Trench and excavation

Bedding, cut, and the OSHA protection that deep trench needs.

Every run carries its depth, so the excavation comes out of the same takeoff as the pipe. Trench settings are per system, and they apply variably along each run by its depth profile - a run that starts shallow and ends deep is calculated as what it actually is, not blanketed at one depth.

Bedding and cut

Setting	What it is
Below Pipe (In.)	Bedding under the pipe.
Above Pipe (In.)	Cover over it.
Side Space (In.)	Clearance each side.
Min Width (Ft.)	Floor on the trench width.
% Pipe Covered	How much of the pipe the stone surrounds.
Exclude Pipe	Take the pipe's own volume out of the stone.
Multiplier (CY-TN)	Converts stone volume to weight.

Deep trench protection

Below a certain depth the walls have to be held. Protect Deeper Than (Ft.) sets where that starts, and Protection Method sets how:

None.
Sloped Sides - the walls lay back at a Slope Ratio (H : 1 V). Presets follow OSHA soil types: Type A is 0.75 : 1, Type B is 1 : 1.
Trench Box - a box of a given Box Height (Ft.) and Box Cut Width (Ft.), with the sides sloping out above the box where the dig is deeper than the box is tall.

In the box method, sloped length is a SUBSET of boxed length. Never add the two together. A run deep enough to need sloping above the box is boxed and sloped over that stretch, and the two figures describe the same feet of trench from different angles.

Depths are true dig depth - the depth you entered plus the bedding below the pipe - so the protection threshold is measured against the hole that actually gets dug rather than against the pipe invert.

Seeing it on the plan

Trench Bounds draws the excavation along each run:

Dashed - the cut edge at grade, flaring out where the sides slope.
Solid - the physical edge: the trench box, or the bottom width.

It is the quick check that a trench is not running into something it should not.