Estimating · 10 June 2026
The Set-Down That Moves Your Price 8%
Set-downs are subtle on a plan and brutal on a margin. Why they're measured in lineal metres, why estimators miss them, and how they move a price 8% or more.
What is a set-down in a concrete slab?
A set-down is a deliberate step or drop in the top level of a concrete slab. They are typically engineered in wet areas (such as bathrooms and laundries) or external balconies to allow space for screed, waterproofing, and tiles so that the finished floor sits flush with the rest of the building.
How do you price a set-down?
A set-down creates a vertical face within the slab. This vertical face requires formwork on both sides, propping, and stripping. Therefore, set-downs must be measured and priced in lineal metres along the perimeter of the step, not as part of the general square-metre area of the slab.
Why do estimators miss set-downs?
Set-downs are one of the most frequently missed items in a formwork takeoff because they are visually subtle on architectural plans. The architectural floor plan often reads as a clean, flat plate. The drop is usually only called out on the structural engineering sheets, sometimes just as a single note or a lightly hatched zone.
If an estimator only quotes off the architectural set, they quote a flat slab. On a large residential project, missing 40 lineal metres of set-downs means missing days of labour, which can easily move the true cost of the formwork by 8% or more.