Concrete Planter Box Waterproofing

Identifying leaking planter boxes

Many homes and commercial properties install planter boxes to house their flowers, trees and shrubs.  Planter boxes are generally situated on balconies, terraces, decks and pathways and if not sealed or waterproofed correctly (or at all) can quickly develop water leaks with the potential to cause costly water damage. 

Waterproofing a planter box will protect it from developing cracks that would allow water to leak onto surrounding areas and penetrate internal areas if over, or adjacent to, interior finish work. However, insufficient, damaged or no waterproofing gives rise to excess moisture, which promotes the growth of fungus and bacterial allergies, delaminates the surface coatings and produces dry rot.  Additionally, waterproofing will provide a longer service life for your planter boxes while also guarding against leaching of highly alkaline salts into the soil which could potentially stunt your plants growth.

Price to waterproof a planter box

The price associated with planter box waterproofing will vary.  The price is dependent on the size and design of the structure, its location/placement, weather exposure and the requirements of the client.  You are welcome to contact BUSS’ professional waterproofing team who are available to provide you with a free assessment/inspection and quote.


    Did you know that currently waterproofing is unregulated in WA? How do you know who to trust? Read more...

    Leaking Planter Box Causes?

    Along with the above identifiers of leaking planter boxes, the most common causes are:

    Tree roots and other plants

    The tree root will follow the moisture trails through lap joints or small penetrations in the membrane and tear it apart resulting in water leaks.  Also, the roots of an aggressive tree can result in cracks to planter boxes and will compromise the waterproofing membrane.

    General movement

    The general moving of the building structure where planter boxes reside can result in tearing of the waterproofing membrane at the floor and wall junctions.  Once tearing has occurred, water can travel freely through the planter boxes thus causing defects.

    Overwatering and heavy rain

    Hydrostatic pressure, which is caused by excessive moisture in the soil, can force water to penetrate through cracks or imperfections of planter boxes; it’s commonly seen after heavy rains but can also occur through overwatering.

    How to waterproof a cement planter box?

    In order to waterproof a planter box, thorough surface preparation is very important in ensuring proper adhesion of the membrane to the substrate.  All walls/joints must be secured to the corners by polyurethane and membrane applied. Protection boards must be fitted to the walls and drainage screenings filled, geofabric applied before soil/plants are placed.

    Engaging a professional waterproofing specialist to waterproof a planter box will ensure that the procedure has been completed in line with current Australian Standards; and effectively upholding your product warranty.  It’s important to note that the most suited product(s) and/or fit for purpose waterproofing membrane must be selected for the planter box and this will depend upon its shape, substrate, plant matter and soil it contains, it’s placement and surrounds as well as the amount of weather exposure. 

    Dangers of DIY concrete planter box waterproofing

    DIY of concrete planter box waterproofing is not recommended, as inexperience can and will lead to failure of the membrane. When the planter box waterproofing membrane fails, cracks will develop and leak onto surrounding areas such as balconies, decking or paved areas, as well as internal areas if positioned over or adjacent to interior finishes, and the water leaks will promote the leaching of highly alkaline salts into the soil of the planter box which will stunt the growth of the plants.

    Installation of planter box waterproofing is best completed by a professional waterproofing specialist, thus guaranteeing the correct product selection for the planter box design. A professional will ensure that the technical procedures required for preparation and installation are in line with current Australian Standards; thus, adding value to your investment with no damage or risk.


    Drawing on our experience and industry best practice, BUSS’ team have been servicing our clients in the commercial, industrial, residential, mining and resources market for more than 20 years.  Our specialist remedial team have been applying their expertise in completing condition assessments, creating action plans to remediate issues, developing repair methodologies, providing product recommendations and undertaking repairs via trusted techniques to eradicate underlying problems and renew assets to their desired state for our clients.

    Our proven track record in effective remedial solutions and quality workmanship, supported by our affiliation with leading industry organisations – Australian Institute of Waterproofing, the Australasian Concrete Repair Association and Strata Community Association, along with our Cert III accredited applicators, offer our clients peace of mind for all their remedial repairs.  Our association with these leading organisations allows us the advantage of being one of the most qualified, trusted and reputable remedial contractors in WA.

    BUSS is your ‘go to’ contractor for your planter box waterproofing needs in Perth and the metro area.  For more information, please feel free to contact us below, or call us on 08 9444 1732 .

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