At a glance
- Best time: September to early November, before heavy rain and while roofs are dry
- Flat concrete roofs with no or tired membrane are the main cause of winter leaks
- Common options: liquid membrane, bitumen sheets, or insulated systems
- Fix the falls, drains and parapet joints first, or the new membrane won't last
- In a block, the roof is usually a common part, so agree works with the other owners
Why Maltese roofs leak
Most homes in Malta have flat concrete roofs covered with a screed (xorok or concrete). Over years of sun and heat the surface cracks, joints open up around parapets and water tanks, and drains block with dust and leaves. The first heavy rain of autumn finds every gap.
Water that gets into the slab doesn't just drip from the ceiling. It rusts the steel in the concrete, which expands and cracks it (concrete cancer), and it feeds damp and mould inside. A roof repair is cheap compared with fixing that later.
Signs your roof needs work
- Stains, bubbling paint or mould on the top-floor ceiling
- Cracks in the roof surface, or a membrane that's peeling, brittle or blistered
- Puddles that stay on the roof for days after rain
- Cracks where the roof meets the parapet walls, or around tank stands and pipes
- Rust stains or bits of concrete falling from the ceiling or balcony soffits
Your options
- Liquid membrane (acrylic, polyurethane or hybrid): painted on in coats, with reinforcement mesh at the joints. Good for roofs with lots of corners and fittings.
- Bitumen (torch-on) sheets: a proven, hard-wearing option for bigger flat roofs. Usually finished with a reflective coat to keep the roof cooler.
- Insulated roof systems: insulation boards under the waterproofing. They cost more but make the top floor cooler in summer and warmer in winter, and can improve your EPC rating.
Whatever the membrane, the preparation matters most: clean the roof, repair cracks, correct the falls so water runs to the drains, and seal the parapet joints properly.
When to do it
The best window is September to early November, when roofs are dry and before the heavy rain starts. Membranes need dry weather to cure. Leave it until December and you'll be chasing dry days.
Roofs in apartment blocks
In most blocks, the roof belongs to all the owners as a common part, unless your contract says the airspace or roof is yours. Repairs are usually agreed and shared through the block administrator. If the leak is coming into your flat, put it in writing to the administrator early.
If works on a neighbouring site damaged your roof, see our guide to the BCA damage compensation service.
How we help
We inspect the roof, find the real cause of the leak, and give you an itemised price for the repair and membrane. Then we manage the works so they're done before the rain, with photos of each stage.
This guide is general information. A perit should check any roof showing structural damage such as exposed or rusting steel.
Frequently asked questions
When is the best time to waterproof a roof in Malta?
September to early November, while roofs are dry and before the heavy winter rains. Membranes need dry weather to cure properly.
How long does roof waterproofing last?
It depends on the system and the preparation. A well-installed membrane on a properly prepared roof lasts many years; a membrane laid over cracks and poor falls can fail within a season.
Who pays for the roof in an apartment block?
Usually all the owners share the cost through the block administrator, because the roof is a common part, unless your contract says otherwise.
