Weldcrete | Waterproof Bonding Agent

REQUIREMENT:

Bonding of concrete, construction joints, cement renders, toppings etc.
Chemical and/or water resistant renders & toppings for interior or exterior wall or floors. (See also “CALTITE”)
Damp resisting layers / moisture barrier.
Primer / undercoat for paintwork to resist rising damp.
Improved chemical resistance for industrial flooring, screeding & toppings.
Linings & effluent ducts.
Levelling floors, patching and repairing damaged concrete areas.
Corrosion protection of steel reinforcing rods in concrete and of steel structures.
Nosing for stairs indoors and outdoors.
Water resistant adhesive for attachment of tiles, glass, aggregates, steel, mosaics, etc.

PRODUCT TO USE:

WELDCRETE

Water Resistant Concrete Bonding Agent & Additive

EFFECTS: Mortars and concrete

Excellent adhesion to substrates, including very dense or waterproof concretes.
Excellent resistance to water and water vapour.
Resists dampness, discolouration and damage of paintwork subject to rising damp.
Mixes may be applied in thin layers, including “feather-edging”.
Increased toughness and flexibility.
Increased resistance to certain chemicals.

HOW TO USE:

PREPARATION:
All surfaces must be clean. Loose material such as flaking, limewash, paint, distemper, etc must be removed. Mould oil should be cleaned from shuttered concrete and rust removed from all metalwork.

APPLICATION:

Damp Resisting Barrier / Undercoat:

Brush neat WELDCRETE on to the cleaned, pre-dampened substrate in at least two applications. Allow drying between coats and apply at right angles to each other to avoid pin holes. Severe damp may require additional coats. After final coat is thoroughly dried apply water based paint directly over the WELDCRETE undercoat(s).

WELDCRETE Modified Mortars (Renders, Toppings, etc).

Mixing procedure is similar to that used for conventional mixes, gauging water being partially or completely replaced by WELDCRETE at the rate of 3-7 litres per 20kg bag of cement. The higher level is used for thin screeds where maximum performance is required. Avoid entraining air in the mix.

BONDING AGENT:

Brush neat WELDCRETE thoroughly into the pre-dampened substrate at the rate of approx. 6m² per litre and apply renders or toppings directly while the WELDCRETE bond-coat IS STILL WET.

ALTERNATIVE METHOD:

Slurry 1 part of WELDCRETE to 2 parts of fresh, neat cement (by volume) and brush thoroughly in to the pre-dampened substrate, applying subsequent toppings or renders directly. Coverage of WELDCRETE slurry is approx 2-3m² per litre of slurry.

NOTE:

DO NOT allow WELDCRETE bond-coat to dry out or harden (approx 20-30 minutes). Best results are achieved by application of fresh renders, toppings etc. to WET WELDCRETE. If drying occurs, re-apply fresh WELDCRETE before proceeding.

Contact Cementaid Technical Service for advice and Technical Bulletin on specialist applications or requirements.