Expansion Joint Movement Calculator

Enter your structure’s span, material and temperature range — we’ll compute the thermal movement your joint must accommodate and recommend the right Dseal system, instantly.

1Your structure

Slide the values to match your project.

Span between joints 30 m

Structure material

Min temperature 5 °C

Max temperature 55 °C

Joint location

Floor

Wall / Façade

Roof

Seismic

Traffic (floor)

Pedestrian

Light

Medium

Heavy

Extra seismic / structural movement 0 mm

2Required movement

Total design movement (thermal × 1.3 design factor + any seismic allowance).

Design movement

0mm

total design movement the joint must accommodate

0 mm150 mm300 mm+

Material—

Temperature swing (ΔT)—

Thermal movement (α·L·ΔT)—

Design factor× 1.3

Seismic / structural—

Required design movement—

3Recommended Dseal systems

Matched to your movement, location and traffic. Sizes are indicative — our engineers confirm the final selection.

How this is calculated ▾

Thermal movement is calculated as Δ = α × L × ΔT, where α is the material’s coefficient of thermal expansion (e.g. reinforced concrete ≈ 12×10⁻⁶/°C, aluminium ≈ 23×10⁻⁶/°C), L is the span between joints, and ΔT is the temperature swing the structure experiences (max − min surface temperature). A 1.3 design factor is applied to cover installation tolerance and construction movement, and any seismic/structural movement you enter is added. The required figure is the total movement range the joint must absorb over its life.

This tool provides an indicative first estimate for early design and product selection only. Actual movement depends on structural design, exposure, restraint, installation temperature and applicable codes. Always confirm the final joint selection with a qualified engineer — our technical team will validate the specification for your project. Request a reviewed recommendation →