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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 with typical thickness of 3-10mm, requiring significantly less material while providing stronger adhesion and easier application.

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 — larger tiles require thicker application, increasing usage. Small tiles (300×300mm or below) typically need about 3mm, medium tiles (300×600mm) about 6mm, and large tiles (600×600mm and above) about 8-10mm.
• 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) × density factor × area. The density 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.

The formula for waterproofing cement usage is: waterproofing area (m²) × consumption rate per coat (kg/m²) × number of coats. Consumption rate per coat varies by product, generally ranging from 0.7-2.0 kg/m².

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 — a minimum of 2 coats is generally recommended for bathrooms, with each coat allowed to dry before applying the next. High-risk areas may require 3 coats.
• 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

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 application thickness, joint width, or number of coats as needed.
4. The system automatically calculates the required weight and number of bags, including a 20% wastage allowance.
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 tile size: small tiles (300×300mm or below) about 3mm, medium tiles (300×600mm) about 6mm, large tiles (600×600mm and above) about 8-10mm. 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?

This depends on packaging weight and application thickness. With a typical 40kg bag: at 3mm thickness (small tiles) it covers about 11-12m², at 6mm thickness (medium tiles) about 5-6m². Please refer to the product TDS for exact coverage.

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) × density 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?

Waterproofing cement usage formula: waterproofing area (m²) × consumption rate per coat (kg/m²) × number of coats. Typically 2 coats for bathrooms, 2-3 coats for pools or water tanks. Consumption rate varies by product, generally ranging from 0.7-2.0 kg/m²/coat. Area must include floor area plus wall turn-up height. We recommend budgeting about 20% extra for wastage.

How many coats of waterproofing are needed for a bathroom?

A minimum of 2 coats is generally recommended, with each coat allowed to dry before applying the next. Apply alternate coats in perpendicular directions. For high-risk areas (such as shower zones and around drain outlets), a 3rd coat or additional waterproofing tape may be applied for reinforcement.

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.