What is the difference between dry dash and wet dash?
Dry dashing and wet dashing are very similar methods of external wall rendering. In dry dashing, the cement and sand mixture is applied to the walls and the pebbles are stuck on. With wet dashing, the stones are added to the cement and sand mixture before it is applied to the walls.
What Colour is wet dash?
Wet Dashing It is usually white or grey in appearance (depending on the cement used).
What is wet dash?
Roughcast (also called ‘wet-dash’ in Cumbria and ‘harling’ in Scotland) is a render with a coarse finishing coat containing gravel thrown in a premixed state onto a wall. It is distinct from pebble dash (or ‘dry dash’) in which the aggregate is applied separately onto wet plaster.
What is dry render?
Dry rendering typically involves placing the materials to be rendered in a steam-jacketed rendering system that is placed under vacuum. Screening and centrifugation are used to separate the fats and oils from the solids, which contain the protein matter.
How long does dashing take to dry?
24 hours
The material cures and dries by hydration and evaporation and is usually sufficiently cured after 24 hours at 65%RH. Lower temperatures prolong the drying time, whilst higher temperatures accelerate drying.
What is the mix for roughcast?
A standard mix for the roughcast would be 1 part cement to 2-3 part sand mixed with clean water. The stone or aggregate as it is known is then put into the mix. This is usually a 4-5 part aggregate to add to the above mix.
What is the difference between roughcast and pebbledash?
For pebbledash, clean material is thrown at the freshly plastered surface then pressed in, so the colour of the material is visible. For roughcast, on the other hand, this material is mixed with mortar and then thrown at the surface, so all the material is coated with the mortar.
Can you paint pebble dash walls?
Alternatively, can you paint pebbledash? Yes, luckily you can paint over pebbledash! Having said this, it is known as one of the most difficult exterior surfaces to paint, so it is important to properly research this before undertaking to ensure you get the finish you are looking for.
Why are houses pebble dashed?
This exterior wall finish was made popular in England and Wales during the 1920s, when housing was in greater demand, and house builders were forced to cut costs wherever they could, and used pebbledash to cover poor quality brick work, which also added rudimentary weather protection.
Can I plaster over Pebble Dash?
Technically speaking, you can render over the top of pebble dash as long as it isn’t damaged. However, there are a number of reasons why this isn’t recommended: It could add unnecessary stress to the walls.
What is a dry dash finish?
Dry Dashing is a traditional decorative rendering technique that provides a tough, durable, long-lasting, cost-effective and almost maintenance-free finish to exterior wall surfaces.
How long does Pebble Dash take to dry?
Pebble Dashing the Wall Apply the initial layer of the render with a trowel. Make a very smooth coat of render. You also may want to rake or score it to help the next layer adhere better. Leave it to dry overnight or for about 24 hours.