Gripset GP Primer

For porous building substrates where preparation is required before waterproofing or tiling, GP Primer consolidates the surface and stabilises porosity. It forms a high-adhesion bonding key across porous materials, ensuring that Gripset waterproof membranes and tile adhesives adhere reliably without premature water loss into the substrate.

How it works

GP Primer is a water-based general purpose primer that dries from a milky white liquid to a clear finish. It seals porous surfaces to prevent dust, rapid absorption, and surface suction from robbing moisture from overlying membranes, coatings, and adhesives. It is formulated to be compatible with the full suite of Gripset systems across both internal and external installations.

Numbers that matter

• 30-minute dry time: Fast-drying window at 23°C and 50% relative humidity, allowing waterproofing or tiling work to proceed with minimal downtime. Cool or humid conditions will extend this window.
• 8 to 10m² per litre coverage: Economical coverage rate per coat, helping estimating accuracy on large-scale masonry, screed, or concrete prep jobs.
• 1 to 2 coats: Single-coat application is standard for typical porous substrates, while two coats are required for highly porous or dusting surfaces like aerated concrete.

Where to use it

• Concrete and masonry: Suitable for cured concrete, concrete blocks, brickwork, and general masonry surfaces.
• Screeds and renders: Stabilises sand-cement screeds, renders, and aged screed surfaces.
• Aerated concrete: Consolidates highly porous and dusting surfaces including Hebel and aerated concrete blocks.
• Sheeting and board: Prepares compressed fibre cement sheeting and plasterboard for waterproofing and tiling systems.

Limitations

• Moisture limits: Do not apply over damp surfaces, substrates with elevated residual moisture, or areas subject to rising damp. For damp or high-moisture substrates, use Gripset E60 or Xpress H20 Primer Plus. Active moisture or rising damp must be treated with Gripset E60.
• Temperature boundaries: Do not apply when surface or ambient temperatures are above 35°C or below 5°C.
• Weather restrictions: Do not apply if rain is falling or imminent.
• Application purity: Must be applied neat. Do not dilute with water or solvent.

Preparation and application

• Cure windows: Allow new concrete to cure for a minimum of 28 days, and screeds or renders to cure for at least 7 days before priming.
• Surface cleanliness: Substrates must be clean, dry, smooth, and free from laitance, curing compounds, release agents, dust, oil, grease, wax, moss, algae, and existing coatings. Mechanical removal via grinding or abrasive blasting is required for structurally unsound layers.
• Defect remediation: Fill and level all pitted sections, voids, holes, and non-structural cracks prior to priming. Use Gripset 11Y enhanced repair mortar or RLA repair mortars.
• Application method: Apply neat using a brush or medium nap roller over the entire area of the intended system. Highly porous or dusting surfaces like Hebel or aged screeds require two coats to stabilise the surface.
• Overcoating: Ensure the primer is dry before applying any finishes. Install subsequent membranes or tile adhesives shortly after the primer dries to prevent site dust from contaminating the surface.
• Clean up: Wash tools in water while the primer is still wet.