Conservatory base as patio?

[dormermike]

Hi all

Currently got a 10m wide conservatory and looking to get rid. Turns out the floor is insulated and the stud walls are 800mm foundations, and it was all laid at the same time as the main part of the house extension which was done in the 90s. We've had an architect draw up plans to use half the footprint of the conservatory as a new room. The remaining half will have the dwarf walls and floor finish removed, and turned into patio onto which the existing lounge will open onto via double sliding doors.

My concern and I mentioned this to the architect is that the new patio, aka old conservatory floor, has a DPM which is joined to the lounge DPM. He has suggested an acro (?) Drain across the double doors on the patio side for drainage, and he said concrete is waterproof so the dpm will not transfer water inside.

Am I right or is he right? I am reluctant to pull up the Connie floor completely just to relay it as patio, but am concerned in case the dpm causes issues.

Thanks

 

[Ivor Windybottom]

Aco drain.

You're right to be concerned. The DPM in the new room should be a contiguous barrier that laps up into the walls. He should know this, if he doesn't then find someone who does.

You can use the old base as patio, the issue is that the new room's floor must be completely separated from the outside. Concrete is definitely not waterproof.