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6 Answers

Foam sheathing insulation on basement block walls

Building a new home in Syracuse NY. We will have two bedrooms in the finished basement (not walk out but large egress windows). I want to use foam sheathing on the concrete block walls - primarily as a vapor retarder but also for it's insulating value. I have read differeing opinions on the ideal permeability rating for foam in this situation. BSC says to keep it permeable but I have read elsewhere (here maybe) to use impermeabile. I have my eye on 1" XPS because Lowes has it in stock.

What do people recommend? Thanks

Asked By david schreiber | Oct 23 16
3 Answers

Upsize my generator or add propane backup

Rebuilding my home after a loss.
Pole-mounted solar array survived (~14,000kwh/year)
Energy efficient construction/design.
Manual J puts heating load at just under 24k.
Climate zone 5 (but right near the edge of 6).
Sadly, radiant heat is a design requirement.
(We had it in our old house and the rest of the family is reluctant to give it up.)
No access to natural gas.
My hvac supplier is a very talented mechanical engineer with years of experiencing installing solar/gshp/ashp. (and a family friend)

Asked By Nathaniel Hieter | Oct 27 16
0 Answers

Devil's Triangle & Cathedral Ceiling Insulation

I've been reading this forum for a long time now and am at the point where I'm beginning the work.

I have a 1.5 Story Cape. Roof is vented, I am unable to build an unvented roof at this time.

I have derived a plan to insulate the kneewalls and sloped ceiling but am concerned that my plan may lead to a moisture build up. Any advice would be greatly appreciated.

Sloped Ceiling (Roof Sheathing Down):
1) Continuous and Sealed Ventilation Chutes from the Unconditioned Triangle to the Attic Space
2) Fiberglass Batt Insulation

Asked By Brian Beck | Oct 27 16
17 Answers

Is it possible to repair a SIP roof that is rotting?

We built an SIP home using panels from ACH Foam Technologies. The roof was installed according to manufacturers specks. The panels were OSB on both sides of expanded polystyrene insulation, about 7" thick. Block splines were installed with the prescribed Do All Ply sealant. This design had space between the lines of calk for air to move vertically. The OSB has begun to de-laminate at the seams visibly under the shingles.

Asked By Allan Poole | Sep 6 15
81 Answers

While I love radiators, I hate using fossil fuels

I live in an 1890 Victorian in Southern Pennsylvania, heated by oil. While I love radiators, I hate using fossil fuels! Is there a way to use green technology to use less oil? My methods to date have been uncomfortable - installing a wood stove.

Is there a way of boosting the boiler with green energy? Would geothermal help? I'm newly divorced and ignorant about systems!
Thanks, Susan

Asked By Susan Hanway | Aug 28 16
5 Answers

Insulating in basement ceiling under porch

Hi All,

I apologize if I am asking a common question. Rest assured I did a lot of research before coming here to no avail.

So here is my situation. My semi-finished basement (concrete floor, concrete walls, etc.) is divided into three sections:

1) Section 1 is under our covered porch
2) Section 2 is under our covered porch
3) Section 3 is under the rest of our house.

I am wondering whether it is a good idea to insulate the ceilings in either Section 1 or 2. I know section 3 is a no-no because it is covered by our house which is heated.

Asked By Briz Katzman | Oct 27 16
2 Answers

Design help for combined DHW and Space Heating


I am finally at the point of my remodel where I can get the mechanical design completed and so I'm following up on my earlier post 'Radiant heat design details - Bosch or Navien combi boiler?'.

Asked By Torsten Budesheim | Oct 26 16
4 Answers

Best practice for stone siding over stick-built walls?

We are planning to apply 4 inch thick rubble stone siding over the lower level of our daylight basement home. We had originally planned for ICF at the lower level walls, partly to mitigate rain water and inward vapor drive risk brought on from the stone (which is south facing). As it turns out the ICF represents a substantial cost increase and we are considering alternative wall options (stick-built) for the above grade portion of the lower level wall.

Asked By Sean Hembree | Oct 22 16
6 Answers

Insulating a 2x6 cathedral roof

Just read "How to Build an Insulated Cathedral Ceiling" trying to apply to my gut rehab project.
Zone 5a, house has a hip roof framed with 2x6. When I tore drywall off, found vented eaves with no venting on roof. Insulation was 6" fiber glass bats tGN#?with no air channel space. Roof has brand new shingles so I want to insulate from below. I am thinking non-vented roof, fill 2x6 void with closed cell foam and then install 2" foam on studs for thermal break. Does this sound like correct strategy? Should I install vapor barrier below foam board before drywall?

Asked By Steve Karkau | Oct 23 16
7 Answers

Duct Blaster testing

We are building a new home outside of Syracuse NY. Apparently the building codes around energy efficiency have just changed however our building permit was issued under the previous code. Anyway our builder has asked his HVAC sub to do a duct blaster test on our duct system in order to determine whether the standard duct installation measures (taped seams) will be enough to meet the new code. If not they will presuambaly take additional steps for future builds, though not necessarily for mine.

Asked By David Schreiber | Oct 27 16
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