Basement for existing structure

[netix]

We need to install a water proof basement under an existing buildings wall, probably using structural steel frame:

natural clay becoming firmer with depth at 7 ft from ground level

Objective is to avoid having to shore up the walls, if possible.

Has any one experience of the following method

1. placing a pillar outside and at each end of a wall
2. inserting girder connecting pillars
3. internal support pillars where necessary
4. do this for all walls to create supporting structural load baring frame

Are there alternatives?

Jon
Netix4@yahoo.com

 

[idl]

Jon:
What is the physical size of the existing building? Is it a single/double storey? What was it is made of?

 

[netix]

This is a tradional brick building with slate roof:
ground approx 1,800 sq ft and two other stories above

total including ground is approx 3,000 sq ft.