The minimum distance between finished ground level and DPC is 150mm.
This is a statutory building regulation as well as an NHBC standard.
NHBC standards 6.1 S4 states:
"At ground level, all parts of the dpc should be at least 150mm above finished ground or paving level."
You should refuse to let them install ACO channels until your complaint has been reviewed by the NHBC.
As for Taylor Wimpey Regional directors you should e mail michelle.grant@taylorwimpey.com
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