Excavation depth reaches undisturbed soil, not fill
Why — act while you have leverage
A footing built on loose filled-in earth or topsoil settles unevenly, and the crack that follows shows up in the walls a year later — long after the contractor has been paid.
What to look at
- Soil colour and texture changing to a firm consistent stratum
- No roots, rubbish or earlier construction debris in the base
- Depth measured from a fixed reference, not from the current ground level
How to check it yourself
Excavation continues until it reaches firm original ground that has never been dug or filled — never stopping at the level the drawing assumed. Have the depth checked against the structural drawing before any levelling course goes in, and photograph the open pit with a tape in frame.
Where this comes from: IS 1904:1986 (foundations in soils, general requirements); NBC 2016 Part 6 Section 2 (indian standard or building code)
More excavation and setting-out checks
- Photograph before this is covered
- Setting out checked against the plot boundary and setback
- Anti-termite treatment applied before the levelling course