Exterior Wall

How do I waterproof my exterior wall?

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    The fundamental principle of waterproofing is to prevent water from penetrating a surface in the first place, rather than focusing on preventing it from escaping.

    This seems like it should be pretty obvious, but you'd be surprised at the number of builders, even experienced ones, who start trying to seal leaks from the inside. Be aware that finding the point of entry may not be an easy task; water can travel a long way through a structure or even completely saturate it, making it a difficult task to find the source of the problem.

    It is possible for water and moisture to penetrate the masonry and affect the interior walls of your home if the exterior walls are subjected to precipitation or a high relative humidity. This means that your walls may remain damp for an extended period of time before they dry, which may result in the growth of mould and damage that cannot be repaired.

    How can you prevent water and mould from affecting your walls? We have a wide range of external waterproofing services at Hitch Property Constructions.

    Why Do We Get Leaks?

    The majority of buildings constructed in modern times have vertical columns made of reinforced concrete along with reinforced ring beams along the top that provide the necessary strength for the walls. In the spaces in between the columns and beams, an infill of soft local red bricks or light concrete blocks has been placed, and then a skim coat of hard concrete has been applied on top. The reinforced concrete is frequently of poor quality, as evidenced by the presence of cracks and cavities, and the infill is comparable to blotting paper.

    This kind of structure is very rigid, and the frequent earthquakes that we experience in Bali (yes, lots of them, and most of the time they are so small that we don't even notice them, but every once in a while one will wake you up in the middle of the night), as well as the frequent ground movements that occur here, cause cracks in structures, typically through the walls of buildings.

    It is extremely uncommon to find a tradesman who will work logically through the symptoms of a problem and accurately identify the cause rather than taking the easy way out and treating the first thing that he sees as the problem. This is because it is easier for a tradesman to treat the symptom than it is to treat the cause.

    Exterior Wall

    How Does Inadequate Waterproofing Harm Exterior Walls?

    Walls that are not adequately waterproofed on the exterior will continue to hold moisture for a longer period of time than those that are. In addition to the fact that conditions in this environment are ideal for the growth of mould, it is possible that the damage will spread further and result in unwanted water seepage.

    Choosing the Right Waterproofer

    It is essential to select the appropriate paint for waterproofing. The best brands are those that are breathable and that permit the exterior walls to "breathe" in a way that eliminates and prevents excessive amounts of moisture from building up. In addition to that, you will require a plaster additive. Not only is using the appropriate plaster an excellent way to improve the aesthetics of the exterior wall, but it also has the potential to make the walls more sturdy. Concrete, which has been developed specifically for use in masonry and can be applied to almost any surface, makes up the best coating because it is extremely versatile.

    Because they produce the most durable seals, silicate-based brands are considered to be of the highest quality. A perfect coating that is versatile and can be used even for walls that have not been painted or sealed can be formed by applying this material in such a way that it targets the very ingredients that are used in concrete masonry. This design of the material makes it possible for it to be used even on walls that have not been painted or sealed.

    In spite of the fact that the vast majority of exterior plasters already incorporate waterproofing properties, the infiltration of water and the issues that come along with it can be avoided through the use of waterproof additives that are placed within the plaster.

    Prepping The Walls For Waterproofing

    It is essential to use filler of a high quality in order to repair and patch any holes or cracks that may be present in the exterior walls of your home before beginning the process of waterproofing them. Before grinding or sanding away any excess material, the filler needs to be given sufficient time to dry out first. This will ensure that the surface is even and free of dust when it is finished. After the walls have had sufficient time to dry, you can then proceed to apply the waterproofing.

    A high-quality roller or brush is the instrument of choice for applying waterproofing. In some cases, a second coat of paint will be required for the walls. If this is the case, you will need to wait until the first coat has completely dried before applying the second. The barrier that you construct needs to be able to withstand the infiltration of moisture. Testing is the most reliable method for ensuring that it is functional.

    How Do We Stop Water Getting Into Walls?

    Now that we know there is water behind a wall, what should we do about it?

    To begin, we should check ourselves into a detoxification centre to address our addiction to alcohol; doing so will put an end to the DTs and the bloodshot eyes.

    Your next stop should be an ashram. Participate in a nine-month long course on transcendental meditation, during which you will learn to love all living things, including cats, as well as accept the water issues that are present in your life.

    Finally, treat yourself to a relaxing massage and a close shave.

    First things first: locate the point of entry for the water. Since it is a fundamental principle of the natural world that water always flows downhill, as is common knowledge, we will begin at the highest point.

    Is the top of the wall exposed to the weather or does the roof provide some protection from it? If the roof does not overhang the wall, look along the top of the wall for cracks, even very fine cracks, and make sure they are repaired. Does the upper surface have a coating that makes it waterproof? Is the roof made of concrete, and does it have a parapet wall? It's possible that water is getting in through the joint where the concrete roof slab and the wall meet, or that it's getting in through the parapet wall and into the top of the wall below.

    Leaks from cracked concrete roof gutters

    Leaking concrete gutters are a very widespread issue on the island of Bali. It is considered to be very poor manners in this area to let water from your roof run off onto the property of a neighbour or into a street. This is because it is considered to be very messy. If a structure is built right up against the property line, as a great number of them are, then a concrete gutter is typically constructed along the top of the wall to collect rainwater that runs off the roof and direct it away from the building. These concrete gutters are plagued with two primary issues:

    1. Cracks in the gutter that allow water to enter the wall are frequently caused by ground movement, which also causes the gutter to crack. Fixing this issue might not be too difficult if the cracks aren't too large. First, the gutter needs to be cleaned thoroughly, and then the inside needs to be waterproofed; however, it is recommended that the entire gutter be waterproofed at the same time.
    2. When building wall gutters, it is common practise to make the outer wall higher than the inner wall. This configuration ensures that, in the event that the gutter becomes full of water, the water will overflow into your building either along the ceiling or down the inside of the wall. Roof gutters in Australia are typically made of plastic or aluminium and are designed with the intention of having the outer side of the gutter be lower than the inner side in the event that the gutters become full and cause the water to overflow. As a first step towards resolving this issue, check to see that the downspout of the gutter has a diameter that is adequate for the size of the surface area of the roof that it is responsible for draining, and that the outer face of the gutter has notches cut into it at strategic locations to create overflow points. These ought to naturally be set at a level that is lower than the inner face of the gutter. It is also a good idea to make sure that there is a space between the gutter and the ground where the downpipes are located. This will prevent water from getting stuck inside the pipe.

    Check the surfaces of the wall.

    When you have finished looking along the top of the wall, the next thing you should do is examine the surface of the wall. Check everything from the very beginning to the very end. Is there exposure to the elements there? Be aware that if you are in an area that experiences a lot of wind, the rain may be blown at an acute angle against the wall. Buildings with sensible architecture feature adequate roof overhangs that are angled in such a way as to direct rainwater away from the exterior walls. Additionally, roof overhangs prevent sunlight from hitting the walls, which helps to maintain a cooler temperature inside the room.

    You can prevent rainwater from entering your home by waterproofing any walls that are in direct contact with the elements. Be sure to make a note of any cracks in the wall, as these will require a different kind of repair than the rest of the wall, and we'll get to that in a moment.

    A word of caution: a wall must have ventilation in order to allow moisture to escape and evaporate in the event that it becomes saturated with water. It is not necessary to waterproof the interior as well as the exterior surfaces of a wall. If you do, you may well always have damp walls.

    Rising damp

    The rising damp should be checked for as a final precaution. If you are knowledgeable enough, you can fix this issue, which occurs frequently in areas of Bali where damp proof courses are not routinely installed. Just like you wouldn't let someone who didn't know what they were doing poach an egg for you, you wouldn't trust someone like that with this.

    The best way to solve this problem is to make a horizontal cut all the way through the bottom of the wall and the entirety of the wall itself. Yes, this must be done with extreme caution, and there are several good reasons why it cannot be completed all at once. After that, you use a high-density cement to fill in the slit.

    This feature, which is known as a sloof, will prevent water from seeping through the ground below the wall and entering the structure. Techniques that are widely marketed in Britain but not available in this country include injecting silicone solutions. These techniques are typically of very questionable efficacy. Because of the high porosity of the batako blocks that make up the walls, it is highly unlikely that they will work.

    Looking for external waterproofing Melbourne? Check out Hitch Property Constructions.

    Sealing the leaks

    Now that we have identified the root of the problem, how should we proceed with treatment? The conventional approach involves applying a thin layer of high-density waterproofing cement as a skim, but this is not an approach that many would recommend. This particular kind of waterproofing film is extremely brittle and prone to cracking. On a surface that is exposed to sunlight, the excess surface heat will cause the concrete skim to crack away from the wall beneath it. This will allow water to enter the surface, and the water will be able to travel between the surface beneath the concrete skim and the surface above it.

    The prefered method of treatment involves applying a thick coat of polymer paint with a brush. It is available in a variety of colours. There are localised variants that are sold at a lower price, but my guess is that you get what you pay for. Cracks require specialised treatment as they are likely to experience additional movement in the future. Raintite comes with a material that resembles a thick bandage and functions as a membrane. Apply a layer of Raintite polymer to both sides of the crack, place the bandage over the crack running the length of it, and then paint the bandage so that it is completely saturated with the polymer. In the event that the crack moves, the bandage will stretch slightly while still maintaining its waterproof properties. It is important to note that these polymers have a strong aversion to water.

    The surface needs to be squeaky clean and completely dry before the application of a waterproofing polymer. First, the surface needs to be cleaned of any loose paint, moss, or dirt, and then it needs to be dried. Before beginning to waterproof it, you should wait a day until the surface as well as any cracks have completely dried out.

    Dulux Weathershield is the most well-known and well-respected waterproof paint for exterior walls; however, in order to ensure that the wall can still breathe, you should use it for general waterproofing of walls that are in good condition.

    Since we have finished dealing with the challenging issues, we can now move on to the less challenging issues. Teach the chimpanzee to balance on one foot while holding the pan with the other, then have it pick up an egg with one hand and a spoon with the other, all while standing on its other foot.

    Simple Steps to Waterproofing Exterior Walls

    Check walls for faults. 

    If the exterior walls become damp due to rainwater or moisture, the best solution is to waterproof them. However, this only applies if the walls are already damp. It is essential to get rid of any other factors that may be contributing to structural dampness before beginning your search for waterproofing products. It could be anything, from cracks in your bricks to condensation on the inside of the wall to a burst water pipe. The possibilities are endless. After you have resolved the issue, you can proceed to take preventative action by applying a waterproofer.

    Clean your gutters 

    The problem with clogged gutters is not only that water may flow over the edge and down your walls, but they also retain rainwater, which is gradually absorbed by the roof's wood or fascia boards, which can lead to a series of problems, such as rotten wood, leaks, and mould. The problem with clogged gutters is not only that water may flow over the edge and down your walls, but it also retains rainwater. Simply cleaning your gutters twice a year will allow you to avoid all of these issues and maintain the health of your home.

    Select the right waterproofer 

    Homeowners now have access to a variety of waterproofing products that can assist them in protecting their houses from moisture that comes from the environment. The following is a list of products that you should think about purchasing:

    • concrete waterproofing coating is a cement-like product that adheres to masonry and concrete in a permanent manner; it can be applied to any surface, including painted walls; and it can prevent water from penetrating concrete.
    • silicate-based concrete sealer, which reacts with the ingredients in masonry and concrete to form a waterproofing coating; this sealer can only be used on unsealed or unpainted walls;
    • waterproofing paint, which is comparable to acrylic wall paint, with the primary distinction being that it provides superior waterproofing performance. It is of the utmost importance to select a formulation that is breathable and that has been specifically designed to enable walls to breathe and get rid of moisture. It is possible to apply the product to surfaces that have already been painted.

    Use plaster waterproofing additive. 

    Plastering can help improve the aesthetics of a building, make walls more solid, and protect them from the infiltration of moisture. Even though the majority of exterior plasters have properties that make them waterproof, you can eliminate water infiltration issues and stop them from happening in the future by merely adding a waterproofing admixture to the plaster.

    Prepare your walls for waterproofing. 

    Before applying any product to waterproof the exterior walls of a building, the walls themselves need to be repaired and brought up to a satisfactory level. This indicates that in order to repair cracks and holes, you will need to make use of a filler of sufficient quality. Before grinding the filler, ensure that it has reached its maximum level of dryness. After that, smooth down any rough or uneven spots with some sandpaper, wash away any dust on the surface with some water, and wait for the walls to completely dry to ensure that the waterproofer will adhere well to the substrate.

    Apply the waterproofer 

    When applying the waterproofer, you can do so with either a roller or a brush. If a second coat is necessary, wait for the first one to dry completely before applying the second one in its entirety. Make sure you use a sufficient amount of the product to establish an impregnable barrier against infiltration.


    It is essential to carry out a water-tightness test in order to evaluate the efficiency of the products utilised for waterproofing the exterior walls of a building. For the purpose of this test, water should be sprayed on the surface of the wall for a couple of hours while maintaining a 30 degree angle with the nozzle. If a moisture metre indicates that there is no moisture in your home, then your house will pass the inspection. If you waterproof the exterior walls of your home, you will not only be able to prevent serious damage, but you will also be able to increase its value.

    Proper Exterior Waterproofing

    To properly waterproof the exterior of a building, the most important thing that is required is a high level of care. Yes, you must care. You are required to make use of the appropriate materials, take your time, and have pride in the finished product. If you do not have these things, the waterproofing of your home will not be done properly.

    There are four primary mechanisms that are responsible for the transfer of moisture from the exterior of the building to the interior of the basement. The first of these is water flow. If the path with the least amount of resistance leads into your basement, then that is where the water will flow. Water always takes the path with the least amount of resistance. The capillary action comes in second. Concrete is a porous material that despite its hardness has a porous structure. Consider that the capillary action is similar to a wick. As concrete cures in water, the water is absorbed by the concrete, which continues to absorb water until it is completely saturated. The concrete then releases moisture and water vapour into the interior of the building as it continues to cure.

    Next is vapour diffusion. Similar to the way that capillary suction works, vapour diffusion involves the movement of water vapour. A structure needs only the tiniest of cracks or crevices for water vapour to be able to enter it and raise the humidity levels. Last but not least, the flow of air. When you open a door or a window, not only do you bring fresh air into the house, but you also draw air from the lower levels of the house up to the levels where people actually live. The term for this phenomenon is the "stack effect." Your house functions much like a chimney, drawing air from the lower levels to the higher levels. The basement is the source of forty percent of the air that circulates throughout our homes.

    At Hitch Property Constructions, we offer Melbourne external waterproofing services.

    What Should You Do?

    If water from the outside is getting into your basement or crawlspace, you need to make sure that the exterior of your home is properly waterproofed. Your home will need to be excavated in order for you to successfully waterproof it. It will be necessary to uncover the footing, and solutions will have to be found for all of the exterior problems.

    After the foundation walls have been cleaned, a polymer waterproofing product that can be sprayed on or rolled on will need to be applied. After the coating has had time to dry, it will need to be covered with a dimple board product, which not only safeguards the newly sealed surface but also improves the water's ability to drain downward. The next thing that needs to be done is to put in a system of drainpipes that have the right kind of slope for continuous drainage. Depending on the layout of the site, this slope may lead to a sump pit or it may lead to daylight. After that, a clean rock that is 34 of an inch thick is placed over the drain pipe. Depending on the conditions of the soil, this rock backfill could be anywhere from one foot up to sixty percent of the wall's height. Geotextile material that is non-woven is wrapped on top of the rock to help filter soil without clogging up the system. After the installation of the geotextile material, the soil backfill process can begin. The backfill soil must be native clayey soils that are able to resist the intrusion of water. Backfilling with loose soils creates a highway for the water, in contrast to using clay soils, which drive water away from the area.

    Waterproofing the exterior of a building in the correct manner is not a simple task and is not something that unqualified individuals should attempt. You are guarding your home, so it is important that the task be completed properly and offer a long-term answer to the problem with your house. It is important to keep in mind that waterproofing the exterior walls of your home cannot stop water from moving deeply below your foundation walls. This water might make its way through the floor of your basement or crawlspace.

    In situations like these, an interior drainage system will supplement the efforts you put forth on the exterior, rather than taking their place. An interior drainage system is not waterproofing. The excess water that collects around and under your home's foundation can be alleviated with the help of interior drain systems, which are a form of water management.

    Also, keep in mind that the sump pump system needs to be up to the task if you are going to move water from the outside into the basement using that system. It is possible to divert the water away from your house using modern sump pumps, sump pumps with battery backups, and sump basins of the highest quality.

    Groundwater can be directed away from the foundation and floor of your basement using foundation drain tile systems. These systems are designed to drain groundwater. It is imperative to instal an effective foundation drainage system in order to achieve both a dry basement and a solid foundation.

    FAQs About Exterior Wall

    Waterproofing a wall from the outside is relatively straightforward and can be finished in a few straightforward steps.

    • Next, you will need to apply a waterproofing sealant to the wall so that it can continue to function properly.
    • In the end, you will need to apply a membrane to the wall that acts as a waterproofing agent.
    • After applying the membrane, you must wait at least twenty-four hours for it to dry before conducting any test on it.

    You can easily waterproof your wall from the outside by following these steps, which will also help to keep the inside of your home dry and comfortable.

    If your home's exterior walls are not waterproofed, you can face damage from invading moisture. Damp walls are excellent breeding grounds for mildew and mould, which can damage the home and lead to health problems for occupants. With proper waterproofing of a home's exterior walls, however, such damage can be avoided.

    The added benefit is that it still allows your walls to 'breathe'. Without breathability, the dampness already in your walls can't evaporate and allow your wall to dry out. Water repellent creams dry clear, allowing any exposed brick to keep its original appearance.

    Brick is extremely porous so that it can absorb water like a sponge; over time, water absorption can cause crumbling and cracking in the brick. Apply a sealer to your exterior brick for protection against water damage and minimize moss growth.

    If that's an issue, clean the wall with a mild masonry stain remover or detergent solution. Rinse, then allow the brick and mortar to dry thoroughly before applying sealer. Among the longest-lasting brick, sealers are made with polyurethane or acrylic, which can give the brick a slight sheen.

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