stiff insulation doubling as support?

[stdavid]

Hi...so i find out the "add on" has an exterior wall of 2 x 2. It would be easier to lay stiff strong (if there is such a thing) insulation foam boards over the 2x2's and then putting my wallboard on top of that. Would this idea of using this type of insulation as extra roof support work? I will be putting 1/2" wallboard on top of the insulation. Otherwise, can I put the 2x4 perpendicular "against" the 2x2 to stop the wall from jutting into the room (small) any further than it already is? After all, I do need to attach my wallboard to something. There is that to consider. Panelling was used previously. thanks

[David Oxhandler]

Foam board will not add any structural support.

Placing a 2x4 perpendicular to the existing 2x2 will add some support but not give you the same strength as a conventional 2x4 wall.

Wall studs must be turned so that the short side is to the inside (and outside) of the wall. If you turn them sideways you will not get the maximum support strength.

I doubt you will have any problem attaching 3/8 Sheetrock to the existing framed wall.