finishing damp proof membrane around a door

[DanDIY]

I have knocked through several rooms downstairs. Some of the floors were at different levels, so I dug it out and have put a new floor in. The floor was sand, damp proof membrane, 100mm celotex and 100mm of screed.

When the floor went in the doors weren't in, but the doorways were knocked out. I've got some little gaps to fill in where I blocked the doorways up with 4x2 wood. I was planning on mixing up some 4:1 sharp sand/cement to fill these.

All this seems quite straightforward but when the screed dried out I cut the damp roof membrane flush with the edge of my floor. Now I need to fill in the doorways the membrane wont stretch round the little recesses.

I was considering either:

1. just fill the gaps in. The gaps are on top of the blue brick course anyway.

2. join some extra membrane to cover the gaps - one of the reasons I am not so sure about this is that it will mean that the side of the membrane is up against my wooden doorframe, so if any damp did come up from underneath it might rot my door.

or is there a third way....?

Here are some pictures.

 

[ree]

I find it hard to understand your posted details. Without a section view of what you now have its difficult to advise.

I'm guessing but just filling the gaps with a semi-dry 3:1 mix should be OK.

I assume the "100mm of screed" means 100mm of concrete? Screeds go above the concrete.

Basically, you should leave the membrane flapping high up any abutment, and only cut it when your finished floor is in - it sometimes goes up behind the skirting before being cut.

I dont see any edge insulation.

 

[DanDIY]

Hi. Thanks for replying.

There is no edge insulation in this bit because I cut it back to get a smooth joint between the floor that is already there and the patch that I am going to have to add. There is insulation around the rest of the floor.
The floor is concrete, with some polymer fibers in it.

here is a section plan

underneath the membrane it is sand to stop the membrane getting pierced, which is on top of klinker/broken bricks with earth underneath. Although the property didn't have a damp 'problem' before, the klinker bed was certainly damp. What I want to understand is will any moisture wick up the sides of the membrane, and if this is going to happen can I stop it?....or am I worrying over nothing?!

 

[ree]

Thank you for the section view: I've suggested the answer above.