Soil Pipe Vent in the middle of run

[tvrulesme]

Renovating a bungalow which has a detached garage which is ~46cm higher than the main dwelling.

 

Planning a drain run for the two bathrooms. Can I put the vent in the middle of the run as in this picture?

 

Assuming the gradients are correct and the bends are nice and smooth, is there anything else I should worry about from this plan?

 

 

[Nickfromwales]

Yes, that’s fine. Where you show the vent, I assume you realise that will need to be an inspection chamber? 

[tvrulesme]

12 minutes ago, Nickfromwales said:

Yes, that’s fine. Where you show the vent, I assume you realise that will need to be an inspection chamber? 

Where the vent pipe is? I didn't know that, but luckily for me there's a bloody great trench where the vent will be which I dug for other services so should be easy.  

 

Thanks a lot for pointing it out

[Nickfromwales]

If going through building regs, toilet 1 and toilet 2 will need to go to that inspection chamber, and that will go to the ‘manhole’. 
You cannot ‘daisy-chain’ from item to item, as it all needs rodding access at each foul connection eg you need to be able to rod from an IC to each vertically rising SVP ( to a W/C / kitchen sink / ( black or grey waste discharge ) basically anything which takes ‘solids’ or food waste. 
The rule doesn’t always apply where it is just a shower / bath / basin. 
Why are the runs shown in the footprint of the build and not going outside ( around the building ) to the manhole? Access issues? 

[tvrulesme]

2 minutes ago, Nickfromwales said:

If going through building regs, toilet 1 and toilet 2 will need to go to that inspection chamber, and that will go to the ‘manhole’. 
You cannot ‘daisy-chain’ from item to item, as it all needs rodding access at each foul connection eg you need to be able to rod from an IC to each vertically rising SVP ( to a W/C / kitchen sink / ( black or grey waste discharge ) basically anything which takes ‘solids’ or food waste. 
The rule doesn’t always apply where it is just a shower / bath / basin. 
Why are the runs shown in the footprint of the build and not going outside ( around the building ) to the manhole? Access issues? 

Yes the pavement is directly on the other side of the wall. The existing drain also runs directly under the room where Toilet 2 will be so hoping to make a connection to this underground within the room. I understand this will not require an access chamber inside the room if the branch junction is 45 degrees or less.

 

Here's the inside of the manhole. Am I am confusing my manholes with my inspection chambers?

 

 

 

[tvrulesme]

The manhole/inspection chamber in the picture is on my property. Should have said

[Nickfromwales]

The second inspection chamber can be smaller, 300mm iirc. They’re both “inspection chambers” aka “manholes”   

For main junctions they’re 600mm round or the brick rectangular existing ones as in your pic.

Runs from any IC to a black or grey source need to be straight lines, or as near as damnit. BCO’s, usually, will not allow a 45 and much prefer straight line of sight.

They won’t fail existing, so if toilet 2 is existing with the 45 before the manhole that’s fine, but they won’t allow you to add more to that afaic as there would be no access upstream. 
Where you wrote “soil vent pipe”, is that outdoors? Odd space?
If so, can you take toilet 2 existing feed and carry that on in a straight line? Then have the new 300mm IC between the buildings, outside, with toilet 1 feeding into that IC in a straight line. 

[tvrulesme]

30 minutes ago, Nickfromwales said:

The second inspection chamber can be smaller, 300mm iirc. They’re both “inspection chambers” aka “manholes”   

For main junctions they’re 600mm round or the brick rectangular existing ones as in your pic.

Runs from any IC to a black or grey source need to be straight lines, or as near as damnit. BCO’s, usually, will not allow a 45 and much prefer straight line of sight.

They won’t fail existing, so if toilet 2 is existing with the 45 before the manhole that’s fine, but they won’t allow you to add more to that afaic as there would be no access upstream. 
Where you wrote “soil vent pipe”, is that outdoors? Odd space?
If so, can you take toilet 2 existing feed and carry that on in a straight line? Then have the new 300mm IC between the buildings, outside, with toilet 1 feeding into that IC in a straight line. 

It is outside yes. And yes, a very odd space. It’s a very unusual plot. Neither toilet exists at the moment so this would all be new pipework

Edited April 23, 2022 by tvrulesme
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