VELOSIT SL 501

Cementitious self-levelling underlayment for prepared concrete and subsequent floor coverings. Technical details are attributed to the archived VELOSIT source 3619. 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

25 kg watertight plastic bagvelosit sl 501 tds; 3619 pp. 4

Thickness

3–38 mmvelosit sl 501 tds; 3619 pp. 1

Water addition in source

17–18%; stated as 4.2–4.5 L per 25 kgvelosit sl 501 tds; 3619 pp. 2

Working time

30–40 minutes at 23 °Cvelosit sl 501 tds; 3619 pp. 3

Coverage

Approximately 11 kg/m² at 6 mm on a smooth substratevelosit sl 501 tds; 3619 pp. 3

Volume yield

Approximately 14 L cured mortar per 25 kgvelosit sl 501 tds; 3619 pp. 3

Substrate temperature

10–35 °Cvelosit sl 501 tds; 3619 pp. 3

Compressive strength in source tests

12 MPa at four hours; 34 MPa at 28 daysvelosit sl 501 tds; 3619 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 1.0/20 MPa with specification-dependent exceptions. Select primer from measured moisture conditions: PA911 is described for the stated low-moisture conditions; higher or increasing moisture requires the different specified system. Wood or steel are conditional specialist substrates. Rake or pump onto the correctly primed substrate within the stated thickness. Do not overwater or cover untreated cracks and joints. The source says no curing treatment is required but still requires 24-hour protection from direct sun, wind and temperature changes greater than 5 °C. Confirm covering readiness for the actual conditions and floor finish.

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 promote this underlayment as an unqualified finished industrial wear surface.
• Do not use storage temperature as application temperature.
• Do not omit joints, substrate-moisture requirements or 24-hour protection.

• Primer selection and moisture criteria, 10-35 °C application temperature, and initial protection must follow the complete system sheet. Storage temperature is a separate limit.

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