Planning guide
What is topsoil?
Topsoil is the upper, biologically active soil layer used to establish lawns, improve grades, and fill planting areas. Purchased blends vary in sand, silt, clay, and organic content.
How this calculation works
Volume equals surface area multiplied by finished depth. Because soil settles, the displayed 10% allowance is especially useful for fill and grading work.
Common measurement mistakes
- Assuming every topsoil blend weighs the same
- Ignoring settlement after watering
- Adding a thick incompatible layer over poorly drained clay
Professional tips
- Choose screened soil for lawns and finish grading
- Loosen the existing surface before spreading
- Match the blend to drainage and planting needs
Topsoil Calculator FAQs
How much extra topsoil should I buy?
A 10% allowance is a practical starting point for settling, spillage, uneven grade, and measurement error. Complex shapes may justify a little more.
Should I measure before or after edging?
Measure the finished inside dimensions of the area. Permanent edging occupies space and should not be included in the material footprint.
What depth should I use?
Lawn repairs often use 1–2 inches (2.5–5 cm); new beds commonly use 4–8 inches (10–20 cm) depending on existing soil.