Spend ten minutes Googling house rendering and you’ll find someone swearing it causes damp, someone else insisting it’ll crack within a year, and another person on a forum who reckons he can do his whole house himself with a bag of sand and cement.
Most of this advice isn’t wrong out of malice – it’s just out of date. A lot of it comes from old sand and cement render that failed decades ago, or from jobs that went wrong because they were done badly, not because rendering itself is the problem. Modern systems are a different animal: more flexible, more breathable, and far better performing, as long as they’re installed properly.
So here are the 10 myths we hear most often from homeowners across Greater Manchester, and what’s actually true.
Myth #1: You can’t render an old house
You can. We do it regularly. What matters isn’t the age of the property – it’s understanding the building before anyone picks up a trowel. How were the walls built? What condition are they in? What does the property need to keep doing once it’s rendered?
Older homes often do brilliantly with modern breathable render systems, and in many cases External Wall Insulation can transform both how the house looks and how much it costs to heat. The key is a proper survey first, not a one-size-fits-all approach. Period properties deserve better than guesswork.
Myth #2: Insulated render causes damp
This one comes up in almost every conversation we have about EWI, so let’s be clear: insulated render doesn’t cause damp when it’s designed and installed correctly.
When people do get moisture problems, it’s almost always down to poor installation, poor ventilation, or an existing issue in the property that was never dealt with. The insulation gets the blame because it’s the newest thing on the wall.
A good EWI system works with the building – improving thermal performance while still letting moisture escape where it needs to. Pair that with decent ventilation (extractor fans, trickle vents where needed) and you’ve got a warmer, drier home, not a damper one.
Myth #3: You can’t render in winter
Rendering doesn’t pack up for the year the moment the clocks go back.
Yes, temperature and weather matter. But modern render systems can go on through much of the winter, provided conditions are right and manufacturer guidelines are followed. We keep a close eye on temperature, rainfall and drying conditions to make sure the render cures properly.
In short: it’s not about the season, it’s about the conditions on the day. And in Manchester, we’ve had plenty of practice working around the weather.
Myth #4: Windows should be sprayed before rendering starts
Surprisingly common, this one, and it’s the wrong way round.
Windows should usually be fitted before rendering starts, but sprayed after the rendering is finished. Fitting them first means the render can be finished neatly against the frames, giving you a cleaner look and a better weatherproof seal. Spraying them last means they’re not at risk of getting damaged or splattered while the render’s going on.
Myth #5: All render cracks over time
If you’ve seen a cracked, patchy rendered house, chances are it was old sand and cement render, and that reputation has stuck.
Modern systems are far more flexible and designed to handle the normal movement every building goes through. Combine that with proper preparation, reinforcement mesh where it’s needed, and correct installation, and the risk of cracking drops dramatically.
No external finish is immune to genuine structural movement, but nothing is. However, cracking is not something you should just expect as part of the deal.
Myth #6: You can always render over old render
Tempting, isn’t it? Skip the removal, save some money, crack on.
Sometimes it works. Sound, well-bonded render can be a perfectly good base depending on its condition and the system going over it. But loose, hollow or damaged render needs to come off completely – rendering over it just means paying twice when the new coat fails along with the old one.
That’s why we inspect the existing render properly before recommending anything. Every wall is different, and getting it wrong costs more than checking first.
Myth #7: Rendering is an easy DIY job
Rendering looks straightforward right up until you try it.
Getting a smooth, even finish takes experience, the right tools, and a feel for how different products behave as they go on and as they cure. And the finish is only half the job – the preparation underneath matters just as much. Mistakes made before the render even goes on can undermine its performance for years.
A professional installer isn’t just applying a coating. They’re preparing the substrate properly, using compatible systems, and following manufacturer specs so the render actually performs the way it’s supposed to. That’s what you’re paying for.
Myth #8: Rendering is too expensive for the average homeowner
Rendering is an investment, but it’s often more affordable than people assume.
The cost depends on the size of the property, the system you choose, access, and the condition of the existing walls, which is why we quote from a site survey rather than a standard price list. No two houses are the same, so no two quotes should be either.
It’s also worth thinking about what you get back: better kerb appeal, less maintenance, and – with External Wall Insulation – lower heating bills. It’s one of the few home improvements that earns its keep.
Myth #9: Render doesn’t need any maintenance
Modern render is low maintenance. It’s not no maintenance.
Keep the gutters clear, give the surface an occasional clean, and check now and then for signs of damage. That’s about it, but doing those small things can add years to the life of your render and save you from bigger repair bills down the line. Ten minutes a season beats a costly fix later.
Myth #10: All render is the same
Not even close. Silicone, acrylic, monocouche, traditional sand and cement – each has its own strengths, quirks and ideal uses. Some are more flexible, some more breathable, some need more looking after than others.
The right system depends on your property, your budget and the finish you want. That’s exactly why it’s worth getting proper advice before any work starts, rather than picking a render because it worked on someone else’s house.
Thinking about rendering your home?
Most rendering myths come down to old materials or bad installation, not modern rendering itself. The right system, fitted by people who know what they’re doing, will improve how your home looks, protect it from the Manchester weather, and can even cut your energy bills.
If you’re weighing it up and want a straight answer about what would suit your property, we’re always happy to talk it through and provide a free, no-obligation quote.
Frequently Asked Questions
Most properties can be rendered. The right system depends on the construction, the condition of the walls, and the finish you’re after.
Render doesn’t cause or cure damp on its own. Installed correctly, with the right system and proper ventilation, it protects the property from the weather while letting the building breathe as it should.
High-quality render should last decades, with a professional installation and basic upkeep. The exact lifespan depends on the product, the quality of the installation and how it’s looked after.
Often, yes. Minor damage can usually be patched, though the right approach depends on the render type and the extent of the damage. A quick assessment will tell you whether a local repair will do or something more is needed.
There’s no single answer, as it depends on your property’s age, construction, your budget and the finish you want. That’s why we’ll visit your property first, before we recommend what’s best.
