- Admixture
- A material other than cement, aggregate and water added to a concrete mix, in small quantities, to modify its properties. In Australia admixtures are covered by AS 1478.1-2000.
- Integral waterproofing
- Waterproofing achieved by what is in the concrete itself, rather than by a layer applied to the surface of the hardened concrete. Nothing to puncture, lap or terminate, and coverage does not depend on access.
- Hydrogel admixture
- A preventative integral waterproofing admixture. It utilises the water of convenience in the mix to become part of the concrete matrix, so pores and capillaries are stopped from forming. The hydrophobic state is the stable state of the cured concrete — it is not a reaction waiting to be triggered. CLEVA CRETE 842 is a hydrogel admixture. See how it works.
- Crystalline admixture
- A reactive integral waterproofing admixture. It responds to water entering concrete in which a capillary network has already formed. It is a different category to a hydrogel admixture: crystalline technology acts after the fact, hydrogel technology acts during hydration. Read the full comparison in Hydrogel or crystalline? The difference is when the waterproofing happens.
- Water of convenience
- The mix water present in fresh concrete beyond what is strictly consumed by cement hydration. A hydrogel admixture uses it during hydration rather than leaving it to form the capillary network as it migrates out.
- Capillary network
- The interconnected pore structure formed in concrete as it hydrates and dries. It is the transport path for water, water vapour, chlorides and sulfates, which makes it the mechanism behind both leaks and reinforcement corrosion.
- Permeability
- How readily fluid moves through the concrete matrix. Lower permeability means a slower transport path, which is a durability outcome as much as a waterproofing one.
- Moisture vapour emission rate (MVER)
- The rate at which water vapour leaves a slab. Floor coverings and adhesives have limits, and exceeding them is what causes cupping, blistering and adhesive failure after handover.
- MAT test
- A surface moisture test on the cured slab: an impermeable sheet is sealed to the slab and left in place, per the plastic sheet method of ASTM D4263. CLEVA CRETE runs it over 72 hours on every 842 MVRA slab that is receiving a floor covering, to assess moisture movement at the surface where the flooring system will be installed, and documents the result.
- Moisture vapour emission rate surface test
- A surface test measuring the rate at which water vapour leaves a slab, set out as a secondary test method in Appendix B of AS 1884:2021, Floor coverings — Resilient sheet and tiles — Installation practices, and carried out in accordance with ASTM F1869. Where the 25-year moisture vapour warranty is required on 842 MVRA, this test is a prerequisite: CLEVA CRETE runs it, or the builder presents the full test report.
- Vapour barrier (under-slab)
- The polyethylene membrane laid under a slab on ground before the pour. In Australian practice both "vapour barrier" and "moisture barrier" often refer to this. It is a separate requirement and CLEVA CRETE does not replace it.
- Surface-applied topical moisture barrier
- A coating applied over a cured slab to control moisture vapour emission before floor coverings go down. This is the barrier that 842 MVRA removes from the build — except in wet areas, which are still waterproofed in the normal way.
- Applied membrane (external / tanking)
- A sheet or liquid waterproofing layer applied to the outside face of a below-ground structure. It is a hand-applied trade on a surface that becomes inaccessible once backfilled, and its failures concentrate at laps, terminations and penetrations.
- Hydrostatic pressure
- Pressure from standing groundwater against a structure. Below the water table it is continuous rather than incidental, which is why small defects become long-term leaks.
- Water table
- The level below which the ground is saturated. It moves seasonally, so a basement that is dry in one part of the year can be under pressure in another.
- Water-retaining structure
- A structure that holds water in service — tanks, reservoirs, detention and fire tanks, treatment structures. Loaded from the inside, constantly, which is a different problem to a basement. See water tanks.
- Waterstop
- A profile cast into a construction joint to interrupt water passing through the joint. Joints remain detailed items on an integrally waterproofed structure.
- Exposure classification
- The AS 3600 classification of the environment a concrete element sits in, which drives minimum strength, cover and mix requirements. An admixture is used within the exposure classification, not instead of it.
- Self-healing
- The capacity of concrete to close cracks that form after curing. CLEVA CRETE 842 self-heals cracks up to 0.66 mm in hardened concrete, in concrete of 32 MPa or greater with a water-cement ratio between 0.34 and 0.59 — a mechanism separate from the prevention of the capillary network during hydration.
- AS 1478.1-2000
- The Australian Standard for chemical admixtures for concrete, mortar and grout. CLEVA CRETE 842 admixtures are certified to it.
- Batch record
- Documentation issued per load showing what was dosed into that concrete. It is the difference between an auditable durability decision and a verbal assurance.
- Moisture egress warranty
- A warranty against moisture passing out through the concrete. The CLEVA CRETE warranty runs 25 years and covers materials and labour; most admixture warranties in the market cover materials only.
Still have a question? The FAQ covers dosing, verification and what the product does and does not replace.