Lowering Aluminium Door Frame

[Onoff]

The garage door, a reclaimed aluminium front door has always been a pita. Traversing the threshold with things like mobility scooters, always a mission resulting in it being bent over the years. I'm wondering can I do away with the wooden sill and just drop the ali frame down onto the black DPC? Ideally I'd like a level threshold. Not quite sure what the clear plastic is, the DPM maybe?

The ali frame replaced an original softwood door and has a couple of hardwood(?) packing strips either side where the ali door frame is narrower.

I might have to measure/draw a section through what I have at the sill.

View from inside:

From outside:

The header, obviously if I drop the door down there'll be a gap at the top. Looks aren't important, I could plate the front with aluminium and insulate from the back or bung a bit of timber in there.

 

[bricol]

As it appears to be above ground level so low risk of water easily flowing it, simply cut straight down either side, remove the aluminium and the wood cill, then rivet/bolt/glue/nail/weld an extension to the bottom of the door to fill the gap.

Local ish chip shop access up some stairs did similar to their uPVC door - too many people opened the door, tripped over the lower part of the frame and went down the steps in an unintended manner - so sawed off the lower part of the frame and screwed it to the bottom of the door.

 

[CompoSimmonite]

What about making a folded steel, say 3mm, double sided ramp that can be dropped over the threshold whenever it is needed ?