Thistle Bonding Coat is a gypsum undercoat plaster for use on low suction background e.g. brickwork, block work or concrete, gyproc plasterboard, expanded metal lath, or surfaces treated with bonding agent finish off with a final coat of Thistle Multi-Finish. Bonding coat provides a smooth, inert, high quality surface to internal walls and ceilings, and a durable base for the application of decorative finishes. Bonding coat is a lightweight, retarded hemihydrate, pre-mixed gypsum plaster, incorporating exfoliated vermiculite aggregate, requiring only the addition of clean water to prepare it for use.

Key Feature

• Easy to spread
• Smooth
• Easier to rule and darby

Application
Bonding coat should be applied with firm pressure, built out to the required thickness, ruled to an even surface and lightly scratched to form a key for 2mm Thistle Multi-Finish. If Bonding Coat and a finish plaster are to be applied to Gyproc plasterboard, Gyproc joint tape should be used to reinforce joints and angles. Any gap between boards exceeding 3mm should be pre-filled and joint taped with Thistle Multi-finish.

Coverage / Specification
A 25kg bag of Bonding coat will cover 2.75 m² at 11mm thickness and approximately 1.5 - 2 hours setting time. Complies with EN 13279-1, type B4/20/2 & C3/C20

Mixing
Bonding coat is pre-mixed with aggregate and only clean water needs to be added to prepare it for use. Mixing should be carried out in clean bucket or bath. Excessive mechanical mixing should be avoided. Tools and water used in mixing must be clean. Contaminations from previous mixes can shorten the setting time in turn reduce the strength of plaster when set.