Sewer pipe going through footings

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Hi all just after a little advice.

In the process of adding a single storey single skin extension to our existing outhouse, with wall total 8m x3m x 2.6m

Ok so starting to have the founds dugout (going for Strip Foundations), and found a sewer pipe going diagonally across the trench for the footings, now its about a 150mm pipe (by looking down the man hole), but it has previously probably by the council, been encased in thick concreate to around 500mm+ .

So my question is will this have to be bridged over in some shape or form (concrete lintel), or as the depth is going to be thinker than the footings, can I just build over it with aggregate blocks as its already encased in think concreate?

All Advice is appreciated :)
 
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In our area under council engineer advice, we put 75mm of bubble wrap around the pipes, then 200 mm of loose chicken wire, then pour concrete.
Bubble wrap can be removed once concrete is set, leaving the pipe bridged and free to move if required.
This of course if iyhe pipe is deep enough to be within the concrete, otherwise just bridge it with concrete lintels.
 
In our area under council engineer advice, we put 75mm of bubble wrap around the pipes, then 200 mm of loose chicken wire, then pour concrete.
Bubble wrap can be removed once concrete is set, leaving the pipe bridged and free to move if required.
This of course if iyhe pipe is deep enough to be within the concrete, otherwise just bridge it with concrete lintels.

Yep the lintel was an idea but wondering if i need to, as the 150mm pipe is already encased in around 350mm thick of concreate, so would that not be strong enough for a 2.6m high single skin wall?
 
150mm Id guess thats a public sewer.

Sadly that means a build over agreement, which may require a CCTV inspection.

The foundations will need to be 150mm deeper than invert level.
 
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Yep the lintel was an idea but wondering if i need to, as the 150mm pipe is already encased in around 350mm thick of concreate, so would that not be strong enough for a 2.6m high single skin wall?
What's supporting the 350mm concrete around the pipe?
 
What's supporting the 350mm concrete around the pipe?

Not sure to be honest as its already encased, most likely since the property was built way back, going to dig down a little further to see if its also sitting on a found or just on the soil, I will update tomorrow when I dig down.

Thanks to everyone so far for your comments
 
It needs to be bridged, not just encased. Foundations need to be lower than the pipe. Above all, you need to determine if the pipe is the responsibility of the water company or you.
 
It needs to be bridged, not just encased. Foundations need to be lower than the pipe. Above all, you need to determine if the pipe is the responsibility of the water company or you.

In some cases fundations cannot be lower than pipe.
Pipes cannot be always bridged, hence the solution above.
 
If pipes are a metre down and depth of fundations specified at 1.5m, you won't be able to bridge the pipe with a lintel, but you'll be forced to use the "hole in footing" method explained above.
 
If pipes are a metre down and depth of fundations specified at 1.5m, you won't be able to bridge the pipe with a lintel, but you'll be forced to use the "hole in footing" method explained above.

Ok so hole in footing, do you mean the "75mm of bubble wrap around the pipes" option ?
 
If pipes are a metre down and depth of fundations specified at 1.5m, you won't be able to bridge the pipe with a lintel, but you'll be forced to use the "hole in footing" method explained above.
That makes no sense.

The pipes are higher than the bottom of the foundation, so of course they can be bridged.
 
How do you know?
Have you been on the site?
And in any case, it doesn't work as you imagine.
 
Any pipe can be bridged whether that be by using shuttering or by keeping the top of the concrete below the pipe and bridging it with masonry. It does however become very tricky if the pipe crosses the trench over a long distance and acute angle.

I'd be more inclined to try to re-route the pipe in this instance.

We had one that crossed the trench (short distance) 1.6m down. We formed a box shutter and placed it over the pipe, then concreted over it.
 

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