How to stop leaks - bob the Roofer

Well - I should say preventing roof leaks.

It’s better to prevent a leak than to realise you have a leak in the middle of a downpour at 2am and then try to stop it. If you notice a stain on the ceiling or have rain water dripping through a hole means that it has probably been happening for some time and could potentially cause costly damage to the plaster or timberwork.

In this busy demanding world most people don’t suddenly decide to go up and check their roof unless it is leaking. Oops! Too late!

Here are some tips you may find helpful.

One of the first and easiest ways to prevent leaks is make sure you keep the leaf debris off the roof, especially if you live

on the beautiful leafy North Shore of Sydney where I do so much of my work.

Simply put, water has to flow. If leaves are creating a dam the water still has to flow somewhere.

Ridge capping mortar. This is a big one.

Check for cracks in the pointing or any missing mortar (great for possum entry too).

Along the horizontal ridgeline any cracks in the mortar can allow water ingress that builds up between the back of the tile

and the bedding.

The practice of inserting “weep holes” in the mortar before it sets allows water to drain away before it can build up. Sometimes weep holes have been forgotten or they just didn’t bother to put them in.Sometimes new pointing has been applied over the existing weep holes and just creates a new leak. The old mortar we used long ago did its job for the time but times have changed.

Today we use polymer technology or flexible pointing, to repoint ridge capping and it’s even pre-coloured to match your roof tiles. Although it is flexible and is designed to move with the roof unlike straight sand/cement, it can still develop cracks.

Rust in flashings. This is not always easy to see and you may have to lift some tiles or unscrew some roof sheeting to find it. Even a pin hole can let an enormous amount of water through over a period of consistent rain.

Design Faults. I often get calls to problems that have been ongoing and so many others have attempted to fix (usually silicone or bitumen over everything they can see that has an opening). If the roof is faulty to start with, ie, corners were cut, pitch was compromised to allow legal ceiling height, etc, there’s not really anything can be done except pull down and start again. Sorry, I probably can’t operate but talk to me anyway.

Typical tile roof problems. Terra cotta. Some earlier terra cotta roof tiles were made with poor firing techniques making them weak and brittle that can break with the slightest pressure. Roofs around the Sydney Inner West where I'm also in demand are notorious for what we call “doughie tiles”.

My advice would be don’t get on your roof and don’t let anyone else on your roof unless they know what there doing.

Terra cotta tiles can also “fret” which means the clay turns to powder or flakes away in small pieces usually under the overlapping parts of the tile although I have seen fretting right in the middle of the tile with a hole as big as a ten cent piece.

Broken tiles should be fairly obvious but sometimes you may have to pull a few out around the leaking area and work back towards the leak.

Pipes, chimneys and other protusions. These are common causes of leaks because the flashing is sometimes concealed under the tiles. Lead flashing can develop fractures that open up and of course leaf build up is again a problem that can’t be seen without dismantling the roof.

When I go out to check a leaking roof I am often asked why it hasn’t leaked before, especially if the home owner has lived there for some time. ( It’s a bit like driving a car for 20 years, never servicing it and when it breaks down asking how come it’s never broken down before).

All the above listed leaks or potential leaks are problems waiting to happen unless a tree branch or something has gone through the roof it’s usually just a matter of time before a roof will leak. Call Bob: 0418 677 188 or email: bob@bobtheroofer.com.au