Can I cut my UPVC door to make it smaller?

[sunny2day]

I've had a new concrete floor put in my kitchen but its higher than the old one. I want to use re-claimed quarry tiles as flooring but the thick tiles will stop my UPVC backdoor from opening. Can I cut the bottom of the door off? If I can, how will I seal the bottom again? I can't afford a new door and I don't think moving the hinges will create sufficient gap, please help!

[heathfield]

The problem with doing this is that the door will have a metal core that you might cut into, thus ruining the door.
Cleversod's idea is better - but as it's a back door it means the wall is likely to be structurally supporting. If so, to knock chunks from the top of the doorway is a job to be left to professionals. This will cost, and may be a false economy A new made-to-measure door (after very careful measurements!) is perhaps the simplest and best answer.

[sunny2day]

Thanks for the advice, I thought it wasn't a good idea to cut it but I thought I'd check what people thought.
As it happens by Mum's come up with a perfect solution - have my beloved quarry tiles but leave a space where the door opens, put beading around the edges of the tiles thus creating a 'well' and fit a door-matt or wrought iron grate into the gap. A much cheaper & less complicated solution. You can always rely on Mums!