A Guide to Slate Roof Repairs, Restoration and Re Roofing

Slate roofs are one of Sydney’s heritage landmarks and there are more slate roofs in Sydney than other state in Australia.
You see them across the terraces of Paddington and Balmain, on cottages in Glebe, and adorning council buildings, universities, schools and churches that shape the city’s older neighbourhoods.
Built to last, many of these roofs have already stood for over a century. And with the right care, they can last for another.

If your roof was built from slate, it deserves more than a quick patch or cosmetic fix. This is about doing the work with respect for the home, the materials, and the story behind them.

Why Sydney Has So Many Slate Roofs

Slate arrived in Sydney along with the people who knew how to lay it.
Welsh slates (mainly from Penrhyn and Cwt-y-Bugail) were shipped to Australia in the 1800s and used to roof everything from terrace rows to civic buildings.
It made sense to use slate as it was strong, natural, and fireproof.
It looked right against sandstone and brick. It suited the climate. And when laid well, it lasted.

Today, many of those original roofs still remain. Even on homes where sections have been replaced or patched over, you can often see the outline of the original work.
Keeping these roofs is part of appreciating the skill of those original tradesmen and their workmanship and intricate details gives so much architectural character to Sydney homes.

How Long a Slate Roof Should Last

When installed properly, a natural slate roof can last over 100 years. In some cases, 150 or more. The slate itself doesn’t wear out.
What usually fails first are the components around it—nails, flashing, valleys, mortar and battens. When these parts give way, tiles can slip, water can get in, and more serious damage can follow.

That’s why slate roof care is rarely about replacing everything. Often, it’s about preserving the parts that still work, and fixing the areas that don’t.
Read more: How Long Does a Slate Roof Really Last?

Common Problems and What to Look For

Some slate roofs show their wear clearly. Others, it is not obvious until there’s a leak or stain on the ceiling.

Here are the signs that something might be wrong:

• Slipped, cracked or missing tiles
• Water marks or damp in ceiling corners
• Mortar breaking down on ridge capping
• Rusted or loose flashing near chimneys and valleys
• Sagging or uneven roof lines
• Moss or lichen buildup, especially in shaded areas

Some of these issues can be handled with simple repairs. Others might point to deeper problems with the underlay or roof structure. A proper inspection by a roofer who knows slate is the best way to find out.
Read more: How to Tell When Your Slate Roof Needs Repair

What Real Slate Roof Restoration Looks Like

Restoring a slate roof does not mean spraying it with paint or covering it in a sealant. In fact, that kind of surface restoration can do more harm than good.

A proper restoration includes:

• Cleaning the slate carefully, without pressure damage
• Removing and replacing cracked or failing tiles
• Repairing or repointing ridge capping and mortar
• Checking and replacing flashing with lead (Occasionally copper is used)
• Reinforcing the structure where needed without altering appearance
• Using reclaimed slate to match existing colours and textures

This brings the roof back to working condition while keeping its original look and feel intact.
Read more: What Happens During a Real Slate Roof Restoration?

Repair or Re Roof? Knowing the Right Time

Not all roofs need to be pulled apart. If the slate is sound and the structure underneath is healthy, many roofs can be repaired and maintained for decades to come. But if the battens have rotted, the underlay is gone, or the nails are failing across wide sections, a re roof may be the better path.

A re roof involves removing the old tiles, replacing the battens and sarking, and reinstalling slate often reusing as much of the original slate as possible.
Where needed, matching new or reclaimed slate is sourced to complete the job seamlessly.
Read more: Repair vs Re Roof: Making the Right Call for Your Home

Using Reclaimed Slate

One of the most effective ways to preserve the character of a slate roof and reduce costs is by using reclaimed slate. These tiles have often come from older buildings and can be matched in tone, size and weathering. When used properly, they blend with the original roof so that new work is almost invisible.
Read more: Using Reclaimed Slate

Heritage Roofing and Council Requirements

If your roof is in a heritage zone, you may need to follow strict rules for repairs or restoration. We know how to work within these guidelines while still making the roof watertight.

Reclaimed slate also helps maintain heritage integrity, which is especially important in conservation areas or homes subject to local heritage controls.
Read more: Slate Roofs and Heritage Requirements in Sydney

Leadwork and Flashing: The Unsung Heroes

The tiles may catch the eye, but it’s the leadwork that keeps everything sealed. Roofs with chimneys, valleys, skylights or parapets all rely on correct flashing to direct water away. Over time, this flashing can crack, lift or corrode, allowing moisture to get behind the tiles.

Traditional lead flashing not only lasts a long time but it also fits the visual language of a heritage roof. Replacing damaged flashing is often the first step in stopping a leak, and one of the most important parts of any repair or restoration job.
Read more: Why Leadwork Matters and How to Know When It’s Failing

What It’s Like to Work with Us

We are a small team who do the work ourselves. When you call us, you speak to someone who knows slate, knows Sydney, and has spent decades working on homes just like yours.

We understand that every job is different. Some clients want to maintain their home’s history as faithfully as possible.
Others need practical repairs that will keep the roof sound for another 20 years.
We’ll give you honest advice and talk you through what makes the most sense for your roof, your home and your budget.

Frequently Asked Questions

• Can I match my old slate if some tiles are broken?
• What is the difference between repairing and restoring a roof?
• How long will a re roof take?
• Will I need council approval for heritage work?
• What is the cost difference between slate and other roofing options?

We are currently adding articles that answer these questions.

Start with a Proper Roof Inspection

If you’re not sure what condition your slate roof is in, we can help. Our inspections are carried out by us and you’ll get a clear explanation of what we find, what it means, and what we recommend.

Call Slate Roof Restorations today to talk to the people who will actually be on your roof.