Python SL

Python SL is a fast setting, protein free, cement based self-levelling compound used to level out rough and uneven floors and screeds in preparation for laying floor coverings. Python SL can be applied to a depth of 12mm in one application when simply mixed with water or to a maximum depth of 25mm when mixed with 3 – 5mm aggregate. Python SL is fast setting and it will accept light foot traffic after 4 hours and after 8 hours ceramic, porcelain and natural stone tiles can be applied. Soft flooring such as linoleum and vinyl can be applied after 48 hours. Python SL is only suitable for use over solid substrates such as sand/cement screed and concrete.

• Sand/Cement Screed
• Concrete
• Plywood Overlay (12mm min)
• Chipboard Overlay (18mm min)
• Electric Underfloor Heating
• Water/Wet System Underfloor Heating
• Tile Backer Boards
• Existing Ceramic, Porcelain and Natural Stone Tiles
• Flooring Grade Asphalt & Bitumen
• Anhydrite Screeds
• Fibre Cement Sheet
• T & G Floorboards
• Floating Floors
• Existing Vinyl Tiles
• Steel/Metal Surfaces
• Existing Adhesive Residues
• Green Screed
• Fibreglass

Before starting, all substrates must be clean, dry and strong enough to support the weight of the Python SL, adhesive and the final floor covering being applied. Remove all dust, dirt, oil, grease and other contaminants that may affect adhesion. Where traces of adhesive remain, these must be strong, sound and well adhered to the substrate.

The substrate must be confirmed dry by consistent moisture readings; <75% relative humidity (RH) or <0.5% residual moisture content prior to application. Remove any loose or flaking layers. Laitance should be removed from concrete and sand/cement screed surfaces. Sub-floors directly to earth must have a damp-proof membrane.

Mix by adding Python SL to clean water, approximately 4.2 – 4.8 litres of water to 20kg of Python SL. We suggest starting with 4.2 litres of water which can then be increased to a maximum of 4.8 litres if necessary. Python SL will flow better at 4.8 litres of water, however, do not exceed 4.8 litres of water per bag of Python SL. Exceeding 4.8 litres of water per 20kg will result in water bleed and therefore extended drying times and a weakened mix.

Mix ideally with an electric paddle until you obtain a smooth and lump free consistency. When mixed allow to stand for 2 minutes and stir again before application. Once mixed, Python SL will remain workable in the bucket for approximately 30 minutes.

Pour a small quantity onto the prepared surface and trowel down lightly to a depth between 2 - 12mm. The use of a spiked roller is recommended in order to remove entrapped air and smooth out flow lines. Python SL will maintain a “wet edge” for 20 – 30 minutes but depending on the porosity of the substrate and ambient conditions, once applied, the drying process can begin after 15 – 20 minutes.

For depths greater than 12mm, aggregate should be added to Python SL for increased economy and performance. Add 3 – 5mm aggregate at a rate of 2 parts Python SL to 1 part aggregate. Add powder to water and use the water additions stated on the product packaging, please note that the water additions may vary slightly depending on the aggregate used. Pour a small quantity onto the prepared surface and trowel down lightly to a maximum depth of 25mm. If you wish to apply a second coat of Python SL, allow the first coat to dry and prime between applications.

Python SL must be left to dry before applying the final decorative surface flooring. This is typically 8 hours for ceramic, porcelain and natural stone tiles and 48 hours for soft flooring such as linoleum and vinyl. The setting time will depend on atmospheric conditions/temperatures, it will be slowed by lower temperatures and accelerated by higher temperatures.

N.B. If there is no air flow within site conditions, the drying time may be restricted.

The critical moisture content for the flooring in question must be observed. If in doubt, please call our technical department on

020 8778 9000.