Hi,
When measuring the location of drain pipes and the actual size of the slab , would contractors use the edge piers as the boundary of the slab?
Basically my engineering gives the options of putting in bored piers or screw piles. So my builder uses screw piles. The diameter of a screw pile is significantly less than a bored pier (450mm)..
And the piles are drilled into positions marked with "+" sign on the ground. The plus sign is like 450mm diameter.
So if they use the top of the screw pile as guide basically the measurements would be all wrong. From the drain pipes to the slab.
I rather not ask my builder for now, trying not to barge into their area of expertise and get the look of "Leave the building to us"...
They haven't don't the slab form work yet.
I'm sure all is well and they know what they are doing.. I'm just been a little paranoid.
The location of the piers don't determine the extents of the slab, a surveyor does (using the structural drawings and the site plan).
Any piers located along the perimeter of the slab are likely to be centred on the perimeter/edge ribs (likely annotated as PR or ER on your structural drawings). If the pier diameter is greater than the width of the edge rib, then a portion of each pier will project beyond the face of the slab in the vertical plane.
The location of the piers don't determine the extents of the slab, a surveyor does (using the structural drawings and the site plan).
Any piers located along the perimeter of the slab are likely to be centred on the perimeter/edge ribs (likely annotated as PR or ER on your structural drawings). If the pier diameter is greater than the width of the edge rib, then a portion of each pier will project beyond the face of the slab in the vertical plane.
Thanks. I gather that much. Just need assurance.
After the site was cut and then pegged the detailed pegging and lines were lost during the installation of piers and the drainage.
Except for the further out pegs not on the perimeter of the slab foot print.
Then they re flatten and compact the areas that will be the footprint of the slab.
I guess those outer peggings will be used during the form work of the slab? But they don't look very detailed compare to the initial pegs.
Why don't you wait until they've installed the edge boards and then measure it to satisfy yourself?
There's no harm in keeping an eye on things, but there's also no point speculating before the fact - you'll just drive yourself crazy. In the event that they set it out incorrectly, it's easy to rectify before the pour.