คำนวณปริมาตรคอนกรีต ขนาดลูกตั้งลูกนอน และความหนาพื้นบันได ภาพจำลอง 3D และราคาวัสดุ
Use this calculator for a straight concrete stair flight. It estimates the stair shape and concrete volume, but it does not replace local code checks or structural design.
The tool estimates a straight stair as step triangles plus the sloped waist slab. Landings, beams, side walls, reinforcement, formwork, and waste are not included.
Try a 2800 mm rise, 175 mm target rise, 250 mm tread, 1000 mm width, and 150 mm waist thickness to estimate a compact residential-style flight.
Increase the tread depth and save the calculation. The concrete volume and floor run will grow, but the stair may feel less steep.
Change only the stair width to see how volume and cost scale for a wider flight.
Use finished floor levels when you know them. Floor finishes can change the real rise and make the first or last step uneven.
The warnings are quick checks only. Stair rules differ by country, building type, and local authority.
The estimate is for the straight flight only. Add landings, edge beams, waste, and delivery minimums outside this tool.
Waist thickness affects volume and structure. Use the value from your drawing or ask an engineer for structural work.
Save a few rise and run options so you can compare comfort, footprint, concrete volume, and cost.
A steep angle can save space but may be uncomfortable or fail local rules. Adjust rise and run before pricing material.
Concrete estimates are based on clean dimensions. Real pours often need extra for uneven ground, form losses, and ordering rules.