Marking location of soil pipes through slab

[gavztheouch]

About to start my foundation. Is it worth running string lines with batter boards to mark out the location of things like soil pipes and ducts bring electric in etc. is this over kill? It would be a lot more work than just marking the four corners of the foundation. What method is best?

 

I could just measure off the external perimeter with a tape to get x and y coordinates.

 

 Feel like I’m overthinking this one. I’m using an insulated slab.

[nod]

Overkill 

[markc]

Keep It Simple ! 

[Alan Ambrose]

@nod - what’s the usual method of getting these in the right place? I could see that even a few inches out might be tricky in some circumstances.

[Duncan62]

I have this problem coming up. Never done it before.

 

I'm thinking that I will need a X and Y measurement but also both diagonals, say  A and B from each front corner - to check that it's actually square.

 

Measure twice and maybe three times.

[Russell griffiths]

Get your architect to put them on the drawings with centres marked from external walls. 
mark out walls, or get your surveyor to do it, best idea. 
when walls are narked measure from these and bang a steel pin in location of pipe. 

[saveasteading]

You are right to be thinking ahead. What is the issue? Do the pipes go through the concrete footing? If so, I would put an oversize boxing to allow for adjustment later. If above the footings, the question is for the next stage.

[gavztheouch]

Hi all dimensions and details of installation are know ie insulation around the pipe to allow for movement. It’s more a question of how you would normally measure the position is a tape measure form the string line of the external walls ok

[saveasteading]

56 minutes ago, gavztheouch said:

is a tape measure form the string line of the external walls

Yes. But note that concreting is a gutsy job and marks will disappear and pipes get moved. 

You're just thinking a long way ahead I assume. So think ahead to pipes through the walls. I like a small lintel and a generous hole , which is infilled later.

[Temp]

Design out the need for precise location.