Finished Floor Level Above Dpc

I m currently building a single story extension on my house.

Finished floor level above dpc.

The ground level dpc is actually required to be at least 150mm above the ground level see building regulations for england wales part c section 5 5. The walls are built from concrete blocks and is almost ready for flat roof construction. I am looking to build an outside patio area to the same level as the internal kitchen diner floor. That the dpc is at least 150mm above ground level.

A damp proof course is a barrier usually formed by a membrane built into the walls of a property typically 150 mm above ground level to prevent damp rising through the walls. The floor can be wherever you want it obviously even well below ground level in the case of. Finished floor level same as ground level. This is to reduce the incidence of splashback from rain and to ensure a minimum amount of elevation above standing water that may come about in exceptionally heavy rain or other.

Rising damp and some penetrating damp can be caused by faults to or the absence of a damp proof course dpc or damp proof membrane dpm. If the dpc of the existing building is lower than the finished floor level of the extension timber floor on property and i want a solid floor in the extension will the membrane i put down stop any issue with having the finished floor level above dpc inside. I have measured to the dpc from the current path shown on the image below current sits at just. Unfortunately i have noticed the inner leaf dpc is a whole block above finished floor level.