What height can new door thresholds be in existing flats?

[dodgems2023]

I have a question regarding building regulations and adding new doors to a lower ground floor victorian flat (which was part of a house conversion 70 years ago).

 

I am installing new steps down to a new door and I am considering how low the ground/landing outside the door can be.

 

I have 3 options so far:

 

1)  the external landing outside the new front door to be 15mm lower than the door threshold, and to form part of steps that go up to street level.

This means that water running down the steps would pass over the landing (outside the door) before sloping away to a garden patio 150mm lower (than the landing) where there is a  gulley.

 

2) Same as 1) except the door sill to be 75mm higher than the external landing. 

 

3) the external landing outside the door to be about 220mm lower than the door threshold.

So you have to step up to the door and over the threshold to get inside.

 

Any suggestions much appreciated!

 

Fyi, I have also have an existing side access door which opens up to a staircase inside the flat which I am replacing as they are pretty dangerous!

 

[Temp]

As I recall Part M of the regs (on disabled access) say you shouldn't make things worse for wheelchair users but in your case I don't think any of the options would be significantly worse given the steps down.

 

 

[Dave Jones]

i dont believe part M applies to existing flat conversions/alterations.

[dodgems2023]

Thanks all!

 

No, I don't think the existing flat even currently complies with Part M (1) visitable dwellings

 

You don't enter at the principal storey where there is a WC or other habitable rooms.

 

The existing side (main entrance) door, opens out.

Then to enter the flat you step down onto the first step of a stair case down to habitable rooms.

 

The new additional front door I am proposing will have external steps down to a door.

So you will enter (more or less) at the same storey as habitable rooms.

 

But I just couldn't find anything on how high or low a door threshold can be above the ground immediately outside it!

 

 

[Mr Punter]

Part M is for new dwellings.  As long as you don't make yours worse you are fine.  I would be wary about a drain blockage allowing water into the flat in heavy rain, so a decent threshold would be my choice.  A circa 150mm step up or over the door threshold would be good.