Backfilling trench with flinty soil

[flanagaj]

The excavated soil from the foul drainage trench is very flinty and I wanted to ask whether I could backfill the trench using said soil if I cover the foul drainage with 100mm of pea shingle or should I get someone in to screen it first.   Trying to avoid unnecessary expenditure, but also possible problems in the future.

 

 

[BotusBuild]

If you're putting pea shingle in first, backfilled with the excavated spoil. No need to screen it 

[Nickfromwales]

7 hours ago, flanagaj said:

The excavated soil from the foul drainage trench is very flinty and I wanted to ask whether I could backfill the trench using said soil if I cover the foul drainage with 100mm of pea shingle or should I get someone in to screen it first.   Trying to avoid unnecessary expenditure, but also possible problems in the future.

 

 

Have you haunched with a sand & cement mix, to set the pipes in situ? 
 

After that you should have 100mm of pea shingle under and 100mm over, and only pick out any obvious foreign objects.

[flanagaj]

36 minutes ago, Nickfromwales said:

Have you haunched with a sand & cement mix, to set the pipes in situ? 
 

After that you should have 100mm of pea shingle under and 100mm over, and only pick out any obvious foreign objects.

Rest bends haunched.  Pea shingle layers done as described.  Picking out obvious foreign objects impossible.

[Nickfromwales]

3 hours ago, flanagaj said:

Rest bends haunched.  Pea shingle layers done as described.  Picking out obvious foreign objects impossible.

Mid sections of pipe runs not haunched? To prevent deflection.

 

Foreign objects like a 1/3 of a patio slab or a house brick, visible when migrating the spoil and back-filling.