Floor levelling plaster LT 4000

Base 

• Concrete substrates
• The substrate must be clean, solid, and dust-free, and it must be vacuumed.
• Loose layers, cement laitance, and other impurities must be mechanically removed to ensure proper adhesion between the floor screed and the substrate.
• The substrate must be sufficiently strong, stable, and load-bearing.
• The tensile strength of the substrate must be > 1.0 MPa.
• The temperature of the subfloor structure must be > +10°C and the relative humidity < 95% RH. The subfloor’s relative humidity affects the drying time of the floor screed.
• If necessary, uneven areas should be pre-filled with Fescon LM 5000 before applying the floor screed.

Priming 

• Priming is carried out according to the instructions for Fescon Adhesion promoter or Flow Primer, depending on the substrate.
• Non-absorbent surfaces (e.g. ceramic tiles, epoxy, metal surfaces) must be pre-treated in accordance with the Primer PLUS instructions.

Instructions for use 

• The working area must be fully protected from wind, drafts, sunlight, and rain.
• During floor installation, the indoor temperature must be between +10°C and +25°C, and the relative humidity must be above 40% RH.
• One 20 kg bag of screed is mixed with 3.6–4.0 litres of cold water.
• Overdosing water is prohibited, as it weakens the strength properties of the screed, increases the risk of separation, and prolongs the drying time.
• The screed must be mixed into a homogeneous mass using a power drill with a mixing paddle.
• Apply the screed to the substrate and level it with a steel trowel.
• Working time is approx. 0.5 hours from the addition of water.
• Clean tools immediately after use with water.
• Hardened screed must be removed mechanically.

Flooring 

• Floor levelling plaster LT 4000 can be directly waterproofed using certified products from the Fescon Waterproofing system.
• It can be covered with ceramic tiles, plastic coverings, textile carpets, vinyl tiles, engineered wood/laminate flooring, and cork. If necessary, a skim coat with Fescon hand-applied levelling compounds, such as FlowPlan, should be used.
• It must be ensured that the screed meets the technical requirements of the floor covering manufacturer and the RYL guidelines for the substrate, taking the entire structure into account. The flatness of the screed surface should be measured, if necessary, in accordance with RT instruction 14-11039.
• The floor screed must not be left uncoated for more than 3 months due to the risk of cracking and detachment.
• Once the screed has reached the required moisture level for the selected floor covering, the floor must be covered or post-treatment initiated.
• Check the moisture content of the entire floor structure before installing the floor covering.
• Good drying conditions for the screed require that the indoor relative humidity is below 50% RH and the temperature is above +20°C. Poor conditions will slow down the development of the screed’s strength properties and extend the drying time.

Storage and handling of waste
See the separate storage and disposal instructions https://www.fescon.fi/en/material-bank