Any way of having shallower drains?

[Markbon]

By my calculations in order to get a 1 in 40 drop I'm going to need to dig down 900mm by the stack. I'm not too keen as that means the drains trench runs along the house foundations at about the same depth.
The only thing I can think of and I've never heard of it but.... Is there a chamber that allows the waste to enter at one level and exit at a lower level without having to rod it after every meal. That way I could put it half way down the line and have shallower drains by the house.

 

[trojanhawrs]

What are you trying to do? The bigger the pipe the less fall required, generally.

 

[Markbon]

What are you trying to do? The bigger the pipe the less fall required, generally.

Everything including toilet. A steep fall would help.

 

[Hugh Jaleak]

The Fall is important, so don't compromise on that. Too shallow and the solids will sit and block the pipe, too steep and the water can race away leaving solids behind, 1:40 on a 4" pipe is rule of thumb, but down to 1:100 is permissible in some applications. Secondly, drains need to be protected from damage for obvious reasons, so if laid at a shallow depth may need some additional protection, i.e. concrete.

Changes in height where the drain needs to drop any distance are usually done by means of a 'Backdrop'. Incoming pipe at the higher level drops, either inside or outside the chamber, (Internal or external). and discharges at the level of the outgoing pipe. A junction is usually fitted (in the correct orientation!) to divert the incoming soil downwards, and allowing a continuation of the horizontal run at the higher level into the chamber for rodding access.

 

[Markbon]

The Fall is important, so don't compromise on that. Too shallow and the solids will sit and block the pipe, too steep and the water can race away leaving solids behind, 1:40 on a 4" pipe is rule of thumb, but down to 1:100 is permissible in some applications. Secondly, drains need to be protected from damage for obvious reasons, so if laid at a shallow depth may need some additional protection, i.e. concrete.

Changes in height where the drain needs to drop any distance are usually done by means of a 'Backdrop'. Incoming pipe at the higher level drops, either inside or outside the chamber, (Internal or external). and discharges at the level of the outgoing pipe. A junction is usually fitted (in the correct orientation!) to divert the incoming soil downwards, and allowing a continuation of the horizontal run at the higher level into the chamber for rodding acce

Like this?

 

[Hugh Jaleak]

Like this?

Exactly like that.

 

[Markbon]

Exactly like that.

That'll do for me. Thanks very much.