Remove existing threshold for new french doors?

22 Jul 2022
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United Kingdom

I've been on this website many times - thanks for all your helpful responses to posts !! Posting myself for the first time...

I'm replacing a sliding patio door with french doors - I've got an existing 5cm threshold and I'm getting mixed advice about removing it or not.
- If I remove it, the (3cm) cill will start 5cm below internal flooring height. The frame-threshold is 7cm but 2cm will now be hidden sitting above the sill.
- If I keep it, the cill will just sit on top of the existing one and stick upwards 3cm above internal flooring height!

Any advice?


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Note: I'm just a diy'er.

If it were me, I'd investigate getting the existing (wooden?) cill removed so the 30mm upvc cill sits at that level, reducing the amount of the 70mm threshold that's exposed internally. The lip if you like.

Can the supplier/manufacturer not offer some advice?
My concern would be that the uprights are morticed in to the sill.

Can't you just remove the required amount from the sill? Admittedly a bit of an awkward jog with the sill in situ.
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Have you bought this French door already?

If not, could you not have it made-up with either a low threshold cill or deeper one, depending on what you decide?

My brother wanted low threshold door but bought a cill version. We removed a course of brick and built up to the required level, so the floor covering runs flush to the door cill.
Thanks for the responses. So,
- I asked one manufacturer and they said to get a "professional installer" to review it. If I remove the cill, 70cm will be hidden as you mentioned but then won't look symmetrical with the top
- @ opps, I think this is one realistic option but I do have a multitool and a sander to potentially make this work
- @ Mr Chibs, it's looking like this is going to be the option to go for - and what I tried to avoid by posting here as it's more work & time :)

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