Fitting a Firedoor to a door with a metal threshold

[NeilPalfreyman]

I have a late '60s house with an external door that has a metal threshold strip sunk into the concrete door step.

A garage has since been retro-fitted so this external door is now an internal door. Whoever did the garage conversion didn't change the door to a firedoor and I want to correct this now.

But I'm having great difficulty in finding a firedoor that will let me rout a 15mm rebate off of the bottom to clear the threshold strip and am looking for options.

Anyone have any experience of removing such a metal threshold? I thought of a disc cutter but it wouldn't get into the corners. Is it feasible?

Alternatively does anyone know where I can get a firedoor that would have a big enough frame at the bottom to allow me to take 15mm off of the back edge.

 

[pinenot]

Often these strips are simply pushed in to the concrete and as such can be readily removed, but first we need to ascertain how beefy this metal strip is.
If you can, try hitting down into the concrete with a club hammer, a good smart smack should tell you how well embedded it is. If there's any give however, it should be possible to remove it without much damage to the surrounding concrete, otherwise you could cut it out with a sharp cold chisel...pinenot

 

[NeilPalfreyman]

Thanks for the suggestion - I tried giving it a whack with lump hammer and also tried a cold chisel on it. I don't think it's going anywhere anytime soon!

It's solidly embedded and I suspect that the concrete step will be the first thing to go if I hit it much more.

 

[Harbourwoodwork]

The weather bars are usually only an 1"deep,its probably held at the ends,if you cut it in the middle and prize it up and pull it out in two pieces.That should do the trick