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Tile Adhesive Usage Guide

Tile adhesive (commonly called "gum sand" in Hong Kong) is a pre-mixed dry mortar — just add water and mix. It is used to bond tiles to walls or floors. Compared to traditional cement-sand mix, tile adhesive uses thin-bed application; the actual bed thickness depends on the tile, notched trowel, substrate condition, and product TDS.

The formula for tile adhesive usage is: tiling area (m²) × application thickness (mm) × consumption rate (kg/m²/mm). Consumption rates vary by product, generally ranging from 1.1-1.5 kg/m²/mm. Please refer to each product's TDS for exact figures.

Key factors affecting tile adhesive usage include:

• Tile size — tile size affects notched-trowel selection and the resulting adhesive-bed thickness. Enter the thickness adopted for the project and refer to the product TDS and engineering team's decision.
• Substrate flatness — uneven substrates require more adhesive to compensate.
• Tile back texture — tiles with deep grooves on the back will increase usage.
• Application technique — different installers have varying application habits. We generally recommend budgeting about 20% for wastage.

For a detailed comparison of tile adhesive vs cement-sand mix, read our guide: Tile Adhesive vs Cement-Sand Mix: Which Is Better for Tiling? Use the calculator tool below to calculate usage for a specific product.

Browse all tile adhesive products: Tile Adhesive Collection

Grout Usage Guide

Grout is used to fill the gaps between tiles. Beyond aesthetics, it also prevents moisture penetration and reduces mould growth. Different grout types (such as CG1, CG2, CG2WA, etc.) vary significantly in water resistance and durability.

The formula for grout usage is: (tile length + tile width) × tile thickness × joint width ÷ (tile length × tile width) × calculation factor × area. The calculation factor varies by product, generally around 1.5-1.7.

Key factors affecting grout usage include:

• Tile size — smaller tiles (such as mosaics) require more grout because the total joint length per unit area is longer.
• Joint width — wider joints mean more grout. Indoor tile joints are typically about 2-3mm, while rustic or outdoor tiles can be 5-10mm.
• Tile thickness — thicker tiles create deeper joints, increasing usage accordingly.

For more information on grout types and selection tips, read our guide: Popular Grout Brands in Hong Kong.

Browse all grout products: Grout Collection

Waterproofing Cement Usage Guide

Waterproofing cement (flexible waterproofing coating) is a brush-applied waterproofing material commonly used in bathrooms, kitchens, and rooftop waterproofing projects. Applied by roller or brush on the substrate surface, it forms a flexible waterproof layer when cured. Compared to the traditional method of mixing SBR bonding agent with cement and sand, waterproofing cement is easier to use and delivers more consistent quality.

A waterproofing-product TDS may state consumption per coat, per millimetre, or as an area covered per pack. The calculator applies the unit and formula stated for the selected product.

Key factors affecting waterproofing cement usage include:

• Waterproofing area — for bathrooms, calculate floor area plus wall turn-up height (generally recommended at least 1.8m high). Full-height waterproofing is recommended for shower areas.
• Number of coats or total thickness — follow the selected product TDS and project requirements; manufacturers do not all express this in the same way.
• Product type — different brands and models of waterproofing cement have varying consumption rates per coat. Please refer to the TDS for exact figures.

For a detailed comparison of waterproofing cement vs SBR bonding agent, read our guide: Flexible Waterproofing Cement vs SBR Bonding Agent.

Browse all waterproofing products: Waterproofing Cement Collection

Self-Levelling / Floor Screed Usage Guide

Self-levelling compound and floor screed are both floor-levelling materials: self-levelling is poured and flows level on its own, while floor screed is hand-troweled flat. Both are calculated the same way, driven mainly by application thickness.

The usage formula is: floor area (m²) × thickness (mm) × coverage rate (kg/m²/mm), divided by the pack weight for the number of bags. Self-levelling coverage is typically 1.5–1.9 kg/m²/mm, and floor screed around 1.7–1.8 kg/m²/mm (lightweight insulating grades lower, ~0.9). See each product's TDS for the exact figure.

Main factors affecting usage:

• Application thickness — thin smoothing (e.g. base prep before SPC/vinyl) uses less; thick filling of large drops uses more.
• Floor level difference / flatness — the bigger the drop, the greater the average thickness and usage.
• Product type — underlayment, overlayment, waterproof or insulating grades have different coverage rates; follow the TDS.

To learn more about choosing and installing self-levelling, see our complete self-levelling guide and self-levelling underlayment guide.

Browse the full range: self-levelling range, floor screed range

How to Use

1. Select a product from the list below and click "Calculate Usage".
2. Enter the tiling area or waterproofing area (supports automatic ft² and m² conversion).
3. Adjust the application thickness or joint width, and select an applicable scenario or method where the product provides one.
4. The system calculates the required weight and package quantity, using a product-specific default wastage percentage that can be adjusted.
5. To order or enquire, click "WhatsApp Wah Hing" to contact us directly.

FAQ

How do I calculate tile adhesive usage?

Tile adhesive usage formula: tiling area (m²) × application thickness (mm) × consumption rate (kg/m²/mm). Application thickness depends on the tile, notched trowel, substrate condition, and project requirements. Products with a TDS-stated minimum use it as a reference preset; products without one require user input. Consumption rate varies by product — please refer to the product TDS. We recommend budgeting about 20% extra for wastage.

How much area can one bag of tile adhesive cover?

Coverage depends on the pack weight, TDS consumption rate, and bed thickness adopted for the project; it should not be fixed from tile size alone. Select the specific product below to calculate it.

What is the difference between tile adhesive and cement-sand mix?

Tile adhesive is a pre-mixed dry mortar using thin-bed application, with typical thickness of 3-10mm — far less than traditional cement-sand mix (usually 15-20mm or more). Tile adhesive provides stronger adhesion, faster application, and may be more cost-effective overall. For a detailed comparison, read our guide: Tile Adhesive vs Cement-Sand Mix: Which Is Better for Tiling?

How to use tile adhesive?

In brief: clean the substrate and ensure it is structurally sound; mix tile adhesive with water to a smooth paste according to TDS instructions; apply evenly on the substrate using a notched trowel; press tiles into place within the open time. For detailed application steps and considerations, read our guide: Tile Adhesive vs Cement-Sand Mix.

How much grout do I need?

Grout usage formula: (tile length + tile width) × tile thickness × joint width ÷ (tile length × tile width) × calculation factor × area. Density factor varies by product, generally around 1.5-1.7. We recommend budgeting about 20% extra for wastage.

Is grout waterproof?

Standard grout (CG1 grade) is not waterproof. For waterproofing capability, choose CG2WA grade grout, which contains water-repellent additives that significantly reduce water absorption, making it suitable for bathrooms, kitchens, and other wet areas. For more details, read our guide: Popular Grout Brands in Hong Kong.

How do I calculate waterproofing cement usage?

A waterproofing-product TDS may calculate consumption per coat, per millimetre, or by area covered per pack. The calculator follows the selected product's TDS unit, application scenario, and packaging; the wastage percentage can be adjusted.

How many coats of waterproofing are needed for a bathroom?

The coat count, thickness per coat, and total thickness must follow the selected product TDS and project requirements. The calculator uses only scenarios and values stated for that product; it does not replace engineering judgement with a universal coat count.

What is the difference between waterproofing cement and SBR bonding agent?

Waterproofing cement (flexible waterproofing coating) is a ready-to-use or pre-mixed product — convenient to apply with consistent quality, and flexible enough to bridge hairline cracks. SBR bonding agent must be mixed with cement and sand on site, relying on the installer's experience for the correct ratio, making quality harder to control. For a detailed comparison, read our guide: Flexible Waterproofing Cement vs SBR Bonding Agent.

How to convert between square feet and square metres?

1 square metre (m²) = 10.764 square feet (ft²). For example: 150 sq ft ≈ 13.94 m². The Wah Hing material calculator supports both ft² and m² input with automatic conversion.

How is self-levelling / floor screed usage calculated?

Self-levelling and floor screed usage formula: floor area (m²) × thickness (mm) × coverage rate (kg/m²/mm), divided by the pack weight. Self-levelling coverage is typically 1.5–1.9 kg/m²/mm and floor screed around 1.7–1.8 (lightweight insulating ~0.9); see the product TDS for the exact figure. Allow about 20% wastage.