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3 Answers

CLT + Wood Fiber + Cork Facade

I have been through the ringer here with these walls and have circled back to what seems to inadvertently simulate an actual tree buildup.

(Heartwood --> Trunk --> Sap --> Cambium --> Bark --> EXT) is replaced by (INT --> Cross LAminated Timber --> Air Barrier --> Wood Fiber --> Cork --> Ext).

The roof assembly is a bit different, replacing the cork with an air gap (is this necessary?) plus sheathing and either TPO or EPDM.

Asked By Ethan T ; Climate Zone 5A ; ~6000HDD | Aug 22 17
20 Answers

3/12 pitch roof insulation

Hi all.
I sent a question and got a reply on a 2/12 pitch roof.

I have an architect working on my plans now. It is a single-slope roof at the widest part (of 32 or so feet).

I originally was going with 3/12 pitch, but he thought 2/12 would be a lower roof at the tall end, so I said fine!

Now, looking at the problems with 2/12, I asked to go back to the 3/12 pitch. So: If I go 3/12, would I (or should I) use R-60 fiberglass? It will have 24 in. parallel trusses.

Would I still need a cupola? (Zone 6, lower Michigan.)

This is TMI for my small brain...


Asked By Robertsoave | Aug 19 17
11 Answers

Limited budget: Dense-packed cellulose or Zip R-3?

We are building a custom house in central Maryland, which is in Climate Zone 4 and has adopted the 2015 IECC.

Our budget is already stretched pretty far, so it looks like we can only afford one of these upgrades to our walls:

(1) Dense-pack cellulose insulation (instead of inexpensive fiberglass batts - exact R-value unknown)

(2) Zip R-3 (instead of regular Zip)

Which of these options would the Green Building Advisor Community recommend?

Asked By User-6890381 | Aug 21 17
2 Answers

Electricians: Are copper main water lines still used for the main house ground?

I will be running my main water line under the footing very soon, and although I have selected Pexa for the main 550' run, I still have the option to connect it to a 12' piece of 1 1/2" copper pipe to make the through slab section/main ( I am just running a 3" abs pipe under the footing right now to allow connections at a later time)

Asked By Mai Tai | Aug 22 17
1 Answer

Thoughts on Legend HyperPure pipe

I've been looking for a "greener" pex alternative that does not leach and type of chemicals/taste into the water.

After doing some research last night, I learned about the pex alternative, Hyperpure, on this GBA article:
Making The Best Pex Connections

Asked By Grey Wolf | Aug 22 17
25 Answers

High humidity in between floor space in 2-story home in Zone 3A

Our home has a "crawl" space in between the first floor and second floor, all of our AC duct which is insulated is in this area. It appear to be well insulated, and is the same temperature as the house most of this time, within 1 degree or 2.

The issue is the humidity in this area is 30% higher than inside the house most of the time. The humidity in the house can be as high 58% in this humid season right now, but in the crawl space it is as high 89-90%. It seems like it should not be this different?

Asked By Momndad | Aug 18 17
7 Answers

I would appreciate a review of an air-source heat pump quote

zone 7 Kenora Ontario, Canada.

I asked for a quote for an ASHP unit that would work for the time being as well as in the near future when the house is expanded...

Some background....

1-short term.. (with the building as is)

-to heat and cool my existing home, 850 sq ft 2x6 framed 20 yr old bungalow on conditioned 5 ft insulated crawlspace...

I completed an online manual J about a year ago and determined as best I could a heat load of about 25000 btu.


Asked By Tim Brown | Aug 19 17
7 Answers

Advice on tight building

I have my house rough framed, we are framing out the roof now. Climate Zone 2 ( Just north of Austin). 2x6 conventional framing 16 on center, and has the typical double headers around windows etc. I am nearing having to lock down my decisions on sheething, insulation etc. I have been considering using Zip R for a couple reasons.

1. breaks my thermal mass, that I have plenty of
2. Weather and air seal.

It is anything but cheap, I am looking probably 7000 for the 1inch.

However I am looking at other options

Asked By Sleaton | Aug 15 17
10 Answers

Mild climate; expensive cellulose — What to do?

I am getting ready to go to Engineering for a new house in Raleigh, NC.

HDD - 3247 and going down....On border of zone 3 and 4. Technically in 4 but 20 miles from the 3/4 border.

Being in the South, everyone worries about cooling but we usually have 3x the cost in heat (based on last energy audit).

Asked By User-6902085 | Aug 18 17
7 Answers

Crawlspace with cellulose insulation - Go or no go?

Greetings GBA folks,

From Columbia SC. Please help determine whether blown in Cellulose between the floor joists is recommended.

Here are the parameters measured in the 20 year old crawlspace:

1. Current moisture content of the joists is at 18 %
2. Relative humidity is at 72%
3. Foundation is drained professionally well down to the footers - no current issue with water, or termites
3. Crawlspace is awaiting contractor to install 20mil vapor barrier to 1400 sqft dirt floor area

Asked By FusionHome | Aug 20 17
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