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When it comes to homes and commercial buildings, waterproofing is a critical element for protecting the building and preserving its value. Poor waterproofing can fail, leading to cracks, mould issues, and structural defects like concrete cancers. Failure of your waterproofing can cause safety issues, significantly reduce the value of your property, and lead to unfitness for occupation. Fortunately, if you catch waterproofing issues earlier rather than later, you could remedy the problem so it’s as good as new.

What happens when waterproofing fails

Waterproofing might account for just  2-3% of a building’s total costs, but waterproofing defects can end up causes 80% of a building’s defects. When waterproofing fails, the implications are significant.

  • Safety – Structural damage can be severe to the extent the building is no longer safe. This can lead to liability and insurance issues for landlords.
  • Uninhabitable – Waterproofing failures can lead to concrete cancer, mould, and serious structural issues that make a home, office, or other site uninhabitable. This can mean loss of rental income and major repair costs.
  • Leaks – Leaking water can damage furniture, carpeting, and other items in addition to the building’s structure.
  • Concrete cancer – Concrete in buildings are typically reinforced with steel bars or mesh, and exposure to air and water can lead to corrosion of the steel. The steel then expands, which results in spalling, or the surrounding concrete cracking. The steel is now further exposed to the elements, and the level of corrosion accelerates. This concrete cancer is a common outcome of severe waterproofing failure.

Common causes of waterproofing failure

Waterproofing failure has different potential causes, but poor workmanship and the use of a membrane that is not fit for the purpose or is not part of an entire system are the leading causes.

1. Issues from higher levels

In multilevel buildings, the higher floors can cause issues when it comes to waterproofing failure. Top-floor levels can experience waterproofing problems from rainwater puddles forming on the roof. Flat roofs, in particular, can collect excessive rain that leads to leaks and eventually damage the structure of the building. Poor workmanship on higher levels, such as defective plumbing, can also lead to waterproofing failure.

2. Poor waterproofing work

Poor workmanship, including incorrect installation methodology, can lead to leakage issues due to waterproofing failure. Tricky places like balconies and windows need professional work when applying waterproofing. Poor workmanship also includes wrong product specifications, when the wrong product is used; and insufficient substrate preparation, which means poor preparation before the waterproofing membrane is applied.

3. Lack of maintenance

Ongoing maintenance in the form of checks and remedial waterproofing enables you to catch problems early and avoid significant issues like concrete cancer. Even tiny leaks and cracks should be dealt with right away as water damage can escalate quicker than expected, leading to major problems. Maintaining existing seals on your windows, doors, and wall systems is also recommended. Checking balconies, roofs, windows, cracks, and leaks as soon as you become aware of them and taking a proactive approach to maintenance minimises the risk that it develops into a major problem.

4. Wrong choice of waterproofing membrane

Make sure to choose a complete waterproofing system that includes a sheet membrane with all the ancillaries. It is also important to consider how flexible the membrane is to allow building movements and how resistant it is to the UV, chemicals, harsh salt air and in the case of green applications, to root penetrations.

Common waterproofing problems associated with Strata Buildings and how the Wolfin system can help to rectify these situations

Common waterproofing problems encountered in most Strata Buildings are leaks coming from decks, garden beds and failed cavity flashings. Not long ago, the Wolfin waterproofing system was used to rectify these problems in an apartment situated in Darling Point. In this case, the waterproofing was jeopardised by building movement, poor workmanship and the aggressive marine environment in which it’s located. The fact that the old deck membrane and the cavity flashings were not working in conjunction with each other also led to the failure of the waterproofing at this junction.

The Wolfin GWSK membrane was installed to the decks and planter boxes and the cavity flashings were reinstated using the Wolfin IB membrane. 316L Stainless WolfinSteel profiles were also used to terminate the membrane to ensure the longevity of the waterproofing membrane in this coastal environment.

Common problems with flat roofs

The refurbishment of a failed flat roof is the most common waterproofing problem that the building industry is coming across. Taking all the variables into consideration when specifying a waterproofing solution is not an easy process.

Water ingress due to failure of the roof components or due to the shortcomings of the roof construction can have a dramatic effect on the building occupier, resulting in water ingress and the loss of thermal performance of the insulation material (if any insulating is installed). In addition the financial burden associated with the roofing works necessary to reinstate the integrity of the roof waterproofing can be significant.

Diagnosis of the problem may not be straightforward. Water could be collecting within the roofing layers due to several reasons.

  • Poor perimeter detailing/failure at upturn
  • Failure of the outermost weathering layer
  • Inadequate and poor detailing around penetrations

When undertaking a roof refurbishment project, the use of Wolfin products can lower your costs

because you save the expensive component of stripping up and disposing of the old failed membrane. By avoiding construction waste, you can also actively help to preserve the environment.

Refurbishment with Wolfin roofing & waterproofing membranes has been a tried and trusted solution for flat roofs, green roofs and building surfaces. Of all the Thermoplastic roofing & waterproofing membranes on the market, Wolfin offers the highest water vapour diffusion permeability, which allows the trapped moisture in the roof layers to completely dry out.

Click here to read about the 9000 sqm flat area refurbishment completed at The National Library of Australia in Canberra.

Checking if you need remedial waterproofing

Your maintenance checks ideally include a review of the drainage efficiency of roof areas, the plumbing system, and areas like windows that are directly exposed to water and the elements. Remember, a thorough inspection of the building is important for catching cracks and leaks as early as possible. You’ll want to check key areas like roofs, and balconies as well as living and working spaces even if they’re situated well away from sources of water.

Commercial roofs should be inspected at least once every six months, and an inspection should look at the vents, drains, and other areas of the roof where water could seep through to the building. An inspection should look for stains as well as cracks and leaks.

Check your drains, plumbing, and irrigation as part of your regular maintenance. These areas of your building or site are more likely to have leaks that are hard to spot, so do a comprehensive review of these areas on a regular basis. Even the smallest leaks warrant your attention, and with some quick action and remedial waterproofing, you can save money and preserve your building’s value.

Work with professionals for remedial waterproofing

Your best chance of obtaining a great remedial-waterproofing outcome is with waterproofing experts. Avoid trying to fix the issue yourself, and have an experienced waterproofing company to inspect your site and carry out the remedial work.

Waterproofing experts can assist with the right products for the area, and they use the correct methodology to apply the waterproofing membrane.

Waterproofing failure can have a drastic impact on the safety and value of a building. Poor workmanship, including using the wrong product and applying the membrane incorrectly, is often behind waterproofing failure. Regular checks and timely remedial waterproofing, however, can help you stop small leaks and issues turning into major problems.

As Australia’s leading provider of premium waterproofing solutions, Projex has over 25 years of experience in supplying outstanding engineering and waterproofing products. Explore our website for more on our waterproofing solutions. To find out more about how we can help you with remedial waterproofing, contact our friendly team today.

The Projex Mission is to source and supply technically excellent products to meet the needs of owners, designers, insurers and operators of buildings and structures for specialist protection against water, industrial liquids, impact and corrosion risks.