how to waterproof an external balcony (3)

How To Waterproof An External Balcony?

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    Whether you're starting from scratch or making some changes to an existing balcony or terrace, it's crucial to know how to assess your needs and then pick the waterproofing solution that will work best for you. Knowing how to pick the right waterproofing system for the job is also crucial. As a result, its realisation must be flawless, with special focus on all types of details and the correct treatment of them, as these are the primary entry points for water leaks and the problems they cause.

    The first step in waterproofing a balcony or patio is to assess its current state. It's important to do this since restoring or installing a new waterproofing system on a balcony or terrace might include a wide range of solutions and steps, some of which are more invasive than others, depending on the balcony's or terrace's current condition of preservation.

    Assessing the current flooring's condition is the first step in deciding whether or not to replace it. The preservation status of this layer may be evaluated with the least amount of effort. One way to perform such an analysis is to verify whether or not the joint volumes are uniform. This is significant because water usually enters a structure through the joints, where the finish has no influence on water resistance.

    This will cause the water to start eroding the entire pack, which will have devastating effects on its individual parts. All of the flooring's parts can be checked for wear and tear simultaneously. Any cracks or breaks in them, even if they are designed for outdoor use and are hence waterproof, nevertheless allow water to enter.

    Flat roofs over added living, kitchen, or bedroom space, as well as upper-floor apartments, are common locations for balconies and terraces. These sorts of outdoor spaces are typically located atop residential dwellings. There should be a lot of care put into sealing the balcony's surface and then waterproofing it.

    Waterproofing a balcony is important because it prevents water from entering the space below it and causing damage. If you live in an area that gets a lot of rain or snow, you should be sure to waterproof the balcony floors and walls. This is not something to be taken casually.

    A recent statistical analysis revealed that the "Balcony Waterproofing" sector of the building envelope experienced the greatest failure rate overall. Balcony waterproofing costs only 1.8% of the total construction budget, yet accounts for an incredible 83% of all complaints about buildings' flaws. There can be major ramifications if the procedure of waterproofing flat roof balconies, room balconies, and terraces is not well-planned and carried out from the start.

    You can protect your balcony from water damage in a number of ways, and while there is a lot of cutting-edge equipment and materials available, you don't have to use any of it. Typically, concrete or lumber is used for balcony roofing, and then a waterproof coating is placed to ensure the longevity of the material. It's important to remember that the difficulties encountered while working with wood or metal during construction are distinct from those encountered when working with concrete, and vice versa. If you haven't used the right system, or if the waterproofing was done poorly, you may have to constantly fix the balcony's surface.

    Efflorescence, the buildup of calcium crystals and salts that discolours the top edges and underside of brickwork, cannot form if there is no water present. Efflorescence is another name for this phenomenon. The chosen material must be able to expand to the same extent as the surrounding components, while also adhering to them to form a secure bond and seal.

    For the structure to be waterproofed, penetrating work and fixing down must first be finished. A fence in such a location will likely require baluster posts, which are vertical supports that must be joined to the building's underlying structural components. In this case, the balcony's sealer or waterproofing compound must adhere to and seal around the steel balustrade posts, preventing water from getting in. In the event of a leak, the steel will expand more than the material you've chosen, and if that material is fragile, you've set yourself up for disaster.

    Sealants made from polyurethane, including Sika flex 11FC, do an excellent job of protecting the connection between dissimilar materials. These materials offer great resilience to high and low temperatures, can adhere to a wide variety of substrates (glass, rubber, stone, steel etc.), and can withstand UV light, which is particularly useful in a highly exposed location. Any time something is fastened to a completed roof, special care must be taken to prevent water intrusion by sealing the region properly.

    How to Prevent Water Damage to a Balcony or Terrace?

    how to waterproof an external balcony

    The first step in waterproofing a balcony or terrace is deciding if a complete re-waterproofing is required or whether only the existing system needs to be fixed. If the first option applies, then waterproofing must be done again. This assessment will tell us when we need to take action in terms of waterproofing.

    • We are rebuilding the screed in order to waterproof the balcony.
    • The steps necessary to waterproof the flooring of a balcony or terrace.
    • Incorporation of new screed-protecting waterproofing membrane
    • The new coating should be applied after the balcony or patio has been waterproofed.

    In the former case, putting in place the waterproofing system is simpler, but in the latter, which entails reconstruction, it is necessary to continue evaluating the existing situation. The second case is an opportunity to perform a less invasive surgical method. Before cleaning the support with a pH-neutral detergent, deposits, any efflorescence, or remnants of previous treatments, including waxes, are removed.

    After the grouting on the terrace has dried, it can be redone using outdoor putty, which will have superior impermeability. Because of these features, the packaging may be put back together without losing any of its contents. Finally, we're going to move forwards with various treatments, most of which include film-free, see-through products. These solutions make it possible to waterproof an entire balcony or terrace at once, with special attention paid to high-risk locations like the joints. This will guarantee that the waterproofing on the balcony's or terrace's top layer will remain in place until any necessary repairs have been made.

    We move on to repairing the terrace's waterproofing system in a different way after it becomes clear that water is infiltrating the finishing layer. Taking this step necessitates the removal of the damaged flooring, as well as the glue and waterproof coating that serves to protect the screen.

    From this point on, we will be re-waterproofing the screed with liquid goods that are also waterproof, bonding the new coating with a cementitious glue suitable for the substrate type, and using grout that is waterproof and made for outdoor use.

    Balcony and Terrace Water Leaks Should Be Avoided.

    When installing flooring on a balcony or terrace, it's important to use joints of the proper size and made from the right material. For instance, due to the rise in popularity of floors with large tiles, it is important to ensure that the joints between the tiles are suitable for such floors, preventing future cracks in the flooring and increasing the danger of infiltration caused by friction.

    Thresholds, which connect the balcony or terrace to the window-door that leads inside the house, also warrant special consideration. As a general rule, these should be at least 1 inch higher than the walkway of the balcony; however, increasingly, for aesthetic reasons, they are made at the same level as the floor, so the function of disposing of rainwater is given only to the slope of the package. It's important to note that the slope of the package has no bearing on the drainage of the

    Details like wall-floor joints, expansion joints, and drains require additional waterproofing measures like butyl gauze, strips or tapes due to the increased likelihood of leaks at these locations due to the complex geometric conformation they have. These components are made to go along with the various planned waterproofing systems.

    Terrace and Balcony Waterproofing Options

    Signs of increased infiltration danger include the onset of winter, rain, and ice, all of which, if unchecked, can cause long-term structural damage to a building. The symptoms can be dangerous if the underlying risk is not addressed. Waterproofing that has worn out or been improperly installed is usually to blame for issues of this kind. Below, we'll examine a variety of methods that might be used to avoid or deal with these issues on balcony and terrace flooring.

    Waterproofing: What to Think About First?

    It is the designer's obligation to choose the best way of waterproofing for the exterior flooring in newly constructed homes. In order to ensure that the waterproofing is properly supported, it is recommended that a drainage membrane be installed on the substrate's underside.

    In order to prevent water from becoming stagnant and damaging the building, the regulations state that "the indication of a drainage and protection membrane, put between the substrate and water barrier, is a precaution to prevent water from infiltrating the structure." This precaution is taken so that moisture is not trapped inside the building. However, when making improvements, it's important to weigh many factors before settling on the best course of action based on a few key criteria. First, we need to examine the area where the intervention will take place.

    • Find out how badly the flooring and substrate have been damaged.
    • Verify if the structure's layers are right.
    • It is crucial that the flooring has the appropriate slope.
    • Verify that there are no splits or spaces between the various levels.

    Based on the details presented below, you can select the option that works best for the balcony or patio in question.

    Pick The Best Waterproofing Method For Your Remodel.

    how to waterproof an external balcony (2)

    By evaluating many factors, you may settle on the best plan for the outside space, whether it is a balcony or patio. If the flooring is in excellent condition, waterproofing it may be the only essential step. However, if the tiles have issues like cracks or holes, it's best to get rid of them and then waterproof the substrate layer underneath. If the substrate itself is of poor quality, the best way to prevent future infiltration is to waterproof the layer beneath the substrate.

    Avoiding Tile Replacement When Waterproofing

    If the flooring is in good condition and there are no cracks or tenting, then liquid waterproofing is a great solution that can be applied without removing the tiled surface. The material may be rolled or brushed across the entire surface in a short amount of time without leaving any gaps, and the resulting thickness is only a few millimetres at most.

    When done correctly, this approach is immune to changes in temperature, bad weather, chemicals, or stagnant water as long as you follow the manufacturers' guidelines for using the liquid membranes. Consider the compatibility of the product with the existing flooring before finalising the deal with the supplier. We offer a wide variety of tiling renovations in Melbourne to give your property a modern appeal.

    Methods for Preventing Water Damage to the Subfloor under Tile

    Damaged or unusable flooring necessitates removal and complete subfloor layer interference in order to repair or replace it. If the floor needs to be replaced, this is a necessary step. Waterproof membrane rolls and waterproofing solutions are the two most popular methods of waterproofing.

    Waterproofing Methods That Use Rolls of Membrane

    There are a variety of rolled membrane solutions available on the market that can be used to waterproof the substrate. The most popular areself-adhesive, bituminous, rolled waterproofing membranes that may be installed using hot air welding on-site. The surface must be dry, dust-free, and pristine. After the adhesive membranes are set up, thinset can be applied in order to get the tiles ready to be set.

    If the waterproof layer underlying the substrate has not been damaged, you can use a rolled-up polythene membrane or other more hygienic and time-efficient option. Floortec is a polythene-based membrane that has a non-woven fabric backing that has been bonded to it for optimal waterproofing. The use of such a method of watertightness is possible. Floortec, with a total thickness of only 3 mm, not only increases load resistance but also compensates for structural tension, regulates moisture that rises through the installation, and improves the waterproofness of the substrate without severely impacting the flooring's interior. Floortec's overall thickness is only 3 mm, but it still offers all of these advantages. The tiles can be laid once the membrane has been bonded to the cement subfloor with adhesive cement.

    System for Waterproofing using a Cement-Based Liquid Compound

    As an alternative to a bituminous membrane, a cement-based liquid layer that is easy to put on top of the substrate may be considered. The final result is a cement-based mixture to which water-resistant polymers and other substances have been added.

    The next step is to lay the tiles and tile adhesive on top of this layer. We can expect a simpler procedure than the one that was previously used. However, the cement coating is not entirely impermeable in practise. Temperature changes may cause the cement layer to expand or contract, creating a microscopic crack that allows a trickle of moisture to seep through to the layer below. Restoration projects where it is known without a shadow of a doubt that the substrate is in pristine condition, free of fractures or even minute fissures, are prime candidates for this approach.

    Methods for Waterproofing the Subfloor

    The only method to stop the infiltration problem from getting worse and preserve the substrate is to intervene beneath it. The operation must begin with the application of a waterproofing layer, followed by the installation of a drainage membrane to prevent water from pooling and to allow water to escape from the top layer of the draining substrate, as required by rule UNI11493-1. That's what you need to do if you want the finest outcomes.

    Waterproofing Method Using a Bituminous Membrane

    Bituminous membranes are the standard method for waterproofing the space below the subfloor of terraces and balconies. These membranes are manufactured through the distillation of crude oil and sold in premade rolls.

    To further increase the roll's durability, a glass or polyester fibre armature is placed within its thickness. It is recommended that a bituminous membrane, with a thickness of 4 millimetres, be put in pedestrian areas such as terraces and balconies in order to increase the mechanical resistance and keep the elongation feature that is unique to this material. To make the sheets of prefabricated rolls even more user-friendly and secure in their attachment to the surface, flame bonding is included. For situations where using an open flame would be unsafe, these membranes can also be purchased with an adhesive layer. Although these are easier to use, their effectiveness has suffered as a result.

    The Significance Of Membrane Drainage

    The drainage membranes that are laid beneath the substrate of the building are the unsung heroes of the building's safety. Water is the primary culprit in the deterioration of balconies and terraces, as it causes damage when it seeps into the inside of the substrate and erodes the many waterproofing layers over time.

    The drainage membrane's unique design ensures that this kind of problem never arises. Draintec 8 is the membrane that our experts recommend because it allows water to drain through multiple drainage channels while compensating for hydrostatic stress caused by direct contact between the substrate and the bitumen-based membrane.

    The item's unusual shape serves to both sustain the load and reduce the compression of the load caused by pedestrian or load passage. While only 8 mm thick, Draintec 8 is actually made up of two laminated layers. The first is a polythene base that has been equipped with cone-shaped features for separating and draining liquids.

    Layer two is layered on top of the first and is constructed of non-woven fabric. To prevent the channels from being clogged and the membrane's overall effectiveness from decreasing, this layer is present. We advise using Draintec 8S, a nett with an even more open weaving structure than Draintec 8, as a water-draining substrate.


    Balcony waterproofing is crucial because it stops water from seeping into the room below. It's just as important to know how to properly select the appropriate waterproofing system. Depending on the state of preservation of the balcony or patio, some methods may be more intrusive than others. Even though it only contributes for 1.8% of the entire budget, 83% of all complaints may be traced back to leaking balconies. The selected material must adhere to the surrounding components and expand to the same degree as they do in order to produce a reliable connection and seal.

    Taking necessary precautions to seal off the area and keep water out is of utmost importance. Polyurethane sealants, such as Sika flex 11FC, do a great job of guarding the joint between two different substances. In addition to being very adhesive, these materials also exhibit remarkable resistance to extremes of temperature. Joints of the suitable size and substance are crucial when laying flooring on a balcony or patio. No water should be leaking onto the balcony or terrace.

    Issues mainly stem from worn out or incorrectly installed waterproofing. Buildings need to be waterproofed so that water doesn't pool and cause structural damage. When tiles have damage, such as cracks or holes, it is advisable to replace them and then seal the underlying substrate with waterproofing material. A excellent option is liquid waterproofing, which can be done without having to remove the tiles. The two most common approaches are waterproof membrane rolls and liquid waterproofing treatments.

    Floortec is an extremely effective waterproofing solution since it is a polythene membrane with a non-woven fabric backing that has been glued to it. There is the possibility of using a liquid compound based on cement as part of a waterproofing system. A common problem with terraces and balconies is water seeping into the subfloor. It can only be stopped by first installing a drainage membrane, and then a waterproofing layer. The crude oil distillation process creates these membranes, which are then packaged and sold in rolls.

    Draintec 8 alleviates hydrostatic stress brought on by the membrane's direct contact with the substrate by directing water flow through a network of drainage channels. The unconventional form of the item serves to prevent the load from being compressed as a result of normal pedestrian or load traffic.

    Content Summary

    1. It is important to know how to evaluate your requirements and choose the waterproofing solution that will work best for you, whether you are beginning from scratch or making some improvements to an existing balcony or terrace.
    2. It's just as important to know how to properly select the appropriate waterproofing system.
    3. In order to begin waterproofing a balcony or patio, it is necessary to first determine its existing condition.
    4. This is crucial because, depending on the balcony's or terrace's existing state of preservation, restoring or installing a new waterproofing system may need a broad range of solutions and stages, some of which are more invasive than others.
    5. The first thing to do when trying to decide if you should replace your flooring is to take stock of its condition.
    6. It is possible to examine the flooring for signs of wear on all of its portions at once.
    7. The balcony's surface should be meticulously sealed and then waterproofed to prevent water damage.
    8. Waterproofing the balcony floors and walls is essential if you live in a region that receives a lot of precipitation, whether it be rain or snow.
    9. According to recent data collection and analysis, the "Balcony Waterproofing" section of the building envelope has the highest failure rate.
    10. Waterproofing balconies accounts for 83 percent of all building complaints despite costing only 1.8 percent of the overall construction price.
    11. Negligence in the waterproofing process for flat roof balconies, room balconies, and terraces can have severe consequences.
    12. There are a variety of methods you may use to prevent water damage to your balcony; you are not need to utilise the most cutting-edge technology.
    13. Balcony roofing is often made from concrete or hardwood, with a waterproof coating added for durability.
    14. Constant maintenance on the balcony's surface may be required if the wrong technology was employed or if the waterproofing was done badly.
    15. Work on penetrating and fastening the structure to the ground must be completed before waterproofing can begin.
    16. Waterproofing the balcony means the compound or sealer adheres to the steel balustrade posts and creates a tight seal.
    17. If the material you've chosen to contain the leak is flimsy and the steel expands beyond it, you're asking for trouble.
    18. Polyurethane sealants, such as Sika flex 11FC, do a great job of guarding the joint between two incompatible substances.
    19. These materials are beneficial in a highly exposed area since they are resistant to both high and low temperatures, they stick to many different surfaces (glass, rubber, stone, steel, etc.), and they are unaffected by ultraviolet light.
    20. Determining if a full re-waterproofing is necessary or merely the current system needs to be fixed is the first stage in waterproofing a balcony or patio.
    21. In terms of waterproofing, this evaluation will alert us to when we need to take action. In order to make the balcony watertight, we have to repair the screed. The procedures involved in making a balcony or terrace's flooring watertight.
    22. The terrace's grouting can be repaired with outdoor putty after it dries; this new material will be more impermeable.
    23. And now, we're ready to move on with other treatments, the majority of which involve film-free, transparent products.
    24. These methods allow for the joint areas and other potential weak spots on a balcony or patio to be addressed at the same time and effectively waterproofed.
    25. This will ensure that the top layer of waterproofing on the balcony or terrace remains in place until the damage has been repaired.
    26. Going forwards, we'll be utilising waterproof liquid products to re-waterproof the screed, waterproof cementitious glue appropriate for the substrate type to adhere the new coating, and waterproof outdoor-grade grout to finish the job.
    27. Joints of the suitable size and substance are crucial when laying flooring on a balcony or patio.
    28. To avoid future cracks in the flooring and the increased risk of infiltration caused by friction, it is essential to verify that the joints between the tiles are adequate for floors with large tiles, as their popularity has recently increased.
    29. These should be at least 1 inch higher than the balcony's walkway for optimal drainage, but increasingly, they are created at the same level as the floor for aesthetic reasons, leaving the slope of the package to handle rainwater runoff.
    30. Details like wall-floor joints, expansion joints, and drains necessitate additional waterproofing measures like butyl gauze, strips, or tapes due to the increased likelihood of leaks at these locations due to their complex geometric conformation, despite the fact that the slope of the package has no bearing on the drainage of the contents.
    31. Winter's arrival, precipitation, and ice are all indicators of a heightened risk of infiltration, which, if left unchecked, can result in permanent damage to a building's structure.
    32. Most of the time, faulty or outdated waterproofing is to blame for these kinds of problems.
    33. A range of solutions to these problems on balcony and terrace flooring will be discussed below.
    34. The designer of a new home must decide on the most effective method of waterproofing the outer flooring.
    35. Installing a drainage membrane on the underside of the substrate is advised to provide adequate support for the waterproofing.
    36. The laws specify that "the provision of a drainage and protection membrane, placed between the substrate and water barrier, is a precaution to prevent water from infiltrating the structure" to stop water from pooling and causing damage.
    37. Liquid waterproofing is a terrific option that doesn't require tearing up the tiled surface if the floor is in good shape and free of cracks and tenting.
    38. If your floor is damaged or unworkable, it must be removed and the subfloor layers must be interfered with completely before you can fix or replace it.
    39. The two most common types of waterproofing are the use of waterproof membrane rolls and liquid waterproofing treatments. Waterproofing the substrate is possible using any number of commercially available rolled membrane solutions.
    40. A rolled-up polythene membrane or other more hygienic and time-efficient solution can be used if the waterproof layer beneath the substrate has not been compromised. This method of watertightness can be used.
    41. After adhering the membrane to the cement base with adhesive cement, the tiles can be installed. Instead of a bituminous membrane, a cement-based liquid layer that can be spread out easily on top of the substrate could be used.
    42. After adding water-resistant polymers and other ingredients to cement, the resulting composition is watertight. After that, you can proceed to instal the tile and glue.
    43. Protecting the substrate from further infiltration requires taking preventative measures from below.
    44. First, a waterproofing layer must be applied, and then, per Rule UNI11493-1, a drainage membrane must be installed to prevent water from pooling and to allow water to escape from the top layer of the draining substrate.
    45. Waterproofing the area beneath the subfloor of terraces and balconies is often accomplished using bituminous membranes.
    46. In order to strengthen the mechanical resistance and preserve the elongation feature that is unique to this material, a bituminous membrane, with a thickness of 4 millimetres, is recommended to be installed in pedestrian areas such as terraces and balconies.
    47. Substrate drainage membranes are the unsung heroes of structural integrity.
    48. When water penetrates the interior of the substrate and eats away at the multiple waterproofing layers, as it does over time, the result is a deteriorating balcony or terrace.
    49. Our research has shown that Draintec 8 is the best membrane for mitigating hydrostatic stress due to direct contact between the substrate and the bitumen-based membrane by providing various drainage channels.
    50. The unconventional form of the item serves to prevent the load from being compressed as a result of normal pedestrian or load traffic.
    51. This layer is there to keep the channels open and the membrane functioning at its best.

    Frequently Asked Questions About External Balcony

    Bituminous membrane waterproofing system. Bituminous membranes are the most popular system used to waterproof under the substrate of terraces and balconies.

    Balcony waterproofing is required to protect an area underneath the balcony from persistent water ingress. For areas vulnerable to snow or heavy flooding, the waterproofing of balcony surfaces is an integral part of the building process and cannot be taken lightly.

    Use a paintbrush to seal the edges and perimeter of the balcony. Seal between banister posts and railings and make sure to cover all visible areas of the concrete. Use a paint roller to apply the sealer to the rest of the balcony, painting yourself off the balcony and into the house as you go.

    Butyl rubber is an ideal membrane for balcony waterproofing, given it can be applied either under a screed or directly below most surface finishes. Butyl rubber waterproofing can be applied to most substrates providing they conform to a minimum specification, including concrete, plywood, and cement sheet.

    Typical costs for waterproofing a balcony, walkway or terrace are approximately $4.00-$6.00 per square foot and must be coated every five years. On the same day, wearing surface coating is $7.00-$9.00 per square foot, and the life is ten years.

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