[boddah]

What is the min R value of insulation behind pipes and what is best to use in a small amount of space.......bats and v barrier or styrofoam?

 

[Scuba_Dave]

My house is from the 50's & had R7 in the walls
These days its best to have at least R13

 

[Wildie]

What is the min R value of insulation behind pipes and what is best to use in a small amount of space.......bats and v barrier or styrofoam?

Styrofoam has a higher R value per inch than fibre glass.

 

[plumbob1234]

Code is different for each local. In Alberta it's 5 in. off any frost wall.

 

[plumbob1234]

Im assuming your not in Alberta though, since you would have froze to death long ago with only R-7 in the walls.

 

[the carpenter]

of course, it's best if you don't have water pipes in outside walls but if you must....
I'd use a high grade styrofoam, maybe the foilback stuff....not the cheap white stuff.
ALWAYS keep the pipes on the warm side of the vapour barrier!!!
If you can, keep the pipes exposed to the warm air in the house instead of drywalling over them. Anything to give your pipes the edge in those nippy winters.