Do any manufacturers supply R-25 batt insulation for 6" studs?
I have seen R-19 or R-21 , but am looking for high performance Fiberglass Batt Insulation information.

 

R-21 is the highest R-value you can achieve for a 2" x 6"
wall....utilizing a fiberglass batt

Rather than try for a higher R-value in the wall, it is far better to try and stop air infiltration...

methods to consider

Foam seal around window and door openings as well as behind all electrical outlets on exterior walls, do not install more than 1/2" thickness at window and door openings..

caulk all doublers and at the plate.

If you address these areas you will achieve much better results than trying to increase the wall insulation to R-25...

Good Luck

Jim

 

Increasing to a "R" 25 is not cost effectve. Fiber glass is about 10% efficient so the add'l amount would probably never pay for it's self in fuel savings.

If you are planning to build, then I would recommend using 2x4 for the same reason.

If you are going for the max then a radiant barrier (97% efficient) would be far more effictive. Contains no cancer causing fibers or chemicals and you don't have to worry about killer mold or condensation. It is also a superior vapor barrier. You can install a two or 3 layer material in the ceil'gs and walls. You could reduce your heat $ about 33% and cool'g about 50% +. (Mo. sav'gs) You can also reduce the size of the a/c and furnance.

For more radiant barrier info, enter into your search engine "radiant barriers" or "reflective insulation".

If you have any $?'s about method or material source, let me know.

Thank you for considering my opinion.