Tiled Roof Waterproofing Tips
If you’ve ever noticed damp patches on your ceiling or water dripping during heavy rain, chances are your tiled roof needs attention. Tiled roofs are beautiful and durable — but only if they’re properly waterproofed. I’ve helped hundreds of Johannesburg homeowners with leaks caused by cracked cement joints, worn ridge caps, or old underlays, and in most cases, the fix was simple once the root cause was clear.
In this post, I’ll share practical tiled roof waterproofing tips that actually work, based on what I’ve seen over 30+ years in the field.
Why Tiled Roofs Start Leaking
Many people think roof tiles alone keep water out — but that’s not true. Tiles mainly protect the underlay and flashing system below. If those fail, water can easily seep through.
Here’s what usually causes tiled roof leaks:
- Cracked or loose ridge tiles
- Damaged or missing underlay
- Blocked valleys or gutters
- Poorly sealed flashings around chimneys and vents
- Broken or shifted roof tiles
Just last month, I worked on a Randpark Ridge home where a few slipped ridge tiles had let water pour straight into the ceiling. The tiles looked fine from the ground, but once we climbed up, we found the cement joints had crumbled completely.
Check and Repair Flashings Regularly
Flashing — the metal or waterproof layer around roof joints — is one of the most common leak points. If it cracks, lifts, or rusts, water will find its way in.
We often repair flashings using durable sealants or install new lead or aluminium flashing for a longer-lasting solution. Properly sealing these joints makes a massive difference in preventing leaks.
Learn more about Roof Flashing Repairs and why maintaining them is crucial for tiled roofs.
Ridge and Hip Tile Maintenance
The cement (or “bedding”) under ridge and hip tiles is another weak spot. Over time, heat and rain cause it to crack and fall apart. Once that happens, water seeps underneath the ridges.
We remove the loose cement, rebed the tiles, and apply waterproof ridge sealing compounds to ensure they stay watertight.
If your ridge lines are cracked or loose, our Tile Resealing and Ridge Repairs Services as designed specifically for this type of issue.
Don’t Forget the Underlay
The underlay (or waterproof membrane) beneath your roof tiles is your main line of defence. Once it ages or tears, it’s only a matter of time before leaks appear.
When we replace old underlays, we use high-quality, UV-resistant materials that handle Johannesburg’s temperature changes better. We also make sure there’s proper overlap between sections to prevent any gaps.
For larger issues where the roof structure needs work, we might recommend a full Roof Restoration — which includes underlay replacement, ridge re-cementing, and waterproofing.
Keep Gutters and Valleys Clear
Leaves and debris block valleys and gutters, causing water to back up and flow under the tiles. During rainy months, this is one of the most common causes of roof leaks I see.
Cleaning your gutters a few times a year can prevent major damage. If you notice rust or broken joints, get them fixed quickly — water that overflows near walls or ceilings can lead to damp problems inside your home.
If you’ve got persistent drainage issues, check our Gutter Repairs and Waterproofing Services to ensure rainwater flows away properly.
Protective Coatings for Longer Life
Once repairs are done, I always recommend applying a protective coating to extend the roof’s lifespan. This helps reflect heat, resist UV damage, and seal micro-cracks in cement joints.
Our Protective Coatings Services add an extra layer of weatherproofing that keeps tiled roofs looking and performing well for years.
Schedule Regular Roof Inspections
Even a small crack can turn into a serious leak if ignored. That’s why I suggest a professional roof inspection at least once a year — ideally before Johannesburg’s summer rains start.
We offer Roof Inspections and Condition Reports to spot early warning signs before they lead to bigger problems.
Final Thoughts
Tiled roofs can last for decades — but only if you stay ahead of maintenance. Simple things like resealing ridge tiles, checking flashings, and keeping gutters clean can save you from costly ceiling or wall repairs later.
If your tiled roof is leaking or showing signs of damage, I offer free call-outs across most of Johannesburg. Send me a message, and I’ll inspect it personally, explain what’s wrong, and recommend the most effective waterproofing solution.