Help with insullation

[64auto]

My contractor put the insulation in my 34 x 60 two story garage yesterday.
In the first floor they used r30 in the ceiling and r19 in the walls. Here is my problem. Upstairs they used r30 in the ceiling but the end walls and the knee walls they used r13. Is there a reason for this or are they just cutting cornors? Allso they did not insulate the celing behind the knee walls.

Thanks

 

[Northstar9126]

Assuming you have a stick built garage with 2X6 studs, the contractor used R19 in the walls because that is all that will fit in the stud bays without compressing the insulation. If the knee walls are insulated there is no reason to insulate the roof behind it as it is not a heated space. No he didn't cut corners.

 

[GT350RC]

and isn't R13 for 2x4?

 

[64auto]

Assuming you have a stick built garage with 2X6 studs, the contractor used R19 in the walls because that is all that will fit in the stud bays without compressing the insulation. If the knee walls are insulated there is no reason to insulate the roof behind it as it is not a heated space. No he didn't cut corners.

All of my walls are 2x8 studs downstairs he used r19 but upstairs he used r13. Will this cause a big lose of air or heat?

 

[Northstar9126]

You might want to check those studs. 2X8's would be extremely hefty to stud up a garage with, not to mention expensive. As far as the R13 upstairs, are you refering to only the knee wall or are all walls insulated with R13? If it is just the knee wall it may be that it is framed using 2X4's, 2X4 walls call for R13. If the end walls are, as you say 2X8's, or as I suspect 2X6's they should have the R19. If that is the case then you do have a valid gripe as they will most certainly not be as efficient as they could be.

 

[Northstar9126]

and isn't R13 for 2x4?

That is correct. Assuming fiberglass insulation. There is I believe some fiberglass insulation that claims slightly higher R value for the same thickness. I've never used it.

 

[JMURiz]

A picture of the areas you are wondering about would help a lot. I'm guessing the knee-wall you are talking about is for a gabled roof and is only 3' or so high until the slope starts, right? If that's the case I think you'll be fine.

I think they make R-15 for 2x4 studs as well, but it's harder to find.