Q&A Forums Home » Spray Foam Questions & Answers » Roofing Q&A Login User Register Search
Search Forums: 
 

Q&A Forums


[ Post New Topic  |  Post Reply ]
Author Comments
timheger

Q&A Forums Registered User
Posted: 1/21/2007 9:04 AM EST

Related Link:
Cabin Photo's

Reply

Log cabin roof
I am building a log cabin and I need to put a roof over the exposed tounge and groove sub-roof. Right now the traditional method is to frame a 2x12 structure on top of the tounge and groove. The 4x10 rafters which support the exposed tounge and groove provide all the required support so the 2x12 structure is just to provide for the standard roll insulation. See photo's on blog site listed.

My questions are:

1-Is there a spray foam solution that will provide the required R38 value that I can spray onto the existing structure?

2-If there is a product that I can use - what kind of framing is required (2x4, 2x6, etc) will I have to build over the existing sub-roof?

3-What foam product did you use and where can I buy it?

Thanks,

Tim

Tom  

Q&A Forums Registered User
Posted: 1/21/2007 11:30 AM EST

Reply

RE: Log cabin roof
I have done some built up roofs in the past. I use 2x6 lumber on end and screw them down to the roof rafters. You need long screws, I use ten inch screws and predrill the 2x6s. You can get a r-38 in that cavity with ridgid spray foam.

timheger

Q&A Forums Registered User
Posted: 1/21/2007 4:48 PM EST

Reply

RE: Log cabin roof
Thanks for the reply - did you frame the 2x6's 24" OC?

Tom  

Q&A Forums Registered User
Posted: 1/21/2007 5:24 PM EST

Reply

RE: Log cabin roof
Yes the 2x6s were 24" oc with a tin roof on top of them.

foamdude

Q&A Forums Registered User
Posted: 1/22/2007 8:16 AM EST

Reply

RE: Log cabin roof
"Is there a spray foam solution that will provide the required R38 value that I can spray onto the existing structure?"

yeppers!! closed cell ~r6.5 to an inch...most applicators will tell you 4-5" will be plenty of closed cell as you are ~94% thermal efficient with this product in this appliction...
open cell ~r3.5/inch,,but i personally would apply in the 8-10" range to obtain good rvalue and great thermal performance...

consider a layer of board stock under the tin roof,,over the top of the 2x12 rafters to stop the thermal bridge effect of the rafters...

nice blog..frame on..

since you are

Olger  

Q&A Forums Registered User
Posted: 1/22/2007 8:55 AM EST

Reply

RE: Log cabin roof
"1-Is there a spray foam solution that will provide the required R38 value that I can spray onto the existing structure?" Yes.

"2-If there is a product that I can use - what kind of framing is required (2x4, 2x6, etc) will I have to build over the existing sub-roof?" 2x6 is adequate, as Tom suggested. Use Rigid foam (closed cell).

"3-What foam product did you use and where can I buy it?" You will have to locate a contractor in your area.


all the best,

olger

Tom  

Q&A Forums Registered User
Posted: 1/23/2007 2:09 PM EST

Reply

RE: Log cabin roof
I think the built up roof is the most difficult and time consuming to do especially on a 12/12 pitch, but is very rewarding when finished.
Have fun and be careful up there.

Jump To Forum:
Jump To Board:

Q&A Forums Home
Contact The Q&A Forums Editor

Ads by SprayFoam.com