My Balcony

How can I waterproof my balcony?

Balcony leaks are common, particularly in older homes, and if left unchecked can lead to extensive damage. It’s worth remembering too that termites are attracted to damp areas, and fungal growth around the home and a termite infestation is one headache you don’t need. If your balcony is leaking, it is important to take steps to rectify the problem before it causes wider issues. Balcony waterproofing doesn’t have to involve major renovations; with a balcony sealant you can have a tight water balcony within a day and at a much lower cost than taking up the tiles, replacing the waterproof membrane…or paying thousands to rectify termite damage in the future.

Check out Hitch Property Constructions for a wide range of balcony repairs.

How to Waterproof Decks and Balconies

Firstly it is important to look at the location of the deck. In some cases the deck will be buried, and in others, it will be exposed, and so subject to wear and weathering, and so the right products must be specified to suit the end use of the deck. Balconies will usually be above ground so the product choice will often be more straightforward.

My Balcony

How to Decide Which Products to Use

Deck and balcony waterproofing products should have a very good bond to the substrate they are applied to, and this is especially the case where the deck is exposed and subject to wear and weathering, where the deck waterproofing materials will also need to be slip-resistant and able to deal with UV also.

Newton offers a wide range of products for waterproofing concrete decks, that cover all end uses, including vapour permeable and vapour impermeable options as well as a selection of primers, wearing coats, multi-coat systems and drainage membranes. The product or products selected for the project are very much dependent on the intended use, and on the location of the area – for example, if a deck is exposed to the elements then the product selection would be different to a scenario where the deck is covered.

Newton’s technical experts can help design a solution which is right for your project.

What to consider before waterproofing

In new construction, the designer decides the best waterproofing solution for outdoor flooring. A Best Practice which has become commonplace is that of applying a drainage membrane on the underside of the substrate, serving as support for correct waterproofing. UNI11493-1 regulations, in fact, state that “the indication of a drainage and protection membrane, applied between the substrate and water barrier, is a measure with the objective of preventing water stagnation from penetrating the structure.”

On the other hand, in renovations, it’s important to evaluate different factors in order to choose the best solution based on certain basic conditions.

In this case, the first thing to analyse is the area where the intervention will take place:

  • evaluate the state of conservation of the flooring and substrate
  • verify the layered section of the structure
  • make sure that the slope of the flooring is appropriate
  • check that there are no fractures or separation between the various layers

Depending on the conditions of the terrace or balcony in question, you can choose the best solution between those described below. 

Choose the most suitable waterproofing solution for renovations.

Based on the conditions of the terrace or balcony, you can choose the best solution by evaluating several factors. If the flooring is in perfect shape, it might be enough to directly waterproof the floor covering.

However, if there are issues with the tile, such as cracks or holes, it’s a good idea to remove them and waterproof the underlying layer, that is, the substrate. If the condition of the substrate is also inadequate, the best solution is then to waterproof the layer beneath the substrate, hence preventing any possible future infiltrations.

Waterproofing solutions without removing the tile

If the flooring is in good condition, without cracks or tenting, liquid waterproofing is a good solution to employ without having to remove the tiled surface. It is easy to use and can be applied quickly with rollers or brushes onto the entire surface without leaving gaps while creating a thickness of only a few millimetres. Such procedure, which should be carried out by carefully following the instructions indicated by liquid membrane manufacturers, is resistant to temperature changes, bad weather, chemical substances or stagnant water. A fundamental aspect to consider with the supplier is the suitability of the product the existing flooring.   

Waterproofing solutions between tile and substrate

If the flooring is damaged or unsuitable, it is necessary to remove it and intervene in the layer underneath completely, that is, on top of the substrate. Two main solutions stand out from what’s available on the market: waterproofing membrane rolls or waterproofing liquids.

Rolled membrane waterproofing systems

On the market, there are numerous solutions in which to use rolled membranes to waterproof the substrate. The most common are bituminous, rolled, self-adhesive waterproofing membranes that can be applied with hot air welding on site.

The substrate must be clean, dry and free of dust and debris. Subsequent to the application of the adhesive membranes, thinset can be spread for the tile application.

If the waterproof layer under the substrate is undamaged, you can implement a cleaner and faster solution, such as a polyethylene rolled membrane. In order to use this type of waterproofing, we suggest using Floortec, a membrane composed of a base in polyethylene laminated with non-woven fabric on the underside. With a total thickness of only 3 mm, Floortec not only reinforces the waterproofness of the substrate without substantially influencing the interior of the flooring, but it also compensates structural tension, manages moisture which rises through the installation and provides additional load resistance. Upon the installation of the membrane with cement adhesive, the tiles can be installed.

Cement-based liquid compound waterproofing system

An alternative to a bituminous membrane may be the application of a cement-based liquid layer that is easy to apply on top of the substrate. The product is a cement-based mixture to which polymers and other elements impervious to water are added. The tiles can then be applied over this layer with the appropriate tile adhesive. This procedure is simpler than the previous one. Still, the cement layer, in practice, is not perfectly waterproof and could dilate or shrink as a result of changes in temperature, allowing a small amount of humidity to pass to the layer underneath. This technique is recommended in interventions where there is no doubt that the substrate is in perfect condition and does not present cracks or hairline fissures.

Looking for balcony repairs Melbourne? Look no further. Hitch Property Constructions has you covered.

Waterproofing solutions under the substrate

The best solution to solve and prevent any infiltration and subsequent degradation is to intervene under the substrate. For optimal results, the procedure should include the application of a waterproofing layer, on top of which is applied a drainage membrane that provides protection and allows the outflow of water that percolates from the upper layer of the draining substrate, as suggested by regulation UNI11493-1.

Bituminous membrane waterproofing system

Bituminous membranes are the most popular system used to waterproof under the substrate of terraces and balconies. These membranes are derived from the distillation of crude oil and commercially sold in prefabricated rolls. In the thickness of the roll, there is also an armature (in glass-fibre or polyester-fibre) to increase resistance. In pedestrian areas, such as terraces and balconies, the application of a bituminous membrane with a thickness of 4 mm is recommended, in order to increase the mechanical resistance and maintain the elongation property that is characteristic of this material. The sheets of prefabricated rolls are easy to install and, due to flame bonding, guarantee complete adherence.

In application settings where an open flame is not permitted, the same membranes are available with an adhesive layer. These are easier to apply, yet provide slightly reduced effectiveness.

The importance of draining membranes

Draining membranes under the substrate are true lifesavers for the structure of the building.

The main cause for damage to terraces and balconies is, in fact, the presence of water when it inevitably infiltrates to the interior of the substrate and slowly wears the various waterproofing layers. The unique structure of the drainage membrane prevents this type of problem. For this reason, we recommend Draintec 8, a membrane designed by our technicians to allow water drainage through a series of drainage channels, compensating hydrostatic tension in contact with the substrate and the bitumen-based membrane. Its particular shape supports and decreases load compression resulting from pedestrian or load passage. With a thickness of only 8 mm, Draintec 8 contains two glued layers. The first is a base in polyethylene with cone-shaped elements used to separate and drain liquids. The second layer is in non-woven fabric which is laminated above the base, with the function of blocking the passage of small particles and debris so that these do not obstruct the channels and decrease the effectiveness of the membrane.

When using a draining substrate, we suggest installing Draintec 8S, composed of a net with a looser weaving structure than that of Draintec 8.

Using a perimeter profile for optimal results

To complete an intervention with state-of-the-art results, we suggest installing the Border Tex BD profile along the perimeter of the terrace or balcony. The purpose of this edge profile is to guarantee the complete drainage of water through specifically designed drainage holes. Bordertec BD should be positioned under the substrate, precisely between the drainage membrane and the bituminous membrane. Together with the Draintec 8 drainage membrane, it is the ideal product to protect the terrace structure from infiltration and deterioration.

Balcony Waterproofing

Balcony waterproofing is one of the most common failure points in domestic waterproofing alongside bathrooms, and both can be exceedingly expensive to fix. You only get one chance to get it right as fixing a problem at a later date requires removal of the trafficable surface – not the easiest thing to do where tiles are used.

Installing Butyl Rubber

As with any works, balcony waterproofing requires a well prepared, strong, and stable substrate. This substrate can vary from system to system, but a good rule of thumb is to provide a finish that you would be willing to tile to without the addition of any waterproofing.

The Waterproofers also request that no silicone or polyurethane is used on a balcony prior to us coming to apply the waterproof coating. We often find leak control flanges (floor wastes) have been fitted and edge sealed with silicone. This silicone can interfere with some systems and prevent us from performing our works. We understand that tradesmen want to try and achieve a watertight seal prior to leaving the site. Still, these actions can sometimes render it impossible for us to provide a warrantable solution.

Balcony waterproofing can be achieved using almost any of the product ranges we typically apply. Different systems have different benefits and some special considerations when evaluating which solution is best suited to your project. Get in touch with us if you would like us to help you work out which solution should be used. We do recommend you avoid the use of torch-on bitumen membranes on a balcony. Although they are classed as a trafficable membrane system, they do not take well to traffic on warm to hot days. Softened bitumen is easy to damage and can transfer to your shoes and become trampled through your house.

Butyl Rubber Waterproofing

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. In some cases, an epoxy primer is required prior to the laying of the butyl rubber waterproofing membrane.

When using butyl rubber waterproofing under a screed, you will still have to apply another waterproofing membrane to the screed once dried to avoid any moisture soaking the screed and/or efflorescence rising from the screed through the finished surface. This membrane can be another layer of butyl rubber or one of the many seamless liquid membranes available.

Another thing you should bear in mind when looking at using a butyl rubber is that it needs to be applied prior to the installation of door and window frames, and needs to be bonded to the building framework (or masonry) prior to the installation of any wall finishes. This is especially relevant with the rising use of lightweight foam construction and is evidenced by the leaky homes crisis in New Zealand, also known as “leaky building syndrome”.

The final major consideration for butyl rubber balcony waterproofing is the application of finish materials, be they tiles or other finishes. Butyl rubbers by their very nature are not easy materials to bond to, and as a result, most tile adhesives have serious problems creating an acceptable bond. It is best to discuss your finishing material with us when discussing your project.

Hitch Property Constructions has a wide range of the Melbourne balcony repairs right here. 

Seamless Liquid Waterproofing

Balcony waterproofing using a liquid system is slightly less forgiving than using a butyl rubber system but can be performed later in the construction phase minimising the opportunity for damage. The substrate should be prepared and ready to accept the finishing product, and in some cases, epoxy primers may have to be applied in place of the standard primers.

Unlike butyl rubber, balcony waterproofing using a liquid should have door frames and wall cladding in place. Flashings should be insecurely fastened behind the cladding and be well exposed onto the balcony floor where the membrane is not encapsulating the full wall.

Liquid waterproofing systems can also accept a wider range of adhesives when it comes to final finishes. Again, these should be discussed prior to work commencement to ensure compatible products are used.

There are also some liquid membrane systems for balcony waterproofing which provide both a watertight seal and a trafficable finish in a single system. These systems are especially useful where weight considerations are of extreme importance, or costs need to be contained.

When it comes to protecting your home, you might already know the importance of waterproofing your outdoor deck. Waterproofing decks protect the surface from water damage, including mould and dry rot. Something that you might not think about as much is waterproofing a balcony. Read on to find out the scoop on whether or not your balcony needs to be waterproofed.

The fact of the matter is that if you want to keep your home safe and the people you love safe, then getting your balcony waterproofed is essential, you can either go at it DIY-mode or ring up a contractor. This is especially true if your balcony is wood-framed as these balconies experience a higher rate of failure than others. Wood-framed balconies can experience leaks, visible damages as well as invisible damages. These invisible damages include structural damages from dry rot. Dry rot affects the integrity of the wood from the inside out. One way to spot dry rot is to press down on a piece of wood with your foot or hand. If the wood feels spongy and does not feel like a usual hard surface, this is a good indicator that dry rot is present.

If your balcony has a concrete structure, it doesn’t quite mean that you’re off the hook. Concrete structures need to be waterproofed as well. Waterproofing the concrete means that you’ll be giving the concrete an added level of protection. Waterproofing concrete also prevents cracks from forming, prevents mould and mildew and protects from UV rays. This is especially important as most balconies receive high amounts of direct UV rays. Another thing to consider is that when you waterproof your balcony, you’ll be saving money in the long run. Repairing a deck that has water damage will almost always be significantly more expensive than simply getting it waterproofed in the first place. If you have a balcony, be sure to talk to a professional about waterproofing.

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