Altering Cavity door unit.

[Oldhack]

Has anyone successfully made a Hume cavity door unit wider ?

I have a cavity door unit that for a 90mm stud wall, but I need it for a 100mm stud width.

Wall that I'm putting under a RSJ has to be 100mm thick so as to hide the RSJ inside the wall cavity, unfortunately this wasn't realized to after the 90mm unit was purchased.

I can order a 100mm unit from my supplier, but it want get here for at least a week, and my plasterer is booked in for the weekend.

[rwbuild]

Replace the 2 split jambs where the door enters with 2 pieces 5mm wider or simply glue a 5mm ripping of preferred timber species to the existing and the same on the rails, have had to do it a few times myself.
if your not to fussed about aesthetics you can just glue a 10mm ripping on one side

[Oldhack]

Two good suggestions rwbuild, I'm going to use them both, replace the split jamb, on the offset side, with one 10mm wider.

[riverbuilder]

You might have to pack the rails on one side to make the frame thicker, or there will be a defined bump in the plasterboard where the stud joins the cavity unit.

[Oldhack]

yes, whole wall is to be packed 10mm on that side.