Alkali-resistant primer systems

Dulux Weathershield Alkali Resistant Primer is the mandatory first coat under the Dulux Weathershield exterior acrylic system on new or unpainted cement render and concrete facades. Fresh cement render has a pH of 12–13 due to calcium hydroxide (portlandite) leaching from the cement binder during the carbonation process. Applying an acrylic topcoat directly to this alkaline substrate causes saponification — alkaline hydrolysis of the paint binder — leading to early adhesion failure, blistering, and peeling. The alkali-resistant primer neutralises this risk by providing a stable, bonded interface between the high-pH substrate and the acrylic topcoat. Applied in one coat at approximately 12–15 m²/L and allowed to cure before applying two coats of Dulux Weathershield Exterior Acrylic. Substrate must be cured for a minimum of 28 days before priming. Confirm current DFT, spread rate, and overcoat interval from the current Dulux Weathershield Alkali Resistant Primer TDS before specifying.

Wattyl Solagard Exterior Primer is the companion alkali-resistant primer for the Wattyl Solagard exterior acrylic coating system. It is designed for application on new cement render, concrete, brick, and masonry substrates where the high alkalinity of the substrate would cause saponification of a directly applied acrylic topcoat. Saponification — the alkaline hydrolysis of acrylic binder molecules — results in early adhesion failure and blistering, typically within 6–24 months of application. The Solagard Primer provides a stable bonded interface that resists this pH-driven attack and ensures adhesion of the subsequent acrylic topcoat coats. Applied in one coat on clean, cured, and dry substrate and allowed to dry before applying two coats of Solagard exterior acrylic. Minimum substrate cure 28 days for cement render. Confirm current product range, DFT, spread rate, and overcoat intervals from the current Wattyl TDS before specifying.

Haymes Prep'd & Primed Exterior Primer is an Australian-manufactured alkali-resistant acrylic primer for cement render, concrete, brick, and masonry facades. Haymes manufactures and distributes primarily through Victoria and New South Wales, with growing trade distribution nationally. The primer provides the essential alkali barrier between fresh cement render (pH 12–13) and the subsequent acrylic topcoat, preventing saponification failure of the binder. It is specified as the first coat under Haymes exterior acrylic systems on new render and bare masonry. Haymes technical support provides project-specific advice for specification on strata and commercial facade repainting works. Confirm current product designation, DFT requirements, spread rate, and compatibility with the chosen Haymes acrylic topcoat from the current Haymes TDS before specifying.

Taubmans Concrete & Masonry Primer Sealer is an alkali-resistant acrylic primer and sealer for cement render, concrete block, brick, and masonry facades. The product provides both alkali resistance — neutralising the pH 12–13 environment of fresh cement render — and a sealing action that reduces substrate porosity and provides a uniform absorption base for the subsequent acrylic topcoat. Penetrating primer technology allows the product to consolidate slightly dusty or porous concrete and masonry surfaces before topcoating. Taubmans is part of the PPG group and is widely stocked nationally through hardware and trade channels. Confirm current product designation within the Taubmans primer range, DFT, spread rate, and compatibility with your chosen Taubmans exterior topcoat from the current Taubmans TDS before specifying.

Solver Exterior Alkali Resistant Primer is an acrylic-based exterior primer designed for cement render, concrete, and masonry substrates with high alkalinity. Solver Paints has strong regional distribution across Queensland, New South Wales, and Victoria through independent paint retailers and trade merchants. The product addresses the fundamental challenge of coating fresh or recently cured cement render: the cement binder produces a highly alkaline substrate (pH 12–13) that causes saponification failure in directly applied acrylic topcoats. The alkali-resistant primer provides a stable bonded interface, allowing the subsequent acrylic topcoat to achieve design DFT and service life. Confirm current product designation within the Solver exterior range, DFT, spread rate, and compatibility with the chosen Solver topcoat product from the current Solver Paints TDS before specifying.

TODO: owner confirm — British Paints PREP 4in1 Water Based (closest confirmed AU product) provides priming, sealing, undercoating, and stain-blocking functions in a single coat. Alkali resistance is NOT specifically claimed for this product on the British Paints AU product page as of verification date. If alkali resistance on new cement render is a specification requirement, confirm with British Paints technical whether this product is suitable as the primer on fresh or unpainted cement render before specifying. British Paints (part of the PPG group) is widely distributed nationally through Mitre 10, Home Hardware, and independent paint retailers. Coverage ~14 m²/L confirmed from fetched product page. Confirm current product formulation, DFT, spread rate, and compatibility with your chosen exterior topcoat from the current British Paints TDS before specifying.