replacing insulation


  #1  
Old 02-26-15, 09:30 AM
S
Member
Thread Starter
Join Date: Feb 2015
Posts: 256
Upvotes: 0
Received 0 Upvotes on 0 Posts
replacing insulation

I have a cabin that has 2 stories. The bottom story only is insulated with straw bale. it works incredibly well at moderating temperatures all seasons. But most potential buyers will never
go for it. So I need to replace it. I havent seen any products that have a hollow straw design similar to straw but synthetic. What newer alternative insulations do you know of that I might look into.I would like to avoid fiberglass because it doesnt have the qualities of a hollow straw
that seems to moderate temps. It will be covered with 3/8 sheathing and cement siding.
Spray foam is out because of the ridiculous cost. Those contractors have priced themselves out of business.
 
  #2  
Old 02-26-15, 09:50 AM
chandler's Avatar
Banned. Rule And/Or Policy Violation
Join Date: Dec 2005
Location: USA
Posts: 36,607
Upvotes: 0
Received 9 Upvotes on 8 Posts
Roxul Safe-n-Sound is a superior insulation material. It is rock wool based, flame proof, water proof, won't sag in stud bays, mold proof, and 3 1/2" will give R15 as opposed to fiberglas giving R13.
 
  #3  
Old 02-26-15, 10:31 AM
C
Member
Join Date: Jan 2014
Location: usa
Posts: 389
Upvotes: 0
Received 1 Upvote on 1 Post
I'm not sure of your construction. Is the straw bale designed to be structural or????

Will the new insulation be going between framing members? Rock wool is fire proof and a good insulation but like all fibrous materials can retain water between fibers. Not a concern if it won't get wet. Foam, is expensive but you have to realize that the material is very expensive and the equipment is also pricey so contractors need to recover those costs when selling a job.

Is it feasible to install foam sheathing beneath your wood sheathing? Also, 3/8" is not a suitable sheathing IMHO.

What degree of temperature differentials are you designing for? How well air sealed is the structure? A few more details may help in getting to an effective conclusion.
 
  #4  
Old 02-26-15, 04:49 PM
S
Member
Thread Starter
Join Date: Feb 2015
Posts: 256
Upvotes: 0
Received 0 Upvotes on 0 Posts
the straw is not structural. There is framing of sorts in the wall and I can adjust it to suit.
the current bays are 14 inches so I could leave an air space between the insulation and the sheathing if needed.
How much is this wool stuff???? Can I get it at Home Depot??
Our climate is bone dry and from -20-+ 90F depending on season ..the straw could keep the bottom floor a constant 62 degrees in 85 degree heat with no AC or fans.It sits on a slab
ground level and insulated in the ceiling too. And there is no musty smell in our climate.prairie/desert.
 
  #5  
Old 02-26-15, 05:56 PM
C
Member
Join Date: Jan 2014
Location: usa
Posts: 389
Upvotes: 0
Received 1 Upvote on 1 Post
Rock wool will run something in the $ .75/sq.ft. price for 3", r-12. Generally, it is available at HD or Lowes.
 
 

Thread Tools
Search this Thread
 
Ask a Question
Question Title:
Description:
Your question will be posted in: