Tiled balconies are a feature of many homes and strata units in WA. However, there are some critical elements that need to be checked during construction, warranty periods or purchase evaluations.
1 What are We Talking About?
Balconies are a common feature for a variety of styles of homes and strata units in WA. Given their exposure to the elements, many have ceramic or stone tile floor coverings.
Ultimately, rain/storm water will land on these balconies and this water needs to be directed off the balcony or into a drain. The water cannot be allowed to pond on the tiles.
2 Where are We Talking?
Balconies can be located on a ground floor of a home or unit which may or may not overhang the natural ground level or it could be on an upper floor or it could be 15 floors up on a multi-level apartment building. Balconies are literally everywhere and come in a variety of shapes and sizes.
3 How are They Made?
The majority of balconies these days are constructed usually via a suspended or cantilevered concrete slab. Given the durability of tile and stones finishes, most balcony floors are covered in ceramic or stone tile of some description. As with internal wet areas of a home or strata unit, the tile joints between these ceramic or stone tiles are generally filled with a grout. Given the concrete slab below the tile (which encases the strengthening steel) is a porous material, a waterproofing membrane must be laid beneath the tile covering so as to ensure water cannot not enter the concrete slab and penetrate the steel, which can cause the steel to rust and hence contribute to the development of concrete cancer.
4 Simple Really – There can’t be that Many Issues Then?
Sadly, there are a significant number of issues associated with the incorrect construction and or poor maintenance of balconies.
4.1 No Drains and Incorrect Falls
Given the importance of removing water from the floor of tiled balconies from both a health and safety perspective but also the need to ensure water does not pond on the balcony, it is important that the balcony floor levels fall away from the building off the balcony or toward floor drains so as to remove water. It is surprising how many balconies and balcony passage ways are constructed without floor drains and or the fall of the installed tiles is actually toward the building and not toward the balcony edge or drain.
4.1.1 The floor tiling in the example below falls towards the apartment and not towards the floor wastes.
4.2 No Fall to Drains
Having drains is one thing, ensuring water flows toward those drains is another! There are very specific requirements in relation to the required floor level falls on tiled surfaces to direct water off the balcony or into the installed drains. Sadly, we come across a large number of balconies where there is little or no fall in floor tiles toward installed drains. Where water does not fall toward drains, the potential is that the water will pond on the balcony surface. Apart from being a safety issue the water may start to permeate the grout toward the slab.
4.3 Insufficient Fall to Drains
There is insufficient fall to the floor tiles towards the floor wastes, the minimum fall required is 1 to 100 (1%), the fall as measured on site ranges between 0 % and 0.4 %.
4.4 Lack of Puddle Flanges to Floor Drains
Even if there is a floor drain and the correct fall in the floors toward those drains, that does not mean the actual drain has been installed correctly. One of the key elements of a floor drain is to ensure that puddle flanges have been correctly installed.
4.4.1 There is no puddle flange installed at the junction to the floor wastes and the storm water inlet as required and the pipework is approximately 65 mm below the floor waste inlet.
4.5 Lack of Flexible Sealant to Joints
Given that walls and floors can expand and contract at different rates during temperature changes it is important that joins at this critical junction have an extra layer of protection through the application of flexible sealant at the joint.
4.5.1 There is no flexible sealant joint at the junction between the floor tiles and the skirting wall tiles as required.
5 Intermediate Movement Joints
In larger areas of balconies where the expansion of the slab and tiles can be more extensive during the summer months, it is important that expansion joints (think railway tracks) are installed so as to ensure cracking to the protective tile cover can be avoided.
5.1.1 There are not sufficient intermediate movement joints to the floor tiles as required.
5.2 Balcony Penetrations
The area below the balcony was checked for signs of moisture ingress through the suspended concrete slab balcony specifically at the area around the gutter downpipe waste area. There was cracking and moisture with a high reading on a moisture meter detected to gutter downpipe waste area.
5.3 What is All the Fuss About? – Failure or Lack of Waterproofing Barriers!
If water manages to seep between the tiles or through cracks in the tiles the waterproofing membrane is designed to protect the slab from water ingress and the potential onset of concrete cancer.
Once again, we come across a large number of balconies where there is no waterproofing barrier or that barrier is defective and water that manages to escape the tiles and or grout will start to seep through the concrete slab through to the floor below.
When steel rusts it can expand up to six times its original size with such force that it can crack concrete!
6 Solving the Issue
Prevention is the absolute best solution hands down! When a balcony is constructed, home owners and strata companies must ensure that the key elements mentioned above are all correctly installed.
If there are any signs of water ingress then this should be tackled as earliest as possible. The two most common options include:
- Re grout, reseal, repair cracks and fill all sources of water ingress
- Lift the tiles and relay the waterproofing membrane and retile
- Where balconies are not tiled but is simply bare concrete, it is important to regularly paint the balcony with a trafficable water proofing paint so as to seal any cracks and ensure that the underlying concrete remains waterproof
The above can be seen as extreme until you understand the challenges which can be associated with resolving concrete cancer in a balcony:
- Scaffold the area/building
- Remove tiles and waterproofing
- Remove concrete down to steel (both sides of balcony) as required
- Treat and or replace steel and replace concrete
- Check and address as required- floor falls, drains, expansion joints, etc.
- Reapply waterproofing membrane and tiles
- Pay a substantial invoice!
7 Building a New Home
For people building a new home or unit with a balcony it is important to ensure that a complete waterproofing barrier is installed prior to any balcony tiles being laid. All of the key components of the balcony mentioned above must be installed as per Australian Standards
8 Buying an Existing Home
People buying an existing home with a balcony should pay particular attention to water ingress on the undersides of balconies and or any signs of rust or concrete cancer. Impacts of concrete cancer should be factored into buying decisions.
9 Buying a Strata Lot/Apartment
The situation with strata Lots tends to be more complicated as it will often relate to where the boundary between Lot property and Common property lies. Often with strata balconies, the upper surface of the floor (tile) tends to be Lot property and the area below the tile to the surface above the ceiling on the unit below is common property. Often, water ingress between balconies and the resultant damage will often involve the Strata Company. None the less it is important that all of the stakeholders in a strata Lot carefully monitor balcony issues particularly those involving water ingress.
10 Summary
10.1 The Australian lifestyle is conducive to the construction and use of balconies.
10.2 Balconies are generally exposed to the elements. Rainwater ponding on balconies can permeate the tiles and enter the porous concrete slab. It is critical that water not be allowed to pond on balconies. Water must be able to run off balconies or into balcony drains.
10.3 There is a broad array of Australian Building Code requirements and Australian Standards directly related to the correct construction of balconies and the associated waterproofing.
10.4 Water ingress into a balcony needs to be addressed quickly and substantively. It will not get better on its own!
10.5 If water ingress into a slab is not addressed and concrete cancer develops it can be fixed. But, it’s expensive.
If you are building, buying, managing or maintaining a property in WA with balconies and you need advice or support from a Building Inspector who is a WA Registered Builder with a minimum of 20 years’ experience, then contact Houspect WA.
Build, Buy, Invest in Property with Confidence
Ph 9240 8855 Web: www.houspect.com.au/wa Email: enquiry@houspectwa.com.au
