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12 Answers

Exterior Insulation on Cinder Block Walls

I have been through many articles talking about exterior insulation techniques, and insulating the exterior of foundations. My house is a little unique, and I'm hoping that someone can offer some insights/guidelines on how to handle things.

Asked By Jameson Taylor | May 18 18
8 Answers

“Picture frame” method for outie windows

i am installing outie windows in a house with 4” of exterior rigid insulation. the windows are all triple pane in the following sizes: 24” x 24”; 30” x 30”; and 32” x 64”. the method that i would like to use to install the windows is mentioned in the article :

"Install a picture frame of 1x4 lumber, installed on the flat, on the exterior surface of the rigid foam. The 1x4 picture frame is screwed through the rigid foam to the sheathing and framing."

Asked By Loretta Gurr | Apr 28 18
6 Answers

Insulating hot water pipes?

Hi folks -
At some point we'll get a roof and then be able to close up the walls. While we wait - I have long thought about wrapping our hot water pipes with insulation. At the local big box - I have a couple option: 1. Rubber, Foam, and a fiberglass product.

- What are the thoughts on insulating hot water pipes? Any risk of condensation that would be problematic?
- We have installed a hot water recirculation loop - insulate that?
- Probably too big to insulate - but we also installed a drainwater heat recovery pipe...

We are in northern Virginia.

Asked By Adam W | May 15 18
5 Answers

Can I re-insulate my cathedral ceiling using the stack-of-pancakes approach with a vent?

I have a gable roof with a cathedral ceiling built with 2x8 rafters 24” on center. There is a ridge vent already installed and the roof assembly to the north of the ridge has soffit vents while the assembly to the south ends in the main attic space which is also ridge and soffit vented. I have spent several hours reading through the “musings” and other online resources and decided to move forward with the stack-of-pancakes method.

Asked By Trying harder | May 17 18
11 Answers

Conditioned Attic - Roof Construction in ICF Home


We are building an ICF home in northern Indiana, climate zone 5A. It will be about a 3k sq ft ranch with a 1k sq ft unfinished basement. Exterior walls will be made from Build Block, using 4" concrete forms above grade with thicker forms below. The builder tells me that they are effectively R-50 walls.

Asked By user-7022224 | May 11 18
3 Answers

Slab are not designed for comfort and R-value?

Slabs are terrible to walk on--at work we have concrete floors. My legs and feet hurt after a few hours.
Yet I can walk my dog for an hour on ground and my house is on a joist floor and its all good. So on my addition--a slab is better than a crawl space of 36". I have seen where you can put treated sleepers in and fill between with sheet foam--but wouldn't that make it stiff by eliminating flex? has their been any work done on measuring floor give when you walk on it? Is their a way to replicate a wood floor on the slab that can be rated?

Asked By Scout159 | May 16 18
5 Answers

Alternative to SIP roof?

Hi. I'm building a cabin in Wa State and the designer has spec'd a SIP roof. I have two concerns...

- First, how to finish the visible underside of the SIPs? The SIP company (Premier) apparently only offers a secondary ACX plywood lamination, which I don't care for. Is there a common method for producing a finished ceiling with SIPs?

Asked By user-7070878 | May 13 18
4 Answers

Existing basement framing against concrete

We are looking to insulate our concrete basement foundation walls and the 18" wood framed area between the foundation top and the bottom of the floor above it that includes the sill plate. We are settling on closed cell spray foam.

When the house was built the framing for the exterior basement walls were set up against the concrete foundation. There is anywhere between 0 to 1/4" between the studs and the concrete depending on the studs and the texture of the concrete forms.

Asked By tyman00 | Apr 11 18
4 Answers

Unvented vented roof with exterior rigid insulation

Hey All,

I am doing an energy retrofit on a Zone 5 simple box gable roof. Part of this calls for redoing the roof. I am sold on the exterior rigid foam idea to cut down on thermal bridging and also since my roof slope is very low and the eaves are shallow.

Code calls for R38 but I want to shoot for about R50. The planned assembly going upward is:

1. R20 of fluffy between upper truss cords
2. Structural sheathing with taped seams
3. Air barrier
4. First layer of 3" polyiso rigid foam
5. Second layer of 3" polyiso rigid foam with staggered and taped seams
6. Roof underlayment

Asked By jetlaggy | May 12 18
1 Answer

Attaching LP Smartside to ICF house

I'm looking for detailed information on how to install LP smartside on an ICF house. If anyone can help me out, the more information the better.

Thank you,

Asked By JBICF | May 12 18
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