Cracked Ridge Capping: Why Pointing Fails and What to Do
The cement pointing along your ridge caps is one of the most common causes of Leaking Roof Repairs Perth on older tiled roofs. Here's why it cracks, what happens when it does and why flexible Roof Bedding & Pointing Perth fixes it for good.
Fully licensed & accredited — Builders Registration BC105819 · Painters Registration PC102072 · Patent ID AU-A-2020100623
Cracked Roof Bedding & Pointing Perth is the single most common defect on Perth tiled roofs and one of the cheapest to fix properly. It is also the one most often misdiagnosed as needing a whole new roof.
Two words get used interchangeably here and should not be. Roof Bedding & Pointing Perth are different things that fail differently and cost differently.
Bedding versus pointing
Bedding is the mortar bed the capping tile sits on. It is structural. It holds the cap in position and carries its weight.
Pointing is the finishing compound applied over the join between the cap and the bed. It is weatherproofing. Its job is to stop water getting into the bedding underneath.
A quote that says re-point when the bedding has broken up is a quote for the wrong job. A quote that says re-bed when only the pointing has perished is a quote for too much work. Knowing which you need is worth asking about directly.
Why rigid cement was always going to crack
For decades both bedding and pointing were done in sand and cement. It is cheap, it is strong in compression and it was what everyone used.
It also shrinks as it cures, has almost no flexibility and sits on a roof that expands and contracts every single day as the sun tracks across it. Perth's daily temperature swing is substantial. Over twenty or thirty years that movement wins.
The result is hairline cracking along the join, then open cracking, then caps that rock underfoot.
What flexible pointing changed
Modern flexible pointing compounds are designed to move. They stay adhered to both the cap and the bed while accommodating the daily expansion that used to split cement.
They also bond better to an aged tile surface, which matters because you are almost always applying them to a roof that has been up there for decades.
Any re-point done today in sand and cement is a re-point that will fail again in your ownership. It is worth asking a prospective roofer what they intend to use.
Reading your own roof from the ground
Grey grit and crumbs in the Gutter Replacement Perth are pointing that has already gone.
A ridge line that looks slightly uneven, with one or two caps sitting proud of their neighbours, means bedding has failed underneath.
Vegetation growing out of the ridge join is a bad sign. Seeds germinate where mortar has broken down and there is enough trapped moisture to sustain them. Roots then widen the crack.
Daylight visible along the ridge from inside the roof space means water is getting in as well as light.
The leak pattern this creates
Water does not fall into a cracked ridge. It gets blown in. That gives the Leaking Roof Repairs Perth its distinctive behaviour: it appears during storms with wind behind them and disappears entirely in ordinary rain.
Because it enters at the highest point of the roof, it can run a long way along a batten before dropping. Stains from ridge leaks are frequently nowhere near the ridge.
What the repair involves and what it costs
Where only the pointing has perished, the old material is cut out, the joint cleaned and new flexible compound applied. That is the cheaper job.
Where bedding has broken up, caps are lifted, old mortar removed, a fresh bed laid to a true line, caps reset and then pointed. More work, more materials, considerably more time on a large roof.
Either way it is measured in ridge metres rather than roof area, which is why two houses of identical footprint can differ substantially. A complicated hip and Roof Valley Repairs Perth roof has far more capping than a simple gable.
Do the whole roof or just the bad section
If one hip has failed while everything else is sound, we will say so and quote that hip.
But where the entire roof was bedded in the same cement by the same crew in the same week, thirty years ago, doing one section usually means returning for the next one within a couple of years. Access and setup get paid for twice. The maths generally favours doing it once.
Why the coastal suburbs get less time
Salt shortens the life of pointing considerably. Salt laden air is drawn into the porous surface of aged cement and every wetting and drying cycle drives crystals further in. Those crystals expand. The mortar breaks down from within.
Mortar that might give thirty years in an inland suburb can be visibly perished at twenty within sight of the ocean. It is not that coastal roofers are worse. The environment simply eats the material faster.
The same applies with different chemistry near heavy industry, where the atmosphere is doing similar work.
Ridge tiles are not all the same
Capping comes in profiles that match the tiles beneath. Barrel, angled and decorative patterns all exist and on older terracotta roofs some of them have not been manufactured for half a century.
That matters when caps need replacing rather than re-bedding. Salvage yards carry reclaimed capping precisely because of this and a matched reclaimed cap is invisible where a modern substitute would announce itself from the street.
On a heritage roof the ridge line is an architectural feature. Treating it as a waterproofing detail alone produces work that is technically sound and visually wrong.
Doing it alongside other work
If a restoration is on the horizon, ridge work belongs inside it rather than before or after. Coating a roof and then re-bedding means disturbing new coating. Re-bedding after coating means patching it.
The sensible order is repairs, then bedding and pointing, then cleaning and coating. Any quote that puts them in a different sequence is worth questioning.
For a straight answer on what your ridge line actually needs, ring 0421 768 842. We photograph the capping, show you what we found and quote the specific work rather than a rate per square metre.
Common questions
How long does re-pointing take? Most single storey Perth homes are a one or two day job depending on total ridge metreage. A complex roof through Applecross or Mount Lawley with multiple hips takes longer than a simple rectangle in Balga.
Can it be done in winter? Repairs, yes, between fronts. Flexible pointing needs a dry surface and a dry window to cure, so we watch the forecast rather than the calendar.
Is flexible pointing more expensive? Marginally, in materials. Considerably cheaper across twenty years, because it does not crack and need doing again.
What if only one section has failed? Then we quote that section. Where the whole roof was bedded at once decades ago the rest is rarely far behind and we will tell you that honestly so you can decide. Ring 0421 768 842 for an inspection.Ridge work fills our calendar through the established middle suburbs. Stirling, Karrinyup, Innaloo, Gwelup, Yokine and Nollamara were built within a decade of each other, so their mortar is finishing within a decade of each other too.
One last practical note. Ridge mortar failing is gradual rather than sudden, which gives you the luxury of planning. Book it for spring or autumn, get the whole run done at once and specify flexible compound in writing on the quote. Those three decisions between them determine whether you revisit this in fifteen years or in five.
Dulux AcraTex accredited applicators
Powerdrive Roofing is an accredited applicator for the Dulux AcraTex roof restoration system, so your coating carries the manufacturer’s product warranty alongside our own 10-year workmanship warranty. How the Dulux AcraTex warranty works →
What Perth homeowners say
There are 206 reviews on our Google listing. Photographs of finished work sit alongside them, which is more useful than anything we could write here.
Materials, warranties and matching
Materials matter more than most quotes admit. We match discontinued tile profiles through salvage stock at Roof Top Industries rather than putting a modern profile across an older elevation, and current ranges come from Bristile Roofing, Perth founded in 1929, or Monier. Coatings are the Dulux AcraTex roof restoration system, applied under accreditation so the manufacturer warranty stands.
Need your roof sorted? Let's talk.
Tell us about your roof and the problem, we'll tell you the likely cause and what it'll take to fix.