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20 Answers

SIP roof issues

Hi Everyone.

I was listening to Mr. Holladay on the FHB podcast and started getting nervous about my SIP roof built 3 years ago.. We live in central Washington and the climate is pretty cold in the winter (mid 20's) and hot in the summer (upper 90's). The humidity levels are low year round. We get about 2-3 of snow on the ground by February. The roof is 1/2:12 pitch and is 64'x32'. The bottom seams of the panels were taped, although the tape didn't seem to stick all that well. The humidity in the house is around 28-32% year round. The ceiling is painted drywall.

Asked By Matt Melton | Feb 17 17
2 Answers

Roxul Comfortboard to create cathedral ceiling baffle?

Hi all -- thanks for taking the time to read this.

I'll be building a new home this spring in zone 6 (northern Vermont) that will have cathedral ceilings. I've read a lot about the best way to do this in my climate (thanks for all the info on this site, Martin) and I've settled on what seems like a safe bet: taped drywall and vapor retarder paint, dense pack cellulose (16" or so), homemade baffle, 2" airspace, plywood sheathing, underlayment, metal screw down roof.

Asked By Blake Cote | Feb 23 17
7 Answers

National Fiber in Belchertown, Mass.

Does anyone know how to reach National fiber in belchertown mass?
Emails to them bounce and their 1 800 number goes to some vacation service...
I don't know if they are hacked, or what.
I can't imagine they went out of business...
Anyone have a cell phone for one of the reps?

Asked By Scott Mangold | Feb 21 17
12 Answers

Installing LP Smartside over foam and 24 inch centers

We’re building a new home (SW Virginia) with 2x6 studs on 24 inch centers. We had hoped to use 1.5 to 2 inches of EPS rigid foam to the exterior of the sheathing, then 3/4 inch x 4 inch plywood furring strips, then LP Smartside lap siding. We knew we had to use the 76 series Smartside product for the 24 inch centers. Then I discovered that LP’s installation instructions specify 1.5 inch x 3.5 inch furring strips for foam greater than 1 inch in thickness, so I guess that would basically mean a 2 x 4 stud for every 2x6 stud in the wall.

Asked By William Costello | Feb 17 17
5 Answers

New home wall assembly

I am currently designing a new single-family home in Northern Virginia (Zone 4, Mixed-Humid Climate) and am looking for some feedback to my tentative plans for wall and roof assemblies. I am not trying to build a passive house, just a more durable house. My primarily concern is controlling/managing air and vapor movement.

Walls: 2x6, 24" oc w/ open-cell spray foam insulation in the cavity, ZipSystem R3 sheathing on the exterior and 5/8" drywall foamed to the studs.

Asked By Michael Winn | Feb 11 17
7 Answers

Sizing mini-split for cooling & humidty control.

We are building a small cabin in CZ 6. It is a seasonal cabin that will see limited winter use so while we do want a mini split that will heat the space we are not concerned if it ends up being undersized. There is so much free firewood in the area that the Forest Service and private land owners often burn huge slash piles in the winter just to get rid of it. I also have access to hundreds of board feet of free hickory cut-offs from a local cabinet shop. So we'll have a wood burning stove regardless.

Asked By Chris Harper | Feb 23 17
19 Answers

HTP Phoenix Light Duty paired with Lifebreath Clean Air Furnace (downdraft)

I want to replace the atmospheric water heater (interior to my house) with sealed combustion. I also wanted to replace the 80% furnace that sits right beside the WH interior to the house. I learned early from GBA that inside combustion is to be avoided.

Fast forward...I am looking at the HTP Phoenix Light Duty + Lifebreath CAF (downdraft). I am in the Seattle, WA area in a 1950's rambler.

Asked By S K | Jan 11 17
4 Answers

Pink sill foam vs. green treated lumber

On interior walls sitting on a concrete slab. Which would be better? Green treated lumber or standard lumber sitting on top of the pink foam sill sealer membrane?

The treated lumber has borate/chemicals in it while the foam sill sealer doesn't put off VOCs.

Which works better, is longer lasting and healthier?

Asked By Peter L | Feb 22 17
7 Answers

Zip System R-Sheathing

Quick question about Zip System R-Sheathing.

The concept of a REMOTE wall, where exterior insulation is used to ensure that the structural sheathing stays warm (and thus dry), makes perfect sense to me.

The Zip System R-Sheathing is a compelling product because it saves several steps by installing all the necessary wall components in one go.

HOWEVER, from the pictures on their website, it looks like the Zip System R-Sheathing has the WRB on the outside, followed by the sheathing, followed by the insulation. So, doesn't this mean that the sheathing is cold?

How does that work?

Asked By Matt Culik | Feb 16 17
10 Answers

Modified Perfect Wall, What happens?

When looking at Joseph Lstiburek's Perfect wall system; What happens when we change the order of some of the layers. I am looking at the Zip-R Sheathing produce which would place the Water and Air control layers outside the Thermal Control Layer. Are there any concerns with this. The only downside I can see is that we no longer get the opportunity to use multiple layers of Insulated Sheathing with staggered seams.
Would this change depending on the climate region?

Asked By Jeff Classen | Feb 22 17
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