Balcony Floor

How do you waterproof a balcony floor?

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.

Many balcony areas and terraces are created above living spaces, whether on a flat roof above an extension of living space, kitchen or bedroom or the top floor of an apartment complex.

Great attention needs to be given to sealing the balcony surface and waterproofing it.

In the realisation of waterproofing systems for balconies or terraces, it’s important the ability to know how to evaluate and consequently choose the waterproofing system best suited to the existing situation regardless of whether it’s new construction or the adjustment of a pre-existing situation; it’s. Therefore, necessary realise it to perfection, paying particular attention to all types of details and to the accurate treatment of them, which in most cases represent the critical points from which water leaks occur causing the subsequent problems.

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

An essential part of the building works.

Balcony waterproofing is needed for preserving your any area underneath the balcony from any perennial water ingression damage. In areas susceptible to snow or frequent rainfall waterproofing the balcony surfaces is an essential part of the building works and cannot be taken light-heartedly.

A recent statistical survey has shown that “Balcony Waterproofing” has the highest failure rate of all the areas in the building envelope. 

Whereas a mere 1.8% of the total cost of the build is spent on waterproofing balcony areas, these account for a staggering 83% of building defect complaints.

Sealing flat roof balcony areas, balconies on top of rooms and terrace areas waterproofing should be a well thought out process and applied correctly from the outset; the consequences can otherwise be severe.

Balcony Floor

Keeping a balcony safe from water

There are lots of new technologies and materials available, but also different methods are available that can keep your balcony safe from water. Balcony surfaces are made using concrete or timber roof with a layer of waterproof material that covers and guard that substance. Concrete structures face different issues than timber or steel construction, and materials for one may not suit the other. Many a time, you may face the problem of repairing your balcony surface over and over again if you have not used a proper system or the waterproofing was performed in a poor way.

Accumulation of calcium crystals and salts that disfigures the top edges or underside of masonry is known as “Efflorescence”, and this cannot form in the absence of water. The material chosen should have the correct amount of expansion capabilities as the materials around them, and they must be able to adhere to them and create a good bond and seal.

The correct sequence of works

Penetrative work and fixing down must be performed prior to water sealing and waterproofing. If you are erecting a balustrade in these areas, you will probably be required to have baluster posts that need to fix down to the structural elements of the building. In cases such as these, the sealant or balcony waterproofing material must be able to seal around these and remain bonded to the steel of the balustrade posts. Choosing a brittle substance will not be good as the steel will expand more than the substance, and a leak could arise at that point.

Very good materials for this sealing between two different materials are the polyurethane-based sealants such as Sika flex 11FC. These materials have extraordinary strong bonding capabilities, are able to bond to different materials (stone, steel, glass, rubber etc.), have very high and low-temperature resistance and are resistant to UV which is very good if the area is exposed to sunlight.

When fixing any material to a finished roof, one must be very conscious of water ingression and must seal properly with proper materials.

What to do before waterproofing a balcony or a terrace

In order to waterproof a balcony or a terrace, first of all, it’s necessary to evaluate the existing conditions of the area to be treated because, depending on the state of conservation of the balcony or terrace on which you want to intervene, there are different solutions and different steps to follow, more or less invasive to restore or to do a new waterproofing system.

The first thing to evaluate is the state of the existing flooring, that is the visible layer, which is also the easiest to investigate regarding its state of conservation. This evaluation can be carried out, for example, by checking if the volumes of the joints are consistent or missing because in most cases it’s from the joints that the water starts to infiltrate and therefore the waterproofing effect of the finish is missing.

Consequently, the water will begin to deteriorate the whole pack, with serious damage to the elements. In parallel, it’s possible to check the status of the elements of the flooring even if these are for outdoor and therefore waterproofing, any cracks or breakages of the same provide access to water creating infiltration points.

MULTIPANEL Waterproof Balcony System

MULTIPANEL manufactures a revolutionary, high-density, polyurethane composite building panel, ideal for waterproofing balconies as it is the first panel of its kind in the market that is truly 100% waterproof.

100% Waterproof

Many other panels are water-resistant and hence rely on the need for a liquid membrane to waterproof a project. With MULTIPANEL, you have peace of mind knowing that the panel is immune to water and will act as a complete water barrier in all wet area situations.

Super Lightweight

MULTIPANEL is up to 80% lighter than traditional products. 30mm MULTI PANEL weighs only 18Kg per sheet (6.25Kg/m2)

Labour Saving

All edges of the panel are tongue and groove for installation convenience. As MULTIPANEL is so lightweight and can be used without a liquid membrane, MULTIPANEL can be installed up to 75% faster than alternative balcony systems.

Eco Friendly

EcoSpecifier has independently verified MULTIPANEL as an environmentally friendly material. MULTIPANEL offers significant insulation advantages which offer increased savings for the total life of the project. There is also no material wastage as offcuts can be joined together using MULTIPANEL Polyurethane adhesive with joins becoming stronger than the panel itself. MULTIPANEL can also be joined off a floor joist, helping to minimise wastage.

Where is it used?

As an external substrate for tiled residential balconies and decks, it’s an alternative to particleboard, plywood or compressed fibre cement.

Balcony Waterproofing

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.

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

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 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.

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.

Steps to waterproof a balcony or a terrace

First of all, it’s necessary to distinguish whether it’s necessary to carry out waterproofing again or if we are talking about the restoration of an already existing waterproofing system of a balcony or terrace. This evaluation allows us to understand at what level of the waterproofing package we need to intervene.

While in the first case, the realisation of the waterproofing system is simpler, in the case of reconstruction, it’s necessary to proceed first of all with the analysis of the existing situation. In the second case, it’s possible to perform an operation modality which provides a minimally invasive treatment which initially consists in removing any efflorescence, deposits or previous treatments such as waxes, and then cleaning the support with a neutral detergent. After drying, the grouting of the terrace can be remade with a suitable outdoor putty, which will therefore have excellent impermeability characteristics which will allow the integrity of the finishing layer and consequently of the entire package reconstructed. To conclude we will proceed with some treatments that in most cases are transparent and no-film products, which allow for waterproofing in bulk, especially for the points of greatest risk as are the joints, to ensure that after the intervention is restored the waterproofing of the last layer of the balcony or terrace.

From the moment in which, surely, the water is infiltrating the finishing layer, we proceed to restore the waterproofing system of the terrace in another way, that is to remove the irreparably compromised existing flooring, together with the layer of glue and the waterproof layer that protects the screen.

From here we will provide a new waterproofing of the screed with waterproof liquid products and the subsequent bonding of the new coating, with a cementitious adhesive suitable for the type of substrate and grout with waterproofing characteristics specially designed for outdoor use.

How to avoid leaks on the balcony or terrace

Always pay attention to choose the correct size of the joints and the material with which make them according to the type of flooring you want to apply on your balcony or terrace.

For example floors with generously sized tiles have been used more and more often, so that the joints must be proportioned to that, so the friction does not create subsequent cracks in the flooring and risks of infiltration.

Another element to pay particular attention to are the thresholds, namely the connection between balcony or terrace and the window-door that links it inside the house; it’s a good rule that these are at least 1 inch higher than the walkway of the balcony even if more and more often, for aesthetic reasons, are made at the same level of the floor, so the rainwater disposal function is only given to the slope of the package.

With regard to the treatment of details such as wall-floor corners, expansion joints or drains, special preformed elements are usually created to be used with the various waterproofing systems proposed and may be butyl tapes, gauze or strips that provide additional waterproofing in those points where the risk of leaks is always greater due to their particular complexity of geometric conformation.

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

Characteristics of the ideal product to waterproof a balcony or terrace

The ideal system for waterproofing a balcony or a terrace must provide a waterproofing layer that is elastic and extremely tough while ensuring extraordinary adhesion to the cement bond that will be used for applying the flooring. It will be simple to apply as the components specifically studied to treat the details (such as wall to floor corners and drains).

The technical documentation of these systems must have characteristics that comply with the regulations in force for its intended use.

Whatever the problem, if the waterproofing system has failed, it is recommended that the tiles be removed in order to start the waterproofing and tiling process from scratch. While it is possible to waterproof and tile over existing tiles – provided the existing tiles are in good condition and firmly attached to the substrate – where tiles are cracked, loose or hollow sounding, or where the level of the current floor does not allow for a height increase, tiles will need to be removed and replace.

A waterproofing membrane is essential to keeping your outdoor area in prime condition – think of it as a raincoat for your balcony. You don’t like being wet, you hate damp clothes, and the smell of mildew doesn’t scream homely and comfortable, so tackling balcony leaks as soon as possible will make your days (and nights) a whole lot sweeter.

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