Running drainage pipe under concrete slab

[flanagaj]

I need to route a rain water drainage pipe under the concrete slab.  As you can see from the image there is only about 150mm clearance from the top of the pipe to the underside of the concrete slab (red line)  Part H indicates that I need to encase the whole pipe in concrete, but I didn’t find it very clear and wondered if anyone can provide any further guidance on how I should do this.  I also wonder whether I should change the pipe for socketed?

 

 

[BotusBuild]

I have to concrete part of my rainwater drainage as well. Been told it doesn't have to be a strong mix. Must be capable of holding the pipe in place and stopping surrounding ground movement (or wall movement ib your case I guess)

 

I'd remove the pipe bedding you have and prop up with offcuts of blocks then pour concrete. No need to change the pipework.

[flanagaj]

3 hours ago, BotusBuild said:

I have to concrete part of my rainwater drainage as well. Been told it doesn't have to be a strong mix. Must be capable of holding the pipe in place and stopping surrounding ground movement (or wall movement ib your case I guess)

 

I'd remove the pipe bedding you have and prop up with offcuts of blocks then pour concrete. No need to change the pipework.

Ok, thanks.  Do you surround the whole pipe in concrete?

[BotusBuild]

Yes. You can put some polystyrene round to protect it a bit if you want.

 

I remember digging a foundation by hand years ago, and coming across the storm water drain, then the foul drain below it. Both were encased in concrete. I had surround these with polystyrene, then reinforcing rods before the foundations for an extension were built. I was a teenager at the time, and my reward was a new stereo 😀

 

You'd think I would have learnt my lesson before building a whole house nearly 50 years later

[Oz07]

I think i'd be digging out the pea gravel, bedding and surrounding these in lean mix concrete. Possibly a 25mm bit of eps where the pipe joint is to allow some movement. You don't really want the ground at the edge of you slab settling.

[Oz07]

blockwork looks much better this time!