Dashing Information – Application Guide
Applying the gravel dashing
Dashing aggregates supplied by Derbyshire Specialist Aggregates do not require any further washing at this stage.
Ensure that the moisture content within the aggregates will not affect the performance of the applied render.
With dry-dash finish and certain textured finishes it is essential for the final coat to remain soft for a longer period. This can be assisted through reducing the suction of the undercoat by more thorough wetting down, or including a water-retaining admixture in the final render coat.
No aggregate should be applied directly from the bag that it was supplied in.
Any fines contained in the bag will usually fall towards the bottom of the bag and this can cause patching when applied where an area with a higher percentage of fines will differ in texture, colour and finish to an area dashed with aggregates containing little or no fines.
All dashing aggregates should be decanted from the bags into a clean drainable container (i.e. a plasterer’s bath) and blended with 3 to 4 other bags ensuring that the colour and any fines are mixed evenly within the container prior to application. As the dash is used add more bags to the bath or barrow, thereby blending in more as you go, this will give the best and most consistentfinish.
Do not use picked up material that has not adhered to the wall, this will tend to be discoloured and not graded the same as fresh material and will cause patching.

Area prepared for dashing

Dashing being applied