VELOSIT SL 503

High-strength cementitious self-levelling overlayment for specified concrete-floor applications. Technical details are attributed to the archived VELOSIT source 2619. Confirm the current matching manufacturer documentation and project suitability before use.

Reviewed technical data

Recorded source values with stated conditions. This review does not establish a current product release or approval.

Packaging

20 kg watertight plastic bagvelosit sl 503 tds; 2619 pp. 4

Thickness

3–38 mmvelosit sl 503 tds; 2619 pp. 1, 2

Water addition

4.2–4.4 L per 20 kgvelosit sl 503 tds; 2619 pp. 2

Working time

30–40 minutes at 23 °Cvelosit sl 503 tds; 2619 pp. 2

Coverage

Approximately 10.5 kg/m² at 6 mm on a smooth substratevelosit sl 503 tds; 2619 pp. 3

Volume yield

Approximately 11.4 L cured mortar per 20 kgvelosit sl 503 tds; 2619 pp. 3

Substrate temperature

10–35 °Cvelosit sl 503 tds; 2619 pp. 3

Compressive strength in source tests

20 MPa at four hours; 65 MPa at 28 daysvelosit sl 503 tds; 2619 pp. 3

Storage

The archived sheet states 12 months in unopened original packaging at 5–35 °C, dry and protected from sunlight. Confirm the supplied batch and current manufacturer requirements.

Method of application

Prepare sound, rough, open-pore concrete. The source gives minimum adhesive/compressive substrate strengths of 2.0/30 MPa with specification-dependent exceptions. Repair active leaks and cracks and select primer using the specified substrate-moisture criteria. Rake or pump onto the correctly primed substrate within the stated thickness; do not overwater or coat untreated joints and cracks. For use as a wear surface the source recommends a clear sealer, surface hardener or FH921 to improve resistance to penetrating liquids. Protect for 24 hours from direct sun, wind and temperature changes greater than 5 °C.

Safety notes

Consult the current product safety data sheet and follow its handling measures before use. The archived technical sheet is not a substitute for an SDS.

For project selection and substrate-specific advice, contact technical support.

• Do not substitute the 25 kg basis of SL501/SL502.
• Do not omit joints, substrate-moisture requirements or 24-hour protection.
• A wear surface may require the specified sealer or hardener; FH921 is one listed option, not the only permitted finish.

• Retain the 20 kg pack basis, 10-35 °C application temperature and initial protection. Confirm the selected compatible finish.

Confirm the exact supplied product, substrate, exposure and current TDS/SDS with technical support.