K Rend & silicone rendering

What silicone render actually is

Silicone render — K Rend being the best-known name for it — is a modern, factory-made system that replaced the old sand-and-cement-and-paint approach. The colour is mixed right through the top coat rather than painted onto it, so a scratch or a chip doesn't show up as a white scar, and you're not repainting the house every five or six years.

It's also water repellent but breathable. Rain beads off and runs away, while moisture inside the wall can still get out — which is exactly what you want on a British house, and exactly what a lot of older render systems got wrong.

The catch is that a bag of silicone render is only the last two days of the job. Everything that determines whether it still looks right in fifteen years happens before that: what's underneath it, what it's bonded to, where the beads sit and where the water goes.

How we build it up

A render system is a sequence, and skipping a step in it is how you end up with a cracked, banded or blown elevation. Ours runs like this:

1. Survey the substrate. We check what we're rendering onto — brick, block, existing render, board — and hammer-test anything already on the wall.
2. Prep and make good. Old coatings off, blown areas cut back, cracks dealt with at source, and anything organic killed off rather than buried.
3. Beads and stops. Corner beads, bell casts, stop beads and movement joints set out and levelled. This is the bit that makes an elevation look sharp or look homemade.
4. Basecoat and mesh. A proper polymer basecoat with mesh where the system calls for it — around openings especially, because that's where cracks start.
5. Top coat. Applied wet-on-wet across a full elevation, gauged consistently so there's no banding, and finished to the texture you've chosen.
6. Detailing and clean down. Cills, reveals, verges, drips and junctions finished properly, then everything washed off and taken away.

Systems, finishes and colours

We work in K Rend, Weber (Saint-Gobain), Johnstone's Stormshield and EcoRend systems. All offer a wide standard colour range plus bespoke matching, and several textures:

• Silicone thin coat (1.5mm / 2mm) — the modern smooth-ish finish most people picture. Crisp, contemporary, forgiving on flat elevations.
• Scraped texture / monocouche — a slightly heavier, traditional grain that hides minor substrate movement well.
• Dry dash / pebbledash receiver — where you're matching an existing house or a conservation requirement.
• Brick slip and feature detailing — plinths, banding and contrast panels where the design calls for it.

On colour: whites and off-whites look sharp but show more; mid greys and warm greys are what most people in the North West end up choosing, and they weather kindly. We'll bring samples out and look at them against your brick, your roof and your neighbours' houses before you commit — not off a phone screen.

What we'll render onto

• Brick and blockwork, new or existing
• Sound existing render or pebbledash (subject to survey)
• Render carrier board on timber frame and SIPs
• Insulated render systems and EWI carrier boards
• Extensions tying into an existing rendered elevation

Why renders fail — and how we avoid it

Almost every failed render we get called out to comes down to one of four things, and none of them are the fault of the product in the bag:

• Cracking at openings — no mesh, or mesh not carried diagonally off the corners of windows and doors.
• Blowing and hollow patches — rendered onto something that was never sound, or onto a dusty, unprimed surface.
• Green and black staining — water not being thrown clear, usually a missing bell cast or drip detail, or a cill that discharges straight down the wall.
• Colour banding — inconsistent gauging or a dry edge, from an elevation broken across two days.

Our quotes include the work needed to avoid all four. If you're comparing prices and ours differs from another, do ask us why — we're always happy to walk you through what's included and let you make an informed decision.