recommendation?

Can you recommend a retail source for a free standing kitchen sink cabinet that is not MDF or pressboard? Thank you.

Asked By Mary Schwaba | Aug 23 15
22 Answers

Is it reasonable to use 3/8" PEX supply lines to all fixtures?

I am planning the plumbing system for my Net-Zero Energy home that is being built to Passive House standards. I will be using PEX tubing with a manifold system using home runs. I designed the house so that the bathrooms and laundry room are centrally located, making the supply runs pretty short. I want to minimize the amount of water and energy being used and low-flow fixtures provide plenty of water for my needs (2.2 gpm at sinks and 2.5 gpm for showers).

Asked By Gerald Blycker | Mar 11 14
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