Waterproof A Wall

How do you waterproof a wall?

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    Whether you're building or renovating a house, you should waterproof the walls.

    This is especially important for those who live in areas with a lot of rainfall or extreme humidity, as these conditions can cause walls to stay damp for a long time and cause moisture to travel through the paint and affect the internal structure. It can cause structural damage, mould infestation, and an unsightly appearance. This threatens your home's foundation.

    If you don't want to spend money and time fixing your home, waterproof your walls. There are several ways to waterproof a wall, but it's best to hire a pro rather than risk a costly and time-consuming DIY disaster.

    Monsoon season may bring relief to many, but homeowners must prepare for water leakage. Your exterior walls get wet during this season. When exterior walls are exposed to rainwater or high humidity, water and moisture can affect interior walls. Your walls may stay damp for a long time. So, mould and mildew grow on your wall, causing damage and water leakage. If you waterproof your house before heavy rain, you can keep it safe and enjoy the rain. Here are some tips to prevent wall dampness.

    At Hitch Property Constructions, we offer the best range waterproofing services to rectify your water issues.

    Why do we get leaks?

    Most modern buildings have reinforced concrete vertical columns and top ring beams for strength. Between columns and beams, light concrete blocks or soft local red bricks are infilled with hard concrete. Reinforced concrete often has cracks and cavities, and infill is like blotting paper (sorry you might not remember that, like a sponge).

    This sort of structure is very rigid, and the regular earthquakes we get in Bali (yes, we get lots, usually so small we don't even notice them but sometimes one that will wake you up in the night) result in cracks in structures, usually through building walls.

    It's rare to find a tradesman who will logically identify a problem's cause rather than treating the first thing he sees.

    Waterproof A Wall

    How to Waterproof Your Walls – A Step-by-step Guide

    Check for any cracks in the walls and seal them.

    Walls can crack over time, usually at the weakest point. Builders add wall framing to instal doors and windows. These areas are weaker than the rest of the wall, so cracks begin there. Cracks allow moisture into your structure, causing damp walls. Cracks must be filled with putty. Before monsoon, do this to prevent leaks.

    Exterior Paint

    There are two main purposes for exterior paint. First, your paint should make your home look good. Exterior paint also provides a protective barrier for your home. The right paint protects wood, vinyl, metal, and stone from water. Use the right paint and undercoat to waterproof your home.


    Around windows, draughts can enter or warm air can escape. Old windows lose seals in the window and around the frame. Re-caulk the frame if you can't buy new windows. Quality caulking with professional installation lasts 5-7 years, so don't skimp. Bathroom caulking can also help. Check the sink, shower, and tub. Caulk seals most home fixtures.

    Waterproofing During Construction

    In-construction waterproofing is best. High-quality liquid waterproofing compound can be used with cement and sand. Waterproof your exterior walls before painting to prevent leaks. Hydroshield Dampproof by Nippon Paint is a fibre-reinforced waterproof coating that forms a thick elastic film that blocks water.

    The Dos and Don'ts of Waterproofing Basement Walls

    DO determine the source of the water.

    Wet streaks show where water is entering porous concrete. Look for streaks along cracks, at window corners, between mortar joints (for cement block walls), and around pipes where they enter or exit.

    If entire walls are wet, do more investigating. To test for condensation, dry a section of the wall with a rag and tape a square of aluminium foil to it. Check the foil's underside after 24 hours. If it's wet, outside water is seeping in. If dry, moisture is likely coming from a basement shower; instal a vent fan to direct steam outside.

    DON'T repair walls if the basement is flooded.

    During the rainy season, a crack in a basement wall can let in an inch or two of water. Before repairing the crack, drain the floor. Flooded basements increase the risk of electrocution. Turn off the basement's power and use a pump (with extension cords) to remove water. The pump will discharge water using a garden hose. Once the basement is dry, inspect, repair, and waterproof the walls.

    DO fill cracks with hydraulic cement.

    Basement wall cracks are also common. When a foundation is poured, its footing—a wide flat base made from concrete and steel—is poured first, then the walls. This is standard construction procedure, but it can create a "cold joint," a weak spot in the foundation between the wall and the footing where cracks can develop with foundation shifting and settling and soil pressure.

    Cracks can be sealed with hydraulic cement like QUIKRETE's Hydraulic Water-Stop Cement (available from Home Depot). Hydraulic cement is mixed with water to a putty consistency and then pressed into cracks with gloved fingers or a putty knife (follow mixing and application directions). As hydraulic cement expands, it seals cracks and crevices. Mix only what you can use in three minutes because it sets quickly.

    DON'T forget to address window well leaks.

    Window wells can cause basement wall leaks if a drainage system wasn't installed when the house was built. This can cause water to pool around a basement window and leak in.

    While it's difficult to instal a window well drainage system later, consider digging two feet lower in the well and filling it with gravel to help rainwater disperse rather than collect. Then caulk the window with GE's 100% Silicone Window and Door Caulk (available from Home Depot). Install a sloped window well cover, such as Shape Product's Universal Fit Polycarbonate Window Well Cover, to direct rainwater away.

    Best waterproofing company? Done! You're covered by Hitch Property Constructions.

    DO waterproof bare basement walls.

    If your foil test showed that water is soaking through your basement walls, seal the interior with DRYLOK White Extreme Waterproofer (available from Home Depot). Premixed sealant applies like paint. Brush or roll it on thick enough to fill all the surface holes before applying a second coat to waterproof basement walls. When dry, the sealant forms a watertight bond to prevent leaks. One gallon covers 500 square feet.

    Seal painted walls or efflorescence.

    If you or a previous owner painted the basement walls, you'd have to remove it before sealing, which only sticks to bare masonry. Older homes often have multiple layers of paint that must be removed by sandblasting contractors. Wire brushing is a tedious but inexpensive alternative.

    Before applying sealer, remove efflorescence with muriatic acid (per manufacturer's instructions).

    DO prevent basement flooding.

    Wet basement walls can be easily fixed. Remove foundation plantings like bushes and flowerbeds that need watering and let water into the basement. Check and repair gutters and downspouts to direct water away from your home. A 2% slope away from the foundation is also recommended.

    Consider installing an exterior drain tile system. This is a last-ditch effort, costing $10,000 or more. Installing a perforated drain at the footing level requires excavating around the basement. A waterproof membrane is often installed on the outside of the basement wall, and the system requires a buried sump pump. A foundation contractor should do this to reduce basement water problems.

    DO consider interior drainage.

    Installing a drainage channel under the basement floor can also dry the walls. The drain is similar to the exterior drain tile described above, but it's located inside the basement walls. New walls are built inside the drain, so the original basement walls aren't visible. This job costs around $5,000 and requires a foundation contractor. When it's done, you'll have new, dry walls, and any remaining water will be pumped away.

    How do we stop water getting into walls?

    How to handle water in a wall?

    First, check into a detoxication centre for our alcoholic escapism to stop the DTs and bloodshot eyes.

    Try an ashram. Transcendental meditation teaches us to love all living things (including cats) and accept water issues in our lives.

    Shave and massage yourself.

    Now we can go home, apologise to the cat, hide the gin, and plan our wall.

    First, find the leak.

    Water flows downhill, so we start at the highest point.

    Top of wall open to elements or roof overhanging? If the roof isn't overhanging, look for cracks along the wall's top. Is the top waterproof? Concrete roof or parapet wall? Water may be getting in where the roof slab meets the wall or through the parapet wall.

    Leaks from cracked concrete roof gutters

    A very common problem in Bali is leaking concrete gutters. It is regarded here that it is very bad form to allow water from your roof to run off onto a neighbour's property or into a street. If a building is built right against the property line, and very many are, then usually a concrete gutter is built along the top of the wall to catch water from the roof and take it away. These concrete gutters have two basic problems:

    • Ground movement often results in cracks across the gutter which allow water into the wall. If the cracks are small, this can be fairly easy to fix. The gutter must first be cleaned thoroughly then waterproofed in the inside, and it is best to do the whole gutter while you are at it.
    • Wall gutters are often built with the outer wall higher than the inner wall so that if the gutter fills with water, it will overflow into your building either across the ceiling or down the inside of the wall. In Australia, roof gutters are made of plastic or aluminium and purposely have the outer side of the gutter lower than the inner side, so if they fill up, they will overflow outwards. To solve this problem first make sure that the drain pipe from the gutter is large enough to take the roof area it has to drain and that the outer side of the gutter has low points cut in it to provide overflow points. These should, of course, be lower than the inner side of the gutter. It is also a good idea to make sure that downpipes have a gap between the gutter and the ground so that water cannot back up in the pipe.

    Check the surfaces of the wall.

    After checking the wall's top, check its surface. Check it thoroughly. Is it outdoors? Wind can drive rain at steep angles against a wall in windy places. Roof overhangs on well-designed buildings keep rain off the walls. Roof overhangs keep sun off walls and cool rooms.

    Rain-exposed walls can be waterproofed to prevent water infiltration. We'll discuss wall cracks in a minute.

    A wall must breathe so water can evaporate if it gets in. Walls shouldn't be waterproofed inside and out. If so, you may have damp walls.

    Rising damp

    Last is rising damp. This is common in Bali, where damp-proof courses aren't installed, but it can be fixed. Like poaching an egg, you shouldn't trust inexperienced cooks. Cut a horizontal slit through the wall's bottom and length. This requires care, and you don't do it all at once. High-density cement fills the slit. This is a sloof and prevents water from rising inside the wall. Injecting silicone solutions, a dubious technique popular in Britain, isn't available here. They wouldn't work due to the porous batako walls.

    We have a huge range of waterproofing services Melbourne at Hitch Property Constructions that offers stress-free services for any water problem you got!

    Sealing the leaks

    We've identified the cause; now what? I do not recommend using a skim of high-density waterproofing cement. This waterproofing film can crack. On a sunny surface, excess heat will crack the concrete skim away from the wall below, allowing water to enter.

    My prefered treatment is brush-applied polymer paint. It's colourful. Local versions are cheaper, but I doubt they're as good. Cracks need special care because they may move. Raintite has a bandage-like membrane. Paint Raintite polymer on both sides of the crack, then saturate the bandage. The bandage stretches to maintain the waterproof film if the crack moves. Polymers hate water.

    In waterproofing, stop water from getting in, not out. Even experienced builders sometimes try to seal leaks from the inside. Water can travel far through a structure or saturate it, making finding the source difficult.

    FAQs About Wall Waterproofing

    Waterproofing is best done at the time of construction. Using high-quality liquid waterproofing compound in the starting stage with cement and sand can be effective. Otherwise, use a waterproof coating before painting your exterior walls to prevent water leakage.

    Check walls for faults: Waterproofing external walls is the best solution only if the walls become damp as a result of rainwater or moisture. Before shopping around for waterproofing products, it's important to eliminate any other causes of structural dampness.

    Epoxy paint

    Epoxy paint is a common waterproof paint for concrete as it is tougher than some of the other options, provides good adhesion to porous substrates, and is highly water resistant. It is important to use a breathable paint for cellar walls.

    Waterproof admixtures are used to create waterproof concrete. The admixtures reduce the chance of water ingress by reducing the permeability and drying shrinkage of concrete.

    The most common way to waterproof concrete is to use a liquid waterproofing product specifically designed for that purpose. Liquid waterproofing gel is a thick substance that turns into a rubber-like coating once applied to the outside of a concrete wall.

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