Causes of Leaks in your Roof

The cause of your water leaks often depend on your roofing profile and specification. Metro Roof has put together a brief list of common causes of water leaks that occur in each roofing profile and application.

The list shows that an incorrect installation of a particular roof profile, is often the main cause of a leaking roof.  Therefore ensuring you work with a qualified and professional roofing contractor – who has experience in your roofing specifications – should be your top priority to ensuring a dry and protected home.

Causes of Leaks in your Roof according to Roofing Profiles:

1. Corrugated metal sheeting:

The minimum recommended roof pitch for corrugated is 17 degrees. If the pitch is less than 17 degrees water may enter through the laps of the sheets where the water is pounding. The corrugated sheets must at least lap over each other by 1.5 rolls. The roof screw must be fixed on top of the roll in the centre. The sheets must then be bend up at the top in order to avoid the water from entering underneath the flashing. 

2. Concealed fixed profile metal sheeting:

Concealed fixed profile sheeting is the recommended profile to be used on flat pitched roofs. The metal sheet is installed with a klip system and NOT pierced with a screw. Leaks may occur if the sheets are not bent up at the roof apex and bend down at the gutter end. The roof flashing must cover at least two upstands on the roof sheeting. 

3. Concrete tiles and nutec slates:

1. Leaks may occur if tiles are broken or have slipped down the roof. The roof valleys must be properly sealed with aluminum valley lining and bend up underneath the tiles. It is recommended to use aluminum nails to fix the nutec slates. A waterproofing membrane must be installed underneath the ridge tiles to ensure it is water tight. 

4. Natural slate roofs:

The common leaks on natural slate roofs is due to missing slates, broken slates or when the waterproofing membrane underneath the slate has disintegrated and reached its lifespan. It is recommended to use aluminum nails to fix the slates in order avoid the nails rusting and braking. 

How to avoid leaks for your particular roofing material:

It is very important to have the correct material installed on your roof to avoid possible future leaks. If your property is situated within 5km from the ocean, you must install the Clean Colorbond Ultra AZ200 – as the thicker base metal coating material will ensure that your roof lasts longer. The Clean Colorbond AZ150 material can be installed to properties that are further than 5km away from the ocean. 

Your roof material must be maintained annually so that the metal sheeting can be washed down and cleaned. Gutters must also be cleaned annually.

In areas where your roof meets a parapet wall, the correct flashing must be installed that returns at least 75mm against your wall. The upstand of the metal flashing must be sealed with a waterproofing membrane. The waterproofing membrane must be painted with 3 coats of acrylic waterproofing paint. This will ensure your wall doesn’t leak.

If you have any skylights or chimney flutes penetrating through your roof sheeting, it must be sealed properly to avoid water leaks.

Let us help you with your leaking roof!

The Metro Roof team has been working together on all roof installations and applications for over ten years. Let us ensure your roof is installed, repaired or designed in a way that will guarantee a dry, secure and protected living area.

Call us on 086 101 4653

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There can be numerous reasons why your roof is leaking –  so give us a call and let us assist your specific roofing queries today.

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