Waterproof Board Testing

Waterproof board testing is conducted in accordance with relevant standards and industry specifications. Scientific testing and analysis are performed on water absorption and volume swelling rate, wet swelling and dry shrinkage performance, impermeability pressure and moisture vapor transmission coefficient, surface water resistance, freeze-thaw cycle resistance, and chemical corrosion resistance, objectively assessing the product quality grade. A detailed test report is issued within 7-10 working days, providing a basis for manufacturers' quality control and downstream users' product acceptance.

Testing Items

Water absorption and volume swelling rate: These are core indicators for evaluating the durability and dimensional stability of waterproof boards. By measuring the percentage increase in mass of the board after immersion in water for a specified time (water absorption) and the dimensional changes in thickness and length directions (volume swelling rate), the deformation resistance and structural stability of the board in humid environments can be determined.

Wet swelling and dry shrinkage performance: Simulates the dimensional stability of the board caused by periodic humidity changes in actual service environments. By repeatedly cycling the specimen under specific temperature and humidity conditions (such as high humidity and dry), and measuring its final dimensional change rate, the ability of the board to resist environmental humidity stress and avoid cracking or warping is evaluated.

Impermeability pressure and moisture vapor transmission coefficient: The impermeability pressure test reflects the static ability of the board to resist the penetration of liquid water, usually by applying increasing water pressure until seepage appears on the back face. The moisture vapor transmission coefficient measures the ability of the board to transmit water vapor, which is crucial for wall structures that need to "breathe" or for specific application scenarios (such as the negative side of basements).

Surface water resistance: Evaluates the effect of liquid water (such as rainwater and condensate) remaining on the board surface on its surface coating, color, gloss and physical properties. Usually, the water droplet standing method or surface wetting angle measurement is adopted to determine its surface hydrophobicity and stain resistance.

Freeze-thaw cycle resistance: Targets boards that may be used in cold regions, simulating the destructive process of water freezing and expanding and melting and shrinking in the pores of the material. After a specified number of freeze-thaw cycles, the mass loss rate, strength loss rate and appearance changes are tested to verify its long-term weather resistance.

Chemical corrosion resistance: Tests the performance retention of the board after contact with chemical media such as acids, alkalis and salts. By immersing the specimen in chemical solutions of standard concentration for a certain time, observing surface changes and testing the attenuation of physical and mechanical properties, its applicability in special industrial or coastal environments is evaluated.

Testing Scope

Cement-based waterproof boards: Such as fiber cement boards and calcium silicate boards, whose waterproofness is enhanced by incorporating polymers, hydrophobic agents or densification processes. Testing focuses on their water absorption, impermeability and long-term stability in alkaline environments.

Polymer-modified waterproof boards: Including membrane and sheet products such as PVC (polyvinyl chloride), TPO (thermoplastic polyolefin) and HDPE (high-density polyethylene). Testing focuses on joint peel strength, low-temperature flexibility, root resistance (for green roofs) and artificial weathering aging performance.

Metal composite waterproof boards: Such as aluminum-magnesium-manganese alloy panels and coated aluminum-zinc steel plate waterproofing systems. In addition to the corrosion resistance of the base material, the weather resistance of the coating (such as QUV aging), coating adhesion, and the air tightness and water tightness of the panel seam lock system need to be emphasized.

Wood-plastic composite waterproof boards: Composed of wood fiber and plastic, commonly used for outdoor decks and exterior wall cladding. Core test items include water absorption thickness swelling, flexural performance retention (after boiling or freezing treatment) and mold resistance grade.

Stone and ceramic waterproof boards: Such as stone treated with hydrophobic agents and full-body tiles. Their surface water absorption, stain resistance (easy cleaning) and wet bonding strength with the back adhesive material are tested to prevent hollowing and falling off.

New polymer waterproof boards: Such as spray-applied quick-setting rubber asphalt and non-curing rubber asphalt waterproof boards. Their self-healing property, full bonding rate with the substrate, resistance to water channeling, and performance under long-term hydrostatic pressure need to be tested.

Testing Methods

Immersion method (GB/T 17657): Used to determine water absorption and thickness swelling rate. A specimen of specified size is completely immersed in distilled water at (23±2) ℃ for a specified time (such as 24 h or 48 h), then removed, surface moisture wiped off, immediately weighed and measured, and the change rate is calculated. This is the most basic and widely used quantitative method.

Impermeability test (GB/T 328.10): Mainly for building waterproofing membranes. An impermeability tester is used to continuously apply increasing water pressure (or vacuum negative pressure) on the upper part of the specimen, observing whether seepage appears on the back face within the specified time, and recording the pressure value at the onset of seepage as the impermeability pressure.

Moisture vapor transmission cup method (GB/T 17146): Used to determine the water vapor transmission rate. The specimen is sealed on the mouth of a permeability cup containing a desiccant or distilled water, placed in a constant temperature and humidity environment, and the mass change of the cup is weighed periodically to calculate the amount of moisture vapor transmission per unit time, per unit area and per unit water vapor pressure difference.

Cyclic freeze-thaw test (GB/T 50082): Saturated specimens are placed in a freeze-thaw test chamber for rapid freeze-thaw cycles between -20 ℃ and +20 ℃ (or a specified range). After each certain number of cycles (such as 25 or 50 cycles), the mass loss and dynamic modulus of elasticity (or compressive strength) loss of the specimen are tested to evaluate its durability.

Chemical resistance test (ISO 175): The specimen is partially or completely immersed in chemical reagents of standard concentration (such as acid, alkali and salt solutions) and soaked at specified temperature and time. After completion, its corrosion resistance grade is comprehensively evaluated through appearance inspection, mass change measurement and mechanical property testing.

Artificial weathering accelerated aging test (GB/T 16422.2): A xenon arc lamp or UV fluorescent lamp is used to simulate climatic factors such as sunlight, rain and condensation to accelerate the aging of the board and its coating. By periodically testing color change (ΔE), gloss retention, chalking grade and mechanical properties, the outdoor service life is predicted.

Testing Standards

Domestic Standards:

1. GB/T 17657-2022, Test methods of evaluating the properties of wood-based panels and surface decorated wood-based panels

2. GB 18580-2025, Indoor decorating and refurbishing materials — Limit of formaldehyde emission of wood-based panels and finishing products

3. GB/T 1931-2009, Method for determination of moisture content of wood

4. GB/T 1936.1-2009, Method of testing in bending strength of wood

5. GB/T 4823-2013, Defects in sawn timber

International Standards:

1. ISO 12460-1, Determination of formaldehyde emission of wood-based panels — Part 1: 1 m³ chamber method

Note: The applicable standard can be selected according to the product use and customer trade requirements; standards agreed in the contract take precedence over general standards.

Testing Instruments and Equipment

Electronic balance and vernier calipers: Used to precisely measure the mass change (accuracy 0.01 g) and dimensional change (accuracy 0.02 mm) of the specimen before and after immersion, and are essential tools for calculating basic parameters such as water absorption and swelling rate. They require regular calibration to ensure data accuracy.

Building material impermeability tester: Composed of a pressure control system, permeability molds and specimen holding devices. It can provide stable and increasing water pressure (usually 0-2.5 MPa) to test the impermeability grade of boards, mortars or concrete specimens, and automatically record the seepage pressure and time.

Constant temperature and humidity test chamber: Used to provide standard testing environments (such as temperature 23±2 ℃, relative humidity 50±5%) or to perform high/low temperature and damp heat cyclic tests. It is the basic environmental equipment for wet swelling and dry shrinkage, moisture vapor transmission and constant temperature curing tests.

Freeze-thaw cycle testing machine: Can automatically and programmatically control the temperature to cycle rapidly within a set range (such as -20 ℃ to +20 ℃), with automatic temperature measurement and thawing functions. Advanced equipment integrates a dynamic modulus of elasticity measuring device that can monitor performance attenuation in real time without moving the specimen.

Xenon arc aging test chamber: Simulates the solar spectrum through a filter system and controllably simulates humid environments such as rainfall and condensation. Equipped with sensors and closed-loop control systems for irradiance, black panel temperature and chamber humidity, it is key accelerated aging equipment for evaluating the weather resistance of boards and coatings.

Tensile testing machine and peel strength fixtures: Used to test the tensile strength, elongation at break and joint peel strength of waterproof boards. It needs to be equipped with dedicated fixtures suitable for sheets and membranes, and be able to test at different temperatures (such as low temperature) to comprehensively evaluate their mechanical properties.