The Roofing Report: A Simple Roof Overcladding Guide
You may have heard the term Roof Overcladding and wondered, what exactly is it?
This month’s Roofing Report it’s our attempt at a straightforward roof overcladding guide to what roof overcladding is, and why it’s carried out so often across Scotland and the UK.
The Basics of our Roof Overcladding Guide
A roof overclad is exactly what it sounds like — a new roof installed over your existing one.
Here’s how it works:
A proprietary bar system is fixed down through the old roof sheets into the structural purlins.
Insulation is rolled out between the old and new roof. This improves thermal performance and helps control moisture.
New roof sheets are installed into the bar system, sealed with mastic and finished with external flashings to keep the rain out long-term.
Background on Your Roof
Like most things in life, roofs don’t last forever. They take a beating from the good old Scottish and British weather — wind, rain, UV from the sun, frost, and snow. Eventually, they reach the end of their service life.
Why Choose Roof Overcladding?
When leaks keep coming back no matter how many repairs you try, roof overcladding can be a cost-effective, long-term solution. Done properly, it will last for between 20–40 years.
If you’ve got sensitive operations or a production line under your roof, overcladding is often the best — and sometimes the only — realistic option.
The Alternative: Full Roof Replacement
The main alternative is removing the old roof completely and starting fresh.
While roof replacement this can offer extra benefits, it usually costs 20–25% more than overcladding. In terms of waterproofing, both options achieve the same end goal: a watertight roof.
So why replace instead of overclad? Here are the main reasons:
Appearance: Overcladding keeps the same layout. Replacement gives you a totally new internal aesthetic.
Thermal Performance: It’s easier to hit specific U-values with a replacement, as the old roof is gone. Older buildings often aren’t airtight, which can limit overcladding’s performance.
Natural Light: Overcladding usually follows the existing roof layout. If you want to redesign skylight positions, replacement is the better option.
Hazardous Materials: Many roofs from the 60s–80s used asbestos cement sheets. Replacement removes these hazards completely.
Our Overcladding Experience
Industrial Roofing Scotland have been in the roofing and cladding industry for more than a decade. We’ve seen excellent overcladding projects — and some not so good ones. From experience, these three steps make a huge difference:
Engineering Checks – Always have an engineer or expert check the proposed installation. I’ve heard of entire roofs blowing off due to poor planning. This is avoidable with proper checks.
Manufacturer Guidelines – Follow them to the letter. Warranties only hold if the installation is done correctly. In most cases I’ve seen, failures come down to installers cutting corners.
Accountability – After installation, have an expert confirm it meets the manufacturer’s standards. Ask for warranties and a detailed work schedule. If a contractor can’t provide this documentation, don’t hand them your money. Reputable firms will always back their work with paperwork.
In a Nutshell
If your industrial roof has reached the end of its life, roof overcladding is often the most cost-effective, low-disruption upgrade. It gives you:
✅ A watertight new skin
✅ Better insulation
✅ Extended service life
Less waste going to landfill
That said, if your roof contains asbestos cement, removal and replacement is the safer choice.
The key is to do your homework: get a structural survey, follow manufacturer guidelines, meet building regs, and choose the right materials. And if you’re unsure, speak to a professional — or reach out to Industrial Roofing Scotland. If we don’t have the answer, we will know someone who does.
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