Basement

[i_am_fubar]

The house I'm in is a solid slab foundation with short brick walls supporintg the joists of the downstairs floor.

The (or rather, 'a') DPC is built into those short walls. Would I therefore be right in assuming the slab foundation doesn't/shouldn't/won't have a DPM under it?

That question then leads onto this one.

What is the legal and structural ramifications of digging through that slab and making a small cellar/basement underneath? I appreciate that it will require structural work to reinforce the undercut.

This room would not be for occupation and would be accessable via a ladder and only used for storage (or, if needed, in the event of a zombie invasion). Probable dimenstions 2m high + length of connecting hole. 4m x 4m area. Considering hollow dence concrete blocks filled with concrete to make up walls and appropriate moisure barrier with a concrete floor.

Sam.

 

[freddiemercurystwin]

You would certainly need Building Regs Approval, the cost of tanked retaining walls and everything else that such works entail for new cellars may be cost prohibitive but that bits down to you! Structurally it will depend on the existing foundations, their proximity to the new cellar, water table level and ground conditions. There are several ways to achieve a watertight retaining wall such as this, reinforced concrete, mass blockwork walls, blocks filled with concrete etc and just as many different types of tanking methods. When you approach SE's you need to make sure they'll provide a method statement for the builder to follow (or instructions) ie dig out and build 1m segments at a time or whatever. The existing slab may or may not have a dpm but unlikely. Have a read here: http://www.planningportal.gov.uk/permission/commonprojects/basements/

 

[^woody^]

You would also need planning permission as this is not permitted development.

The Party Wall Act may also apply

You slab would not normally have a DPM