--- title: Liquid Nails SLC50 Leveller - Self-Levelling canonical_url: https://directory.selleys.com.au/flooring/flooring-products/liquid-nails-slc50-leveller-self-levelling/ category: description: geography: city: state: country: metadata: phone: email: website: publishedAt: productInfo: stock: True productFeedItemId: 6575d885-ee38-4755-9f0b-270f34516e8b --- # Liquid Nails SLC50 Leveller - Self-Levelling ## AI Summary **Product:** Selleys Liquid Nails SLC50 Leveller **Brand:** Selleys **Category:** Self-smoothing cementitious floor levelling underlayment **Primary Use:** Prepares concrete substrates by creating a flat surface before timber flooring, carpet, or ceramic tile installation. ### Quick facts - **Best for:** Flooring contractors, building professionals, and experienced DIYers preparing concrete slabs for timber flooring systems - **Key benefit:** Self-smoothing formula flows under gravity to achieve a level surface without skilled troweling, handling feather edge to 50mm depth in a single pour - **Form factor:** Grey powder supplied in 20kg paper bags - **Application method:** Mix with clean water using a paddle mixer, pour onto prepared concrete substrate, and distribute with a gauge rake ### Common questions this guide answers 1. How much water do I mix with SLC50? → 4.4 litres per 20kg bag for standard self-levelling (up to 10mm); 4.0 litres per 20kg bag for ramping mix (up to 50mm) 2. When can I walk on SLC50 after application? → Approximately 3–4 hours at 20°C; full strength develops over approximately 28 days 3. Is SLC50 hazardous to use? → Yes — contains respirable crystalline silica classified as a Category 1A carcinogen (H350); mandatory PPE includes a P2/N95 respirator, chemical splash goggles, and impermeable gloves --- ## Product overview and positioning Selleys Liquid Nails SLC50 Leveller is a self-smoothing cementitious levelling underlayment built specifically for preparing concrete substrates before timber flooring installation (TDS). With 80+ years of brand heritage, this compound does one thing exceptionally well: it turns uneven, damaged, or substandard concrete slabs into the flat surfaces that modern timber flooring actually needs. SLC50 sits within a specific niche of floor preparation materials. It forms part of the Selleys Liquid Nails Timber Flooring System, designed to work alongside the manufacturer's moisture barriers and flooring adhesives (TDS). The formulation prioritises adhesion to concrete, self-levelling behaviour, and cure times that keep projects moving on schedule (TDS). The cement-based chemistry delivers a smooth, hard surface ready for timber, carpet, and ceramic tile (TDS). This is a product that rewards technical understanding of substrate preparation, mixing, and application. It suits experienced DIYers, flooring contractors, and building professionals who need consistent, predictable results across interior and exterior environments (TDS). ## Chemistry and composition Liquid Nails SLC50 is a cementitious mortar built on portland cement chemistry (TDS). The formulation contains 30–60% portland cement by weight, along with aggregates and modifiers that govern flow, adhesion, and cure behaviour (SDS). That cement concentration provides the compressive strength needed for load-bearing floor applications. The formulation also contains crystalline silica below 1% by weight, including respirable crystalline silica fractions above 0.1% (SDS). This matters during mixing and application: respirable silica particles become airborne easily and present a serious inhalation hazard. The crystalline silica content places SLC50 in the Category 1A carcinogen classification (SDS), which means dust control and respiratory protection aren't optional. When mixed with water at the specified ratios, the portland cement hydrates and transforms the powder into a flowing slurry, then progressively into a rigid cementitious matrix. The self-smoothing behaviour comes from calibrated particle size distributions and flow modifiers that let the mixed compound find its own level under gravity, removing the need for extensive troweling (TDS). The grey colour of the cured product reflects the natural pigmentation of portland cement and the aggregate system (TDS). No significant VOCs are present, making SLC50 suitable for occupied buildings and environments with air quality restrictions (TDS). ## Technical specifications breakdown ### Packaging and coverage SLC50 comes in 20kg paper bags (TDS). Each bag covers approximately 12 square metres at 1mm thickness, or 4 square metres at 3mm thickness (TDS). These figures assume proper substrate preparation, correct water ratios, and uniform application. At the maximum recommended thickness of 50mm in a single pour, coverage drops to roughly 0.24 square metres per bag. ### Mix ratios and consistency control SLC50 has two mixing protocols, each suited to a different application (TDS): **Standard self-levelling mix:** One 20kg bag with 4.4 litres of clean water produces a free-flowing consistency for thin-section levelling up to approximately 10mm (TDS). This ratio prioritises flowability, letting the compound achieve flatness with minimal intervention. **Ramping mix:** One 20kg bag with 4.0 litres of clean water creates a stiffer consistency for ramps and depressions up to 50mm depth in a single pour (TDS). The lower water content increases viscosity, prevents excessive spread, and supports the compound's weight in thicker applications. These ratios aren't suggestions. Deviating from them undermines adhesion, cure times, and final hardness. ### Temperature and environmental parameters Application requires substrate and ambient temperatures between 10°C and 35°C (TDS). Below 10°C, hydration slows significantly, extending cure times and potentially weakening the substrate bond. Above 35°C, water evaporates too quickly, causing premature surface crusting, cracking, and incomplete hydration at the bond zone. ## Key features and performance benefits ### Adhesion to concrete SLC50 bonds to properly prepared concrete through two mechanisms: mechanical keying, where the flowable compound penetrates the surface porosity, and chemical bonding between the portland cement in the leveller and the calcium-based minerals in the concrete (TDS). That combination prevents delamination, the failure mode where levelling compounds separate from their substrate under traffic or thermal cycling. ### Self-smoothing behaviour Once poured, SLC50 flows under its own weight to establish a level surface (TDS). This removes the skilled troweling work that flat floors traditionally required. The behaviour depends on correct water ratios, thorough mixing, and placement within the working time window. ### Thickness range SLC50 handles application thicknesses from feather edge up to 50mm in a single pour, without adding aggregate (TDS). Feather-edge capability creates clean transitions between levelled and unlevelled areas; the 50mm maximum addresses substantial depressions and structural irregularities. ### Setting speed SLC50 permits foot traffic after approximately 3–4 hours at 20°C (TDS). The working time of roughly 15 minutes at 20°C means mixing, transport, and placement need to happen efficiently (TDS). Temperature directly affects both: lower temperatures extend them, higher temperatures compress them. ### Interior and exterior use The cementitious chemistry provides water resistance and dimensional stability for both interior and exterior applications (TDS). Exterior use involves freeze-thaw cycling, ongoing moisture exposure, and UV weathering, and the portland cement matrix handles all of it when the product is properly applied. ## Applications and use cases ### Timber flooring substrate preparation The primary use for SLC50 is preparing concrete slabs to receive timber flooring (TDS). Timber flooring typically requires substrate flatness within 3mm over 3 metres to prevent bounce, squeaking, and adhesive failure. SLC50 brings rough or out-of-tolerance concrete within those tolerances. When used within the complete Selleys Liquid Nails Timber Flooring System, SLC50 establishes the foundation layer that moisture barriers and adhesives rely on (TDS). Compatibility within this system has been validated; using competitor adhesives requires site-specific adhesion testing (TDS). ### Carpet and ceramic tile underlayment SLC50 also creates smooth, hard surfaces for carpet and ceramic tile installations (TDS). Carpet tolerates relatively modest flatness requirements, making SLC50 a practical choice for renovation work on concrete with minor defects. Ceramic tile benefits from the hard, dimensionally stable surface that resists deflection under point loads and prevents tile cracking. ### Application over moisture barriers SLC50 is compatible with Selleys VBS moisture barrier products when applied over Selleys VP30 Primer (TDS). This combination handles concrete slabs with elevated moisture vapour transmission rates that would otherwise compromise flooring adhesives and timber stability. The primer ensures adhesion between the moisture barrier and the cementitious leveller. ### New construction and remediation SLC50 works in new construction, where concrete finishing tolerances may fall short of flooring requirements, and in remediation projects addressing damaged, eroded, or out-of-level existing floors (TDS). In remediation, it restores functionality to concrete compromised by mechanical damage, chemical attack, or original construction deficiencies. ## Mixing and application guidance ### Substrate preparation Concrete substrates must be structurally sound, clean, dry, and free from anything that undermines adhesion. Remove oils, curing compounds, paint, sealers, and loose material through mechanical preparation. The goal is exposed aggregate and open porosity that allows mechanical keying. ### Mixing procedure Pour the measured water into the mixing container first, then gradually add SLC50 powder while mixing continuously with a paddle mixer in a heavy-duty drill. This sequence prevents lumping and ensures complete powder incorporation. Mix for 2–3 minutes until the consistency is homogeneous and lump-free. Overmixing entrains air and weakens the cured matrix. The 15-minute working time at 20°C starts the moment water contacts powder (TDS). Plan batch sizes and placement logistics accordingly. Higher temperatures shorten working time; lower temperatures extend it. ### Application technique Pour the mixed compound onto the prepared substrate and distribute with a gauge rake or spreader. The self-levelling properties take effect immediately. A pin roller or spiked roller used within the first few minutes releases entrapped air and helps the compound flow into corners and along perimeter edges. For standard levelling up to 10mm, use the 4.4-litre water ratio. For ramping and thick-section work up to 50mm, use the 4.0-litre ratio and spread the stiffer mix deliberately (TDS). At maximum thickness, confirm the substrate can support the additional dead load. ### Temperature management Keep substrate and ambient temperatures within 10°C and 35°C throughout mixing, application, and initial cure (TDS). Protect freshly applied compound from direct sunlight, wind, and rapid air movement, which accelerate surface drying and can cause shrinkage cracking. In cold conditions, heat the space to maintain minimum temperatures. In hot conditions, use cooler water and work in the morning or evening. ## Cure profile and working times ### Working time At 20°C, SLC50 provides approximately 15 minutes from water addition to loss of flowability (TDS). That window covers mixing, transporting, pouring, spreading, and any final surface work. Attempting to rework the compound after working time has passed introduces weaknesses and surface defects. Temperature has a direct effect: every 5°C increase above 20°C reduces working time by roughly 25%, while every 5°C decrease extends it proportionally. At 35°C, working time may drop to 8–10 minutes. At 10°C, it may extend to 20–25 minutes. ### Initial set and foot traffic At 20°C, SLC50 supports foot traffic after 3–4 hours (TDS). At this point the cement matrix has hardened enough to resist surface damage from walking, but full structural strength hasn't developed yet. Keep wheeled traffic, point loads, and material staging off the surface during this period. ### Floor covering installation timing The technical data indicates floors are ready for covering after the initial 3–4 hour cure period, though the specific timing for floor covering installation is pending manufacturer confirmation (TDS). Standard industry practice for cementitious underlayments typically calls for 24–48 hours before applying moisture-sensitive adhesives, and 7–28 days for full design strength, depending on temperature, humidity, and application thickness. ### Full strength development Portland cement products continue hydrating for weeks after application, with most strength development occurring in the first 28 days. SLC50 accepts light traffic and floor covering installation well before that point, but maximum hardness and structural capacity build over the full period. ## Hazards and PPE requirements ### Carcinogenicity and respiratory hazards Liquid Nails SLC50 is classified as Category 1A carcinogenic because of its respirable crystalline silica content (SDS). The H350 hazard statement "May cause cancer" reflects the International Agency for Research on Cancer's Group 1 classification of crystalline silica as a human carcinogen (SDS). Chronic inhalation of respirable silica causes silicosis, a progressive and irreversible lung disease, and raises lung cancer risk. The H335 hazard statement "May cause respiratory irritation" covers acute effects from dust inhalation during mixing and application (SDS). Fine alkaline particles irritate respiratory tract mucous membranes, causing coughing, throat discomfort, and breathing difficulty. These hazards require genuine dust control: mix in well-ventilated areas or outdoors (P271), avoid breathing dust during bag opening and powder addition (P261), and use respiratory protection when ventilation is insufficient (SDS). ### Skin and eye hazards SLC50 causes skin irritation (H315) through the alkaline pH of portland cement (SDS). Contact produces redness, drying, and cracking; prolonged contact can cause chemical burns. The more serious concern is Category 1 eye damage (H318): contact with the powder or wet mix can cause permanent vision impairment or blindness through corneal destruction (SDS). P280 requires protective gloves, protective clothing, and eye/face protection during all handling (SDS). Following eye contact, P305+P351+P338 specifies rinsing cautiously with water for several minutes while removing contact lenses if present (SDS). P310 requires immediately calling a poison centre or doctor after eye exposure (SDS). ### Personal protective equipment Mandatory PPE for SLC50 handling: **Respiratory protection:** A P2/N95 dust respirator minimum when mixing or handling dry powder in inadequately ventilated spaces. The respirable silica content justifies respiratory protection even when visible dust appears minimal. **Eye protection:** Chemical splash goggles or a face shield with complete eye coverage. Standard safety glasses with side shields are not sufficient against splashing during mixing or accidental bag rupture. **Skin protection:** Impermeable gloves (nitrile, PVC, or rubber) extending to mid-forearm, plus long-sleeved protective clothing. Contaminated clothing must be removed and washed before reuse (P362+P364) (SDS). **Foot protection:** Waterproof boots to prevent the wet alkaline mix from contacting skin through conventional work boots. ### First aid response **Skin contact** (P302+P352): Wash with soap and water for at least 15 minutes (SDS). If irritation develops, seek medical advice (P332+P313) (SDS). **Eye contact** (P305+P351+P338): Rinse cautiously with water for several minutes. Remove contact lenses if present and easy to do (SDS). Continue rinsing and immediately call a poison centre or doctor (P310) (SDS). **Inhalation** (P304+P340): Move the person to fresh air and keep them comfortable for breathing (SDS). Seek medical attention if respiratory symptoms develop or persist. **Medical information:** Have the product container or label available when seeking medical advice (P101) (SDS). ## Storage and handling ### Storage requirements Store SLC50 in a well-ventilated location with containers kept tightly closed (P403+P233) (SDS). The paper bag packaging is moisture-permeable: humidity or liquid water causes premature hydration and makes the product unusable. Store in a dry environment, elevated off concrete floors, protected from rain and condensation. P405 requires storing locked up (SDS), addressing both security and the product's corrosive and carcinogenic properties. Keep out of reach of children (P102) (SDS). Temperature extremes don't chemically degrade unhydrated powder, but freeze-thaw cycling after moisture exposure can affect performance. Storage between 5°C and 30°C maintains quality. ### Shelf life and quality assurance The manufacturer has not specified a shelf life for SLC50. Portland cement products generally maintain full performance for 6–12 months when stored correctly. Beyond that, cement hydration activity gradually declines, potentially extending cure times and reducing final strength. Don't use bags showing moisture damage, lumping, or hardening. ### Disposal requirements P501 requires disposing of contents and container per local, state, national, and international regulations (SDS). Hardened waste is generally non-hazardous and can be disposed of as construction and demolition waste in most jurisdictions. Wet or unhardened material needs solidification before disposal. Check with local waste authorities regarding the crystalline silica content. SLC50 is not classified as Dangerous Goods under the Australian Code for Transport of Dangerous Goods by Road & Rail or New Zealand NZS5433 (SDS), which simplifies transportation and storage from a regulatory standpoint, though the health hazards remain unchanged. ## Expert tips and best practices ### Substrate moisture testing Before applying SLC50 or any moisture barrier system, test concrete moisture vapour transmission rates using calcium chloride testing or in-situ relative humidity probes. Elevated moisture causes flooring adhesive failure and timber instability. Identifying moisture issues before levelling allows for more thorough remediation. ### Primer selection for non-standard substrates When applying SLC50 over moisture barriers, the VP30 Primer specification ensures proper adhesion (TDS). For applications over questionable concrete or previously sealed surfaces, test the primer on representative areas before committing to full-scale application. ### Batch consistency On large projects requiring multiple 20kg bags, use calibrated measuring containers rather than estimating water volumes. Variations in water content produce visible differences in flow, self-levelling behaviour, and surface finish between batches. ### Environmental control during cure Protect freshly applied compound from rapid moisture loss during the first 24 hours. In hot, dry, or windy conditions, light misting after initial set can prevent shrinkage cracking. Avoid saturating the surface, which weakens the developing matrix. ### Floor flatness verification After cure, check flatness with a 2–3 metre straightedge and feeler gauges. Confirm compliance with flooring manufacturer specifications before proceeding with floor covering installation. Finding flatness problems after installing timber flooring is an expensive situation to be in. ### Compatibility testing with non-system products SLC50 is optimised for the Liquid Nails Timber Flooring System, but use with competitor adhesives requires site-specific adhesion testing (TDS). Apply test sections, allow full cure, then assess the flooring system. Inadequate adhesion shows as clean debonding at the leveller-adhesive interface. ### Working time management in temperature extremes At temperatures approaching 35°C, pre-cool mixing water to extend working time. At temperatures near 10°C, pre-warm mixing water (not above 30°C) to accelerate initial hydration. ### Crystalline silica exposure Beyond PPE requirements, use source control: open bags slowly, mix outdoors or in ventilated areas, clean up with wet methods rather than dry sweeping, and dispose of packaging promptly. Cumulative exposure over years of professional use is the primary carcinogenic risk. ## References - Source PDF: SELLEYS_LIQUID_NAILS_SLC50-AUS_GHS.pdf (canonical) - Source PDF: [selleys-liquid-nails-slc50-tds.pdf](selleys-liquid-nails-slc50-tds.pdf) (secondary) ## Frequently asked questions What is Selleys Liquid Nails SLC50: A self-smoothing cementitious floor levelling underlayment What is SLC50 primarily designed for: Preparing concrete substrates before timber flooring installation Is SLC50 suitable for carpet underlayment: Yes Is SLC50 suitable for ceramic tile underlayment: Yes Can SLC50 be used outdoors: Yes, it is suitable for exterior applications What is the primary chemical component of SLC50: Portland cement (30–60% by weight) Does SLC50 contain crystalline silica: Yes What percentage of crystalline silica does SLC50 contain: Below 1% by weight Is crystalline silica in SLC50 classified as a carcinogen: Yes, Category 1A carcinogen What is the carcinogen hazard statement for SLC50: H350 — May cause cancer Does SLC50 contain significant VOCs: No, it is a low-VOC product What colour is cured SLC50: Grey What size bag does SLC50 come in: 20kg paper bags What is the coverage of one 20kg bag at 1mm thickness: Approximately 12 square metres What is the coverage of one 20kg bag at 3mm thickness: Approximately 4 square metres What is the maximum application thickness per pour: 50mm What is the minimum application thickness: Feather edge How much water is used for the standard self-levelling mix: 4.4 litres per 20kg bag How much water is used for the ramping mix: 4.0 litres per 20kg bag What is the standard self-levelling mix used for: Thin-section levelling up to approximately 10mm What is the ramping mix used for: Ramps and depressions up to 50mm depth Can water ratios be altered without affecting performance: No, specified ratios are non-negotiable What is the minimum application temperature: 10°C What is the maximum application temperature: 35°C What happens if SLC50 is applied below 10°C: Hydration slows, extending cure times and undermining strength What happens if SLC50 is applied above 35°C: Premature surface crusting, cracking, and incomplete hydration occur What is the working time at 20°C: Approximately 15 minutes Does temperature affect working time: Yes, higher temperatures shorten it What is the approximate working time at 35°C: 8–10 minutes What is the approximate working time at 10°C: 20–25 minutes When can foot traffic resume after application at 20°C: After approximately 3–4 hours How long does full strength development take: Approximately 28 days Does SLC50 self-level without troweling: Yes, it flows under its own weight What mixing tool is required for SLC50: A paddle mixer mounted in a heavy-duty drill How long should SLC50 be mixed: 2–3 minutes until lump-free Should powder or water be added to the container first: Water is added first, then powder What happens if SLC50 is overmixed: Excessive air entrapment weakens the cured matrix What substrate preparation is required before applying SLC50: Remove oils, sealers, paint, and loose material mechanically Does SLC50 bond chemically to concrete: Yes, via portland cement and calcium-based mineral bonding Does SLC50 bond mechanically to concrete: Yes, by penetrating surface porosity What failure mode does strong adhesion prevent: Delamination Can SLC50 be applied over moisture barriers: Yes, when used with Selleys VP30 Primer Which primer is required when applying SLC50 over moisture barriers: Selleys VP30 Primer Is SLC50 compatible with competitor adhesives without testing: No, site-specific adhesion testing is required What system does SLC50 belong to: Selleys Liquid Nails Timber Flooring System What flatness tolerance does timber flooring typically require: Within 3mm over 3 metres Is SLC50 classified as Dangerous Goods for transport: No Is SLC50 classified as Dangerous Goods under Australian road and rail regulations: No What respiratory hazard statement applies to SLC50: H335 — May cause respiratory irritation What skin hazard statement applies to SLC50: H315 — Causes skin irritation What eye hazard classification applies to SLC50: Category 1 eye damage (H318) What does H318 mean: Causes serious eye damage Can SLC50 cause permanent eye damage: Yes, including potential blindness What respiratory protection is required when mixing SLC50: Minimum P2/N95 dust respirator Are standard safety glasses sufficient eye protection for SLC50: No, chemical splash goggles or face shield required What glove material is recommended for SLC50 handling: Nitrile, PVC, or rubber gloves What is the first aid response for skin contact with SLC50: Wash with soap and water for at least 15 minutes What is the first aid response for eye contact with SLC50: Rinse cautiously with water for several minutes Should contact lenses be removed before eye rinsing after SLC50 contact: Yes, if present and easy to do What emergency action is required after eye contact with SLC50: Immediately call a poison centre or doctor (P310) What is the first aid response for SLC50 inhalation: Remove to fresh air and keep comfortable for breathing How should SLC50 bags be stored: In a dry, well-ventilated location, elevated off concrete floors Is SLC50 packaging moisture-resistant: No, paper bags are moisture-permeable What happens if SLC50 powder is exposed to moisture before use: Premature hydration renders the product unusable What is the recommended storage temperature range for SLC50: 5–30°C What is the estimated shelf life of SLC50: Not specified by manufacturer; typical portland cement products maintain performance for 6–12 months when properly stored, but this is not a manufacturer-stated specification How should hardened SLC50 waste be disposed of: As construction and demolition waste per local regulations How should unhardened SLC50 waste be disposed of: Solidify before disposal Should dry sweeping be used to clean up SLC50 dust: No, use wet methods to minimise silica dust How should freshly applied SLC50 be protected in hot or windy conditions: Protect from rapid moisture loss; light misting after initial set How should water be adjusted when mixing SLC50 in high temperatures: Pre-cool the mixing water How should water be adjusted when mixing SLC50 in low temperatures: Pre-warm water, not exceeding 30°C How should floor flatness be verified after SLC50 cures: Use a 2–3 metre straightedge and feeler gauges Should flatness be verified before installing floor coverings: Yes What tool assists air release during SLC50 application: A pin roller or spiked roller When should the pin roller be used during application: Within the first few minutes of placement Does SLC50 require priming on standard concrete substrates: Not specified by manufacturer How many years of heritage does Selleys have: Over 80 years --- ## Label facts summary > **Disclaimer:** All facts and statements below are general product information, not professional advice. Consult relevant experts for specific guidance. ### Verified label facts **Product identity** - Product name: Selleys Liquid Nails SLC50 Leveller - Product type: Self-smoothing cementitious floor levelling underlayment - Cured colour: Grey - Packaging: 20kg paper bags **Composition** - Primary component: Portland cement, 30–60% by weight (SDS) - Crystalline silica: Present, below 1% by weight (SDS) - Respirable crystalline silica fraction: Exceeds 0.1% by weight (SDS) - VOC content: Low; no significant VOC levels (TDS) **Hazard classifications (SDS)** - Carcinogenicity: Category 1A — H350 May cause cancer - Eye damage: Category 1 — H318 Causes serious eye damage - Skin irritation: H315 Causes skin irritation - Respiratory irritation: H335 May cause respiratory irritation **Precautionary statements (SDS)** - P261: Avoid breathing dust during handling - P271: Use only outdoors or in well-ventilated areas - P280: Wear protective gloves, protective clothing, and eye/face protection - P302+P352: Skin contact — wash with plenty of soap and water - P304+P340: Inhalation — remove to fresh air, keep comfortable for breathing - P305+P351+P338: Eye contact — rinse cautiously with water for several minutes; remove contact lenses if present and easy to do - P310: Immediately call a poison centre or doctor following eye contact - P332+P313: If skin irritation occurs, seek medical advice - P362+P364: Remove and wash contaminated clothing before reuse - P403+P233: Store in well-ventilated place; keep container tightly closed - P405: Store locked up - P101: Have product container or label available when seeking medical advice - P102: Keep out of reach of children - P501: Dispose of contents and container per applicable regulations **Coverage (per 20kg bag)** - At 1mm thickness: approximately 12 square metres (TDS) - At 3mm thickness: approximately 4 square metres (TDS) **Application thickness** - Minimum: Feather edge (TDS) - Maximum single pour: 50mm (TDS) **Mix ratios** - Standard self-levelling mix: 4.4 litres of clean water per 20kg bag; for thin-section levelling up to approximately 10mm (TDS) - Ramping mix: 4.0 litres of clean water per 20kg bag; for ramps and depressions up to 50mm depth (TDS) - Sequence: Add water to container first, then gradually add powder (TDS) - Mixing duration: 2–3 minutes until homogeneous and lump-free (TDS) - Mixing tool: Paddle mixer mounted in a heavy-duty drill (TDS) **Temperature parameters** - Minimum application temperature: 10°C (TDS) - Maximum application temperature: 35°C (TDS) - Recommended storage temperature range: 5–30°C **Working time and cure (at 20°C)** - Working time: Approximately 15 minutes (TDS) - Approximate working time at 35°C: 8–10 minutes - Approximate working time at 10°C: 20–25 minutes - Foot traffic: After approximately 3–4 hours (TDS) - Full strength development: Approximately 28 days **Compatible system products** - Moisture barrier primer: Selleys VP30 Primer required when applying over moisture barriers (TDS) - System: Selleys Liquid Nails Timber Flooring System (TDS) **Transport classification** - Not classified as Dangerous Goods under the Australian Code for Transport of Dangerous Goods by Road & Rail or New Zealand NZS5433 (SDS) **Storage requirements** - Store in dry, well-ventilated location, elevated off concrete floors, protected from moisture - Paper bag packaging is moisture-permeable; moisture exposure causes premature hydration - Shelf life: Not specified by manufacturer **Disposal** - Hardened waste: Dispose as construction and demolition waste per local regulations - Unhardened waste: Solidify before disposal - Cleanup method: Use wet methods; avoid dry sweeping to minimise airborne silica dust --- ### General product claims - SLC50 delivers "exceptional adhesion" to concrete substrates - Self-smoothing properties eliminate the need for skilled troweling - Described as suitable for experienced DIYers, flooring contractors, and building professionals - Positioned as part of a validated floor preparation system when used with Selleys moisture barriers and adhesives - Described as suitable for interior and exterior environments - Described as suitable for transforming uneven or damaged concrete into flat surfaces - Claimed to prevent delamination under traffic loads and thermal cycling - Described as providing inherent water resistance and dimensional stability for exterior use - Selleys brand heritage stated as 80+ years - Flatness tolerance guidance for timber flooring (within 3mm over 3 metres) is an industry-standard reference, not a manufacturer-specified product performance metric - Shelf life information: Not specified by manufacturer; general portland cement product norms suggest 6–12 months when properly stored, but this is not a manufacturer-stated specification ## Related Products & Brand Context The Liquid Nails SLC50 Leveller is made by **Selleys**, an Australian brand well known across the home improvement and trade sectors for adhesives, sealants, fillers, and surface preparation products. The SLC50 sits within Selleys' flooring preparation range, categorised under **Home & Garden > Flooring Installation Materials**. Its full product name — Liquid Nails SLC50 Leveller — reflects Selleys' use of the Liquid Nails sub-brand for heavy-duty construction and bonding products, though the SLC50 itself is a cementitious compound rather than an adhesive. Within the Selleys range, the SLC50 is specifically positioned as part of the **Selleys Timber Flooring System**, meaning it is designed to work alongside other products in that system for preparing concrete substrates before timber floor installation. The "50" in the product name corresponds to its levelling depth capacity — it can level surfaces by up to 50 mm — which distinguishes it from thinner-build levelling compounds intended for minor surface correction only. Beyond that system grouping, the graph context does not name additional sibling products in the SLC50's immediate range, so no further Selleys levelling variants can be confirmed here. In terms of use-case adjacency, anyone using the SLC50 is almost certainly also dealing with concrete substrate preparation ahead of a flooring installation. That makes products such as concrete primers and bonding agents highly relevant companions, since Selleys itself recommends consulting the manufacturer on priming requirements before applying the SLC50. Timber flooring adhesives — likely from Selleys' own Liquid Nails flooring adhesive line — would typically follow once the levelled substrate has cured. Personal protective equipment, including safety glasses, nitrile gloves, and protective clothing, is also recommended during mixing and application. The SLC50 is suited to both interior and exterior use, which broadens its applicability beyond purely indoor flooring projects. Its self-smoothing, fast-set formulation positions it as a trade-oriented product where efficiency and substrate quality ahead of a final floor finish are the primary concerns.