Ridge capping repair that holds through the next storm

The ridge caps are the tiles that run along the top of the roof and down every hip. They are not clipped or screwed on. On almost every tile roof in Melbourne they sit on a bed of sand and cement mortar, and that mortar does two jobs at once: it holds the cap in place and it closes the gap between the cap and the tiles underneath.

Bedding is the thick mortar bed the cap sits on. Pointing is the thinner finishing layer worked over the outside of the joint, the part you can see from the street. Bedding gives the cap its grip; pointing seals the edge so wind-driven rain cannot get under it.

Both were once done in the same rigid mortar, and rigid mortar is the reason ridge capping needs repair at all. A roof moves. Tiles expand on a hot afternoon and shrink on a cold night, the timber frame under them flexes in wind, and a mortar joint that cannot move simply cracks. Once the pointing cracks, water gets into the bedding, the bedding softens and crumbles, and the cap starts to lift. That is when you find grey mortar crumbs in the gutter and, sooner or later, a cap on the lawn after a storm.

Ridge capping repair is the job of renewing whichever of those two layers has failed, and doing it in a way that does not fail the same way again.

The first thing our crew does on the roof is test the caps by hand. A cap that is firm with cracked or missing pointing needs repointing: the old pointing is raked out, the joint is cleaned, and a new flexible pointing bead is worked in over the sound bedding. A cap that rocks, has slid, or is sitting on bedding you can crumble between your fingers needs rebedding: the cap comes off, the old mortar is removed down to the tiles, a fresh bed is laid, the cap is re-laid straight and to line, and then it is pointed.

How much of the ridge is redone depends on what the test finds, not on a fixed rule. A single storm-lifted cap on a hip end can be rebedded on its own. A run of caps with cracked pointing on the sunny side of the roof is usually repointed along that whole run, because the pointing beside the crack is the same age and will follow. When the bedding is soft along most of the ridge, the honest answer is a full rebed and repoint of every ridge and hip, and we will say so before we start rather than patch it and come back next winter.

The photos decide it, not the sales pitch. You get pictures of the caps before they are touched, and again once they are bedded, pointed and dressed off, so you can see for yourself which caps were re-laid and which were sealed.

Flexible pointing is a polymer-modified compound that cures to a firm, slightly rubbery finish instead of a brittle one. It bonds to the cap and to the tile, and it stretches a little as the roof heats, cools and flexes, which is exactly what rigid mortar pointing could not do. It has been the standard finish on tile-roof ridge work for years now, and it is the only pointing we apply.

It comes in a range of colours, so a new bead on a terracotta roof is matched to terracotta and a bead on a charcoal concrete roof is matched to charcoal. On a roof that has been painted or coated, we match the coating colour, so the repointed ridge does not read as a stripe from the street.

Flexible pointing does not replace bedding. It is a sealing layer, and it needs a firm bed under it to do its job. Squeezing new flexible pointing over crumbling bedding is a common shortcut that looks fine for a season and then lets go, because the cap underneath was never secured. Our crews rebed first wherever the bedding has failed, then point.

If you want the longer explanation of how bedding, pointing and the modern compounds fit together, our roof repointing and rebedding guide covers it in detail. This page is where you book the work.

Most ridge work in Melbourne is on concrete tile roofs across the brick veneer estates built from the 1970s through the 1990s, where the original bedding is now decades old and the pointing has often been patched more than once. Terracotta roofs in the older suburbs are the other big group; terracotta caps are often worth keeping and re-laying rather than replacing, and we do that where the caps are sound. On both, the hips take the worst of the wind and are usually the first to fail.

While the crew is on the ridge they also check the things that fail alongside it: cracked tiles along the ridge line, the valleys where two roof planes meet, and the flashings at walls and penetrations. Metal work like valleys and flashings is carried out by licensed roof plumbers, and if something needs attention up there you are told, with a photo, and quoted separately. Nothing gets added to the job without your say-so.

Ridge capping repair is a repair, not a restoration. It does not include cleaning, sealing or painting the roof, and it does not include re-roofing. If the whole roof is tired, we will say so honestly and point you to the right service instead of dressing up a repoint as something bigger.