Why Is My Roof Leaking? The Most Common Causes

Ridge and hip capping, by a long way the most common

The mortar holding your ridge caps down was almost certainly a rigid sand and cement mix. On anything built before the late nineties it definitely was. That material shrinks as it cures, keeps shrinking for years and eventually cracks right along the join.

Water does not pour through the crack. It gets driven into it sideways by wind, which is why this particular leak has a signature: it only happens when rain arrives on a strong westerly and it stays perfectly dry through a week of gentle drizzle. Homeowners often describe it as random. It is the opposite of random.

Look in your Gutter Replacement Perth after a windy fortnight. Grey crumbs and grit sitting in the bottom are pointing mortar that has already let go.

Flashings at walls, chimneys and skylights

Anywhere the roof meets something vertical, there is a Roof Plumbing Perth doing the waterproofing. Two storey walls, chimneys, parapets, skylight surrounds and the junction where a patio roof joins the house all rely on one.

Roof Plumbing Perth fail through movement rather than corrosion. Houses settle, timber shrinks and the sealant behind the flashing perishes after fifteen or twenty summers. The gap that opens is often invisible from ground level while being perfectly adequate to admit water.

Blocked gutters and dammed valleys

This one frustrates people because the roof itself is completely sound. Leaf litter fills a gutter or packs into a valley, water backs up behind the obstruction, rises above the edge of the tiles and runs underneath them into the roof space.

It is a maintenance problem wearing the costume of a structural one. Clearing gutters twice a year prevents most of it. Under heavy tree cover, more often.

What we do about it

We inspect the roof and, where the manhole allows, the underside. We photograph what we find. Then you get a written price for repairing the cause rather than dressing the symptom.

Sometimes that is a single afternoon of work. Occasionally it is a bigger conversation. Either way you will be told which one it is before any money changes hands.

What Perth weather does to the odds

Our leaks are seasonal in a way that confuses people. Summer does the damage. Winter reveals it.

Months of intense ultraviolet exposure dry out mortar, perish sealants and bake the flexibility out of anything rubber or bituminous. Nothing leaks, because nothing is falling on it. Then the first serious cold front arrives off the Indian Ocean, throwing rain almost horizontally at the western face of the house and every gap that opened during summer gets tested at once.

That is why so many people ring in June about a roof that was completely fine in March. The fault was already there. It simply had no water to find it.

Common questions

Can I wait until summer? Waiting costs money. Wet insulation stops working, plasterboard degrades and timber that stays damp through a whole winter invites decay. A repair booked in May is cheaper than the consequences dealt with in November.

Does one leak mean the whole roof is failing? Rarely. Most Perth roofs we attend need one component addressed. Tiles themselves are extremely durable and a fifty year old concrete tile is often in better shape than the mortar and metalwork around it.

Will my landlord or strata handle it? For rentals, report it in writing immediately and keep the record. In apartments and townhouses the roof is usually common property, which makes it the owners corporation's responsibility rather than yours.

Which suburbs do you cover? The whole metropolitan area, from Yanchep and Two Rocks in the north through Mundaring and Kalamunda in the east down to Rockingham, Baldivis and Mandurah.We attend leak calls across the northern corridor through Joondalup, Currambine, Butler, Alkimos, Quinns Rocks and Burns Beach and just as often through the older eastern suburbs around Bassendean, Guildford, Midvale and Swan View. Different housing, different faults, same investigation.