WHAT IS ROOF CROCODILING AND HOW DOES IT AFFECT YOUR FLAT ROOF?
Waterproofed concrete and composite flat roofs on residential and commercial buildings require more maintenance than sloped roofs. They react differently to sun and moisture than tiled or sheeted roofs and require more frequent maintenance to ensure they function as they should. One common problem with many flat roofs is crocodiling.
What is Crocodiling?
Crocodiling is a crazed cracking pattern on the surface of the waterproofing. It looks like crocodile skin, which is where the name comes from.
Crocodiling is a sign that your waterproofing is ageing. The sun’s UV rays dry out and damage the waterproofed surface, and after five years or more years, the coating may develop small cracks. The older your roof gets before you repair the crocodiling, the more expensive it will get.
Extreme temperature changes, changing from hot sunshine to sudden cloudbursts and rain, and even hot winter days and very cold nighttime temperatures will cause new cracks to appear and will make existing cracks worse.
Leaves and debris will allow water to pool on the membrane which, together with the elements, will hasten the deterioration of the protective coating and waterproofing itself.
Any structure requires ongoing roof inspection and roof maintenance to prevent leaks. By identifying minor problems you can save yourself major repair costs in future. You can thereby also extend the lifespan of your roof considerably before needing to replace it.
Types of Roofs
Together with walls and windows, roofs are a primary component which protects the interior of the building.
There are two main types of roof systems: low-slope (flat) and steep-slope roofs.
Most multi-unit residential buildings use low-slope roofing, while townhouse buildings and single detached houses generally use steep-slope roofing.
Both roof types may be used in some buildings.
Low-slope roofs have a waterproof membrane and a series of drains that remove water from the roof surface. As they are low-slope, these roofs must be water-tight to function properly.
The roofing membrane is applied as;
A liquid that cures or dries to form a waterproof surface,
Or fabricated from pre-manufactured sheets, joined together to create a surface, impermeable to water.
These membranes seal all openings and penetrations through the roof to prevent water leaks. With frequent roof inspections and maintenance, the membranes can provide a leak-proof for up to 20 years.
Steep-slope roofs have overlapping roofing materials to create a surface that, together with gravity, sheds water effectively. The roofing materials include:
asphalt or fibreglass shingles,
and asbestos/fibre or metal sheeting.
Why roof maintenance?
Reduce the likelihood of premature leaks and ageing by regularly inspecting your roof, and doing maintenance work where necessary. Sunlight, rain, hail, wind and temperature changes gradually break down the roofing materials. Eventually, the roof will need to be replaced. However, proper maintenance and care will maximize the service life of the roof.
Roofing systems generally have an anticipated “leak-free life”. The roof should not leak over this time span if properly designed, constructed and maintained. After this time the roof system may still continue to provide many years of service. Leaks will, however, occur eventually. These may increase up to a point when the entire roof will need to be replaced.
After a severe windstorm, or extreme weather, inspect your roof for damage.
Proper roof maintenance reduces costly premature damage. Undetected leaks can damage the building’s structure and interior finishes.
Roof inspection, maintenance and repairs
All roofs require regular inspection. Because of safety issues, a professional home inspector or professional roof inspector should be employed for this purpose. A professional inspector has specialist knowledge, uses the proper equipment and meets all safety requirements. You, your body corporate or maintenance manager should coordinate this work.
A possible roof problem can be identified by damage to the ceilings or walls of the home. If you are renting or living in a complex, notify your body corporate or maintenance manager.
The qualified professional inspecting the roof should
be familiar with the roofing system in your building,
be able to identify potential problems, and
know how to take the necessary safety precautions while doing an inspection or maintenance work.
Specific items for roof inspection and maintenance will depend on the type of roof(s) on your building. You will find a checklist of common roof maintenance items at the end of this article.
Inspect twice a year;
in the autumn or spring to address any possible summer or winter damage, and
In the spring or autumn to prepare for the upcoming summer or winter rain.
After any storm, high winds, extreme rain or hail, inspect your roof, including flashings and other accessories. If construction has taken place on the roof, check for leaks.
The roof inspection should include the underside of the roof structure and the outside of the building. These areas may show up potential problems with your roof.
Who does the roof inspection?
Hire an InterNACHI certified home inspector to inspect and review the condition of the roof.
A professional roof contractor should carry out any required roof maintenance. The professional will have the necessary tools and knowledge to repair identified the problems. Skylights and other roof penetrations may require specialized attention. A specialist supplier or manufacturer may need to be employed.
Weathering reduces the expected service life of the roof. Furthermore, it also affects the appearance of the roof. A yellow or brown stain on the ceiling could be an indication that moisture is leaking from the roof.
Roof leaks can result from overflowing gutters or backed-up downpipes. Debris in gutters and downpipes can prevent proper water drainage. Moreover, this may also result in water backing up and overflowing into adjacent building walls and moisture damage to the roof structure.
This makes periodic roof inspections essential!
I will do a RoofInspection and Report which will identify problems with your roof. The report will include the condition of the roofing products, materials and flashings. Furthermore, the report will also include any other roof maintenance issues.