door frame sizing

[bobby spray]

Hi, I have bought a new external door and frame for my garage rear access. I sent my wife to jewsons to get a new frame kit and door (smashed the other one breaking into the garage) The pre assembled frame she came back with is 845mm wide across jambs. I measure the hole width to be around 870mm. can I use this frame with packing or is 15mm per side too large to pack? What is the max gap that you can normally get away with?

Thanks
BS

 

[noseall]

The maximum gap should be no greater than the next size up. So, if garage doors work in 150mm increments and you are packing more than 75mm per side then you would go for the next size up.

15mm per side - no prob's, just use some architrave or bull nose skirt to cover. From a practical point of view, anything greater than 50mm per side would be difficult to fix but not impossible.

It is also possible in some scenarios to fix the frame at the back of the masonry and inset, thus allowing for a wider frame and door.

 

[JohnD]

and after the packing and fixing the screws, fill the gap with expanding foam (pray the surfaces with water first). It will fill the gap, prevent draughts, and stick the frame to the wall. To prevent the foam defacing the wall and the face of the frame, tape cling film tightly to then before injecting the foam. It expands a lot and is very sticky. You can trim it off with a knife once set.

You can cover the foam-filled gap with wooden trim. If you put it in place on the outside before injecting the foam, wrap it in cling film unless you want it to be stuck in place. The foam will then set in a nice tight fit to the trim. You can even put trim on both the outside and the inside, and inject foam through drilled holes.