Back fill for under slab drain line

Help Support Plumbing Forums:

PrecisionPlum

Active Member
Joined
Jul 9, 2017
Messages
37
Reaction score
1
Location
,
Code calls for no rocks around a drain line. Typically there is 4" of 3/4 crushed stone under a 4" residential basement
slab. As a drain line runs under a slab it passes through the stone and up through the concrete, but passing through
the stone seems to be in conflict with the plumbing code. What is the typical construction and plumbing practice.
 

breplum

Professional
Professional
Joined
Nov 14, 2017
Messages
526
Reaction score
173
Location
Lafayette, CA
The point of "no rocks" is to prevent damage to the pipes.
Drainage rock found typically under slabs have edges that are not good.
The best practice under the pipe is to use "base rock" which is "road base" grade of crushed rock, which has enough fine/crushed material so that it can be thumped down smooth and hard under the pipe to prevent sags (assuming you disturbed the soil underneath).
Wrap to protect pipe penetrations thru concrete (of course), or if drain rocks will come in contact.
 

Latest posts

Top