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Kelmore LevelMore Flex & Fibre is a high-performance, fibre-reinforced smoothing compound designed for demanding subfloors. Its protein-free, rapid-setting formula is engineered for both interior and exterior use, offering exceptional strength and flexibility.

Key Features

• Suitable for Interior and Exterior use
• Can be installed as a durable wearing surface
• Moisture tolerant – can be used below damp proof membranes
• Outstanding workability and flow
• Sets with a smooth, consistent surface finish
• Protein-free formulation with high dimensional stability

Technical Information

• Classification (EN 13813) - CT-C25-F7
• Pack Size - 20kg
• Water required per 20kg bag - 4.5-5.0 litres
• Application Temperature (air and background) - ≥ 5˚C
• Application Thickness - 2-50mm (75mm when bulked out)
• @20˚C Working time - 30 minutes
• @20˚C Walk on - 90 minutes
• @20˚C Tile after - 2 hours
• @20˚C Fit resilient floor coverings after - 3 hours
• Consumption per mm thickness - Approximately 1.55kg /m2

Area Of Use

• Floors
• Interior and Exterior
• Domestic and Commercial
• Below Damp Proof Membranes
• Water Piped and Electric Underfloor Heating
• Limited Movement / Vibration

Background and Surface Preparation

Backgrounds must be sufficiently dry and strong enough to carry the total weight being applied. All surfaces must be clean, sound and free from contaminants that could impair adhesion, such as dust, dirt, oil, grease, laitance, and curing agents. Timber bases must be rigid, stable and adequately ventilated. They should support both static and dynamic loads without deflection and be covered with an appropriate intermediate layer.

PRIMER REQUIRED
FOR THE FOLLOWING - PrimeMore Universal

• Cement: Sand Screed - (Inc. Heated)
• Concrete
• Plywood Overlay (Class 3)
• Tile Backer Boards

Prime with one coat of PrimeMore Universal diluted 1:3 with water. Depending on the porosity of the background, additional coats may be required. The primer must be allowed to dry before applying LevelMore Flex & Fibre

PRIMER REQUIRED
FOR THE FOLLOWING - PrimeMore Grip

• Asphalt - (Flooring Grade)
• Epoxy DPM
• Existing Ceramic, Porcelain, and Natural Stone Tiles
• Metal (Steel)

Prime with one neat, undiluted coat of PrimeMore Grip. The primer must be allowed to dry before applying LevelMore Flex & Fibre

PRIMER REQUIRED 
FOR THE FOLLOWING - PrimeMore CS

• Calcium Sulphate/Anhydrite Screed (Inc. Heated)

Prime with one neat, undiluted coat of PrimeMore CS. The primer must be allowed to dry before applying LevelMore Flex & Fibre

Guidance notes on suitable floor backgrounds

CEMENT:SAND SCREED
Tile-Fixing (Porcelain & Ceramic):

• Allow new screeds to dry for at least 3 weeks.
• Direct fixing of agglomerate and some natural stone tiles will require extended drying times.
• For proprietary screeds, follow the manufacturer’s recommendations for preparation and drying times.

Fitting Resilient Floor Coverings:

• Ensure the screed has an effective structural damp proof membrane and is dry (≤75% RH).
• If a structural damp proof membrane is absent or ineffective, apply One Coat DPM Fast or One Coat DPM Trade to the surface.
• PrimeMore MVS may be used where residual construction moisture is present up to 95% RH, whilst One Coat DPM Fast and One Coat DPM Trade are suitable for use up to 98% RH.

HEATED CEMENT:SAND SCREED

New screeds must be commissioned from 3 weeks after screed installation and before work commences.

• Heat slowly at a maximum rate of 5°C per day until the maximum operating temperature is reached.
• Hold this temperature for 3 days before allowing the screed to cool to room temperature.
• For proprietary screeds, follow the manufacturer’s recommendations for commissioning and preparation.

Fitting Resilient Floor Coverings:

• After commissioning, continue to run the underfloor heating until the screed is confirmed dry (≤75% RH).
• PrimeMore MVS may be used on prepared and commissioned heated screeds where residual construction moisture is present up to 85% RH. Alternatively, One Coat DPM Fast and One Coat DPM Trade may also be used on prepared and
  commissioned heated screeds. The underfloor heating should be switched off 48 hours prior to commencing work.

CONCRETE
Tile-Fixing (Porcelain, Ceramic, & Natural Stone):

• Allow new concrete to cure before being subjected to continuous air drying in good conditions for at least 6 weeks.
• Power floated concrete should be mechanically prepared to achieve a clean, sound, micro-textured, dust-free surface.

Fitting Resilient Floor Coverings:

• Ensure all concrete, including power floated concrete, has an effective structural damp proof membrane and is dry (≤75% RH).
• If a structural damp proof membrane is absent or ineffective, apply One Coat DPM Fast or One Coat DPM Trade to the surface.
• PrimeMore MVS may be used where residual construction moisture is present up to 95% RH, whilst One Coat DPM Fast and One Coat DPM Trade are suitable for use up to 98% RH.
• Power floated concrete must also be mechanically prepared to achieve a clean, sound, micro-textured, dust-free surface.

PLYWOOD OVERLAY (CLASS 3)
Fitting Resilient Floor Coverings:

• Plywood must be a minimum 6mm thick and conditioned to the appropriate moisture content for the environment.
• Fix using screw nails, ring shank nails, or screws every 100mm at the sheet’s perimeter and 150mm elsewhere.

TILE BACKER BOARDS

• Must be installed as instructed by the manufacturer and be securely fixed to rigid, suitable, prepared bases.
• Where boards have been installed on solid bases using tile adhesive, ensure the adhesive has fully set before commencing work.
• Please note that some proprietary board manufacturers may specify a minimum compound thickness when installing certain floor coverings to prevent point-loading issues.
  

Prime the following backgrounds with one neat, undiluted coat of PrimeMore Grip. Allow the primer to dry before applying the flooring compound.

FLOORING GRADE ASPHALT

• Must be hard, sound and firmly adhered.

EPOXY DPM

• Must be a flooring grade that is compatible with cementitious products.
• Ensure it is hard, sound and firmly adhered.

EXISTING CERAMIC, PORCELAIN, AND NATURAL STONE TILES

• Must be in good condition, free from contaminants and well bonded.
• Ensure the existing structure can take the additional weight.

Fitting Resilient Floor Coverings:

• If the existing tiles are fixed to a subfloor that does not contain an effective structural damp proof membrane, Kelmore DPM must be applied to the surface of the prepared tiles.

METAL (STEEL)

• Must be rigid, corrosion-free and clean.

Prime calcium sulphate/anhydrite screeds with one neat, undiluted coat of PrimeMore CS. Allow the primer to dry before applying the flooring compound.

CALCIUM SULPHATE/ANHYDRITE SCREED

• All laitance and surface contaminants must be completely removed.

Tile-Fixing (Porcelain, Ceramic, & Natural Stone):

• The screed must be confirmed adequately dry (≤85% RH).

Fitting Resilient Floor Coverings:

• The screed must be confirmed dry (≤75% RH).

HEATED CALCIUM SULPHATE/ANHYDRITE SCREED

• All laitance and surface contaminants must be completely removed.
• New heated screeds must be commissioned from 7 days after screed installation and before work commences.
• The screed should be heated slowly and in accordance with the recommendations of the screed manufacturer.

Tile-Fixing (Porcelain, Ceramic, & Natural Stone):

• The screed must be confirmed adequately dry (≤85% RH).
• Switch off underfloor heating 48 hours prior to commencing work.

Fitting Floor Coverings:

• After commissioning, continue to run the underfloor heating until the screed is confirmed dry (≤75% RH).
• Switch off underfloor heating 48 hours prior to commencing work.

ADDITIONAL INFORMATION

Moisture Tolerance: LevelMore Flex&Fibre is suitable for use on damp subfloors, provided no surface water is present. It can also be used below damp proof membranes, and when used to pre-smooth textured subfloors, it enhances the coverage of Kelmore DPM.

Underfloor Heating: LevelMore Flex&Fibre can be used to encapsulate electric underfloor heating cables which have been adhered to prepared floors. For resilient floor coverings, it should be applied at the thickness recommended by the manufacturer to ensure the floor covering does not suffer heat damage

After completing installations on backgrounds incorporating underfloor heating, the heating system should not be run for 10 days. Following this period, the floor temperature must be gradually raised to its optimal operating temperature, with an increase of no more than 2ºC per day.

Impervious Backgrounds: To provide an absorbent base for the application of adhesives, when fitting resilient floor coverings, LevelMore Flex&Fibre must be applied at a minimum thickness of 3mm.

Timber Floors: LevelMore Flex&Fibre can be used to smooth or level uneven timber floors prior to overlaying with plywood or tile backer boards. The timber floor must be rigid, adequately ventilated and free of all contaminants that could impair adhesion and be primed with PrimeMore Grip. Allow the primer to dry before applying the compound, and the compound must be allowed at least 3 hours to fully dry before fitting the sheets or boards.

Multiple Layers: Where possible, LevelMore Flex&Fibre should be applied at the desired thickness in a single application. If required, additional layers - which must not exceed the thickness of the previous layer - may be applied once the compound is walkable and primed with diluted PrimeMore Universal.

Wearing Coat: When used as a wearing coat in domestic environments, LevelMore Flex&Fibre must be applied at a minimum thickness of 6mm. For use as a wearing coat in commercial environments, please contact Kelmore's technical department for advice.

External Use: Whilst still allowing the product to air cure, protect from rainfall and frost for at least 24 hours.

Protein-Free: LevelMore Flex&Fibre is suitable for use in biologically sensitive areas.

Mixing

Add 4.5-5.0 litres of clean, cold water to a clean mixing bucket. Gradually add one 20kg bag of LevelMore Flex&Fibre, and mix thoroughly using a paddle mixer until a smooth, lump-free consistency is achieved. The compound is ready for use immediately after mixing.

Bulking Out

Where depths from 50-75mm are required in a single application, LevelMore Flex&Fibre can be bulked out with sharp sand or 1-3mm granite chippings at a 2:1 ratio by weight (2 parts Flex&Fibre to 1 part aggregate). After mixing 20kg of Flex&Fibre with 4.75 litres of clean, cold water, add 10kg of aggregate and remix until fully incorporated.

Application

Pour the mixed compound onto the prepared floor, then use a trowel, rake or pin leveller to regulate the thickness and guide the product into the desired areas. If the applied thickness allows, a spiked roller may be used within the working time to remove any trapped air and further enhance the surface finish.

Pumped Application

Mix according to the pump manufacturer's recommendations ensuring the correct water ratio is maintained. The mixed product should be smooth and fluid and have no surface separation or bleed. Flow checks should be performed regularly during the pumping process.

Drying

Drying times will vary dependent on the porosity of the background, ambient temperature and humidity. When tested to the industry standard temperature of 20°C, LevelMore Flex&Fibre can be walked on after 90 minutes. Resilient floor coverings can be fitted after 3 hours, and porcelain, ceramic, and natural stone tiles can be fixed after 2 hours. Please note that higher temperatures and low humidity will accelerate the drying, whilst lower temperatures and high humidity will delay it.

Notes:

• Cementitious products should only be used when both air and background temperatures are 5ºC or higher. If the temperature falls below 5ºC, the chemical reaction required for the product to set is hindered, dramatically slowing the curing process. Normal setting will only resume once temperatures rise. However, if temperatures drop below freezing before the product has fully set, the integrity and performance of the product will be compromised.

Cleaning: All tools should be cleaned with water after use and before the product sets.

Health and Safety: For full details, please refer to the Safety Data Sheet, available at www.kelmore.co.uk or by contacting Kelmore Ltd.

Storage and Shelf Life: When stored in unopened packaging, off the ground, and in cool, dry conditions, this product
has a shelf life of 12 months.