28 Apr Concrete stumps or stilts repair
Waterstop Solutions was engaged to inspect and repair 25 concrete stumps/stilts and a concrete slab entrance identified by the client as displaying signs of efflorescence.
Based on our examination only 12 of the 25 stumps and a section of the concrete slab showed evidence of pitting in the concrete. The affected stumps displaying signs of efflorescence caused by rising damp are in direct contact with bare soil underneath the building.
The damage to the concrete stumps by efflorescence appeared to be in the early to mid-stage with only two small sections of unsound concrete observed. When treated early, the risk of developing concrete spalling may be largely mitigated.
To treat the concrete stumps, we recommend the following:
- Perform concrete repairs to the two sections identified.
- Water-blast the concrete stumps and the concrete slab entrance to remove the efflorescence and prime the concrete for the application of a silicate-based, hardener densifier.
- Apply a silicate-based, hardener densifier to the concrete stumps and the concrete slab section to seal the concrete, reduce water permeability and to prevent water from travelling to the surface from within.
- Return after the hardener-densifier has finished chemically reacting with the concrete (a period of 30 days or more), to water-blast clean the concrete stumps and apply render coating to the stumps to improve the coverage of the steel reinforcements and the appearance of the stumps.
During the curing period, we recommend to wet down the concrete stumps every 2 days over the following week while the silicate-based, hardener densifier is chemically reacting with the concrete.
Is efflorescence just a cosmetic problem or could it pose a structural threat?
Efflorescence is caused when carrier moisture brings salts and other minerals to the surface of porous building materials such as concrete, bricks and mortars. The ground in which these materials can come into contact also contains salts and unsealed building materials that are in contact with the ground may be susceptible to efflorescence because they can absorb or wick water through capillary action. When the carrier moisture evaporates, the salts and minerals crystallise creating a build-up of efflorescence (free lime/calcium deposits) that appears as white/light grey/yellow staining or chalky powder on the surface. Sometimes it can mould and efflorescence can be confused by the untrained eye. Efflorescence will turn into powder if pinched between the fingers and it dissolves in water, while mould will not.
Efflorescence alone can be just an aesthetic problem. However, when efflorescence happens, it can be a symptom of moisture intrusion that potentially can lead to mould growth and/or structural damage if left untreated. The capillary action continues as water is drawn to the salts deposited on the surface. The water is attracted by the increasing salt concentration and creates a pressure that can exceed the tensile strength within the porous building material, such as the concrete stumps/stilts in this case, which can result in damage called pitting or spalling.
You may also be interested in the following topics:
If you have any issues with water ingress, rooftop leaks, leaking balcony, leaking basement, cracking concrete slabs, structural cracks, concrete deterioration, spalling concrete, concrete cancer, deteriorated joints, moisture, seepage, efflorescence, rising damp and/or high-flow active leaks in concrete structures, we would be happy to assist you. You are welcome to contact us with any questions that you may have.
Brisbane office: (07) 3205 1899
Email: [email protected]
Sydney office: (02) 9346 8308
Email: [email protected]
Are you interested in finding out more about the various remedial building services we are providing?
Please click on the image below to download Waterstop Solutions Capability Statement
Waterstop Solutions Capability Statement is now available to download as PDF. (The image is clickable and opens up a link to our Capability Statement).
Good maintenance begins with a proactive approach to maintain, keep, preserve and protect a building.
Remember that seepage/water ingress into areas such as balconies, basements, concrete roofs, car parks and retaining walls, should not be ignored – call a remedial waterproofing professional today for an assessment to provide you with the best solution for your situation.
At Waterstop Solutions, we carry out a wide range of remedial works to concrete structures post-construction stage in Brisbane, Gold Coast, Sunshine Coast, Sydney and outlying areas in Queensland and New South Wales.
Equipped with major civil works experience, we can quickly determine the best approach to rectify all seepage and concrete deterioration issues.
It takes licenced remedial waterproofer and leak sealing experts like us at Waterstop Solutions to ensure that the pathways for water to ingress are properly sealed off. A depth of technical knowledge and experience, along with a proud reputation for integrity and reliability, has made Waterstop Solutions the go-to company for many Defect Managers working for major construction companies across Queensland and New South Wales.
We at Waterstop Solutions have the technical and practical expertise to diagnose the source of the leak and will provide you with our recommended solution to achieving an effective, high-quality, long-lasting repair to stop the water ingress with minimal disruption
We believe in and are committed to always delivering high-quality solutions by utilising the right products and techniques for each specific project combined with our industry-leading know-how on tap. We have a large talent pool of specialist leak sealing and concrete repair technicians with Certificate III in construction waterproofing in Queensland and New South Wales that are extensively trained in our systems and project execution methods.
The leadership positions on every Waterstop Solutions project are operated by highly qualified, certified and experienced industry professionals. Our in-house skills and expertise gained from more than 60 years of industry experience provide a full range of high-quality remedial waterproofing and concrete repair works to commercial buildings, civil infrastructures, industrial sites and residential properties. From waterproofing diagnostics, preventative and remediation solutions – All of our waterproofing solutions are quality guaranteed.