choose the right render beads to prevent render cracking
The beading or trim used in an external render system might be more important than you think. Using the correct type of render beads for a rendered façade will ensure the best finished look, ensure durability and help protect the render from water damage, staining and cracking.
Render beads form and protect the edges and corners of external render, so it is important that it is as durable and looks as good as the render itself.
There are 34 different ProBead profiles and a huge range of colours– so how do you choose the right render bead? ProBead are PVC render beads, make in the UK from recycled plastic. They are through coloured bead, matched to our render colours that can be easily cut. Plastic render beads will not rust or bleed, and are as durable as the render. Order free sample render beads here.
Let’s look at how to choose the right render beads and detailing for a long-lasting rendered façade.
Bellcast Bead or Drip Bead
Bell cast beads allows any water running down the face of the render to drip straight off.
It is important to use the bellcast bead and not a stop bead, as the angle it creates stops water running back towards the wall underneath the bead. Using a bellcast bead in the correct place prevents damp getting into the render and can stop render cracking.
Angle beads reinforce the render system at the corners and returns, helping to reduce impact damage and keeping the render edges sharp. Angle beads eliminate the need to manually form corners on site, and can act as a guide to the depth when applying the render.
The ‘nose’ of an angle bead creates straight and crisp lines in the render finish, which is why ProBead uses high quality PVCu that does not warp, and our angle bead is supplied boxed to prevent bending or twisting in transit.
These can be up against window and door frames, soffits, copings, other claddings or building fabrics. A silicone sealant is usually ran along the return or back edge of the stop bead to prevent water ingress.
Stop beads can also be used to create ‘picture frames’ or decorative feature panels within the render.
Expansion beads, also known as movement joints, help to reduce the risk of cracking in rendered elevations with large surface areas. They also help to reduce the risk of cracking where different substrates or building materials join. It is important that expansion joints are used where two substrates join to eliminate cracking from differential movement. Ask our technical team for advice if you are designing a rendered façade with multiple materials.
Generally, expansion beads are placed over the movement joints present in the substrate. If no movement joints are present in the substrate, expansion beads will not perform correctly and will not reduce cracking.
Render bead colour
A thin edge, or ‘nose’ of the render bead can be seen outlining the building in most modern render systems, which is why ProBead is available in 18 stock colours, but we can make custom-colour beading to match in more than 65,000 colours. We can also custom colour render and masonry paint to match or complement other buildings, so can supply a complete render system solution for you.
Our ProWall rainscreen cladding and ProRend external wall insulation systems include specially developed beads, we also have ashlar detailing beads and meshed beads. Do ask our team if there particular detailing you are aiming to achieve with the rendered finish and we can help.
Order ProBead direct
Order direct from the manufacturer – we hold over a million metres of ProBead in stock and can deliver next day on standard coloured render bead. Made in the UK from recycled materials and an industry favourite, order coloured bead samples here. Ask about our render, cladding and insulation options for your project.