Lowering basement floors - underpinning

Structure · Problems · printed page 37 (PDF page 38)

Book index entries

Basement – Floors Lowering with Underpinning Lowered Basement Floors – Underpinning Underpinning Footings – and Foundations Foundation – and Footing

Text in the illustration

wall framing
floor framing
topsoil
foundation wall
backfill
original footing
original drainage tile
original floor level
new concrete underpinning (footing extension)
new concrete floor slab
gravel
new interior drainage tile sometimes installed
cross section

Generated explanation

The cross section illustrates lowering a basement floor by extending the foundation support downward with concrete underpinning beneath the original footing. The existing foundation wall supports wood wall and floor framing, with topsoil and backfill on the exterior side. A dashed outline marks the original floor level above the new concrete floor slab. The lowered slab rests on gravel beside the underpinning, with an optional new interior drainage tile shown below its edge. The original exterior drainage tile remains beside the original footing.

Components

wall framing floor framing foundation wall original footing concrete underpinning concrete floor slab exterior drainage tile interior drainage tile gravel base backfill

Materials

wood concrete masonry blocks gravel soil

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