The quality and type of the wall or floor surface you'll be tiling over is a key factor that will determine the success of your finished job. Here’s what you need to know and how to tackle every different type of surface for success!
Floor Surface Types
Concrete floors should be sound, dry, clean, flat. Any holes or irregularities should be filled with a suitable levelling compound 24 hours before laying the tiles. If the floor is too uneven or has the wrong “fall” it can be built up, after being chipped, with a two to one fine clean washed sand and cement mixture with a bonding agent additive.
Remember while concrete is hard and strong, new concrete will shrink slightly over time, so it is best to use an underlay and adhesive to allow for this. Ensure you include expansion joints at any change of the substrate surface and above all existing construction joints, also allowing for movement at the tiling perimeter.
Our Hot Tip: Drying of concrete depends on the thickness of the slab and if polythene sheet is used under the slab or not. For best results, concrete must be allowed to cure for at least 28 days.
Our Hot Tip: Cement topping should be dried for 7 to 14 days. Some specialist adhesives are available if tiling must be done before this full curing period, these are specially made for early age concrete or screed. See your local Beaumont Tiles store for the right advice.
Yes, you can lay tiles over STRUCTAflor YELLOWtongue and timber floors but there are particular materials and steps to follow. Check with your local Beaumont Tiles store.
Due to the expansion and contraction of timber floorboards, it is never recommended to adhere ceramic tiles directly onto a timber floor. Untreated floors should first be primed. Apply a Ceramic Tile Underlay, fixed according to the manufacturer's instructions (such as 6mm Fibre Cement Sheet) or a flexible underlay system. Allow to dry fully before tiling.
Plywood can be used under floor tiles if it is fixed soundly and sealed. The minimum thickness should be 16mm and must comply with Australian Standards AS/NZS 2270 or AS/NZS 2271 if used in a wet area. There must be no flex in the plywood floor. A flexible membrane or cement sheeting may be fixed over the plywood according to the manufacturer's instructions. A flexible adhesive to allow for any potential movement will reduce any risk of tiles and grout cracking.
Internal Floor Area Preparation
Internal floor areas include all living areas, entry foyers, hallways and kitchens....any area that is not specifically designated a wet area that requires waterproofing before tiling. Most floor substrates are either:
Preparing An Internal Concrete Floor
The quality of all tiling is strongly influenced by the condition of the surface you tile over, so it's important to ensure that your floor is firm and structurally sound, level and clean of oil, grease, dust and debris before you start tiling.
If the concrete is new, it must be allowed to cure for at least 28 days before it's tiled over. The rule of thumb for concrete curing is generally 1 week for every 25mm of slab thickness. Remember while concrete is hard and strong, new concrete does shrink slightly over time so it is best to use an underlay, flexible adhesive and of course, incorporate movement joints into your tiling, to allow for this. Talk to your Beaumont store for the best product to suit your project.
If the concrete is steel-trowelled, it will need to be mechanically roughened (and then thoroughly cleaned) before tiling, otherwise, you will not get enough adhesion.
Any concrete release agents and curing compounds should be removed by mechanical means.
Any holes or irregularities should be filled with a suitable levelling compound 24 hours before laying the tiles. If the floor is too uneven or has the wrong “fall” it can be built up, after being chipped, with a 2:1 fine clean washed sand and cement mixture with a bonding agent additive. This building up is not easy and should only be done in cases where the surface is quite unsatisfactory. Concrete floors should be left with a wood float finish.
It is important to start with a flat floor, particularly when installing large tiles. Interior floors should have a maximum of 5mm variation across 3 metres. Where the underlying floor surfaces are not flat, a levelling compound may need to be applied before tiling.
For concrete with small hairline cracks under 1.5mm, apply a flexible underlay, decoupling mat or crack isolation membrane before tiling. We can help with a range of suitable products. For cracks in the concrete wider than 1.5mm and the best solution for your project, consult your local in-store experts.
Once all concrete, patching and levelling compounds are cured and dry, the next step is priming (if required) then tiling.
Our Hot Tip: Drying of concrete depends on the thickness of the slab and if polythene sheet is used under the slab or not. For best results, concrete must be allowed to cure for at least 28 days. Cement topping should be cured for 7 to 14 days.
Preparing An Internal Compressed Fibre-Cement Floor
When compressed fibre-cement sheeting is used as a floor substrate, the minimum thickness required is 15mm. When it is used as an underlay over another surface, the minimum thickness required is 6mm.
Compressed fibre-cement sheets are dense flat sheets of reinforced cement, and should be fixed according to the manufacturer's instructions. Most fibre cement sheets have a surface layer of dust which should be removed by using a damp sponge or cloth.
We recommend always priming compressed fibre cement sheets with a suitable primer before tiling. To minimise risk from movement, apply a flexible barrier coating with reinforcement mat over joints between the fibre-cement sheets. Ask your Beaumont store for their recommended primer and joint covering products. Once the primer is dry you are ready to waterproof.
External Floor Area Preparation
Whether you plan to install porcelain, ceramic tiles or natural stone to an outside area, there are a couple of important points to note about the substrate or base surface that the tile or stone will be laid on. While the substrate will be unseen in the finished project, the quality and thoroughness of your preparation will affect the finished quality and performance over time.
The substrate or base should be clean, solid and free of movement. An ideal substrate is a reinforced concrete slab with a minimum thickness of 75mm thick or 100mm thick if the surface is likely to encounter any vehicle traffic on a path or driveway. The concrete should sit over well compacted crushed rock. All concrete shrinks so any new concrete slab needs to be dry and fully cured (for a minimum of 28 days) before tiling commences.
Ensure any outdoor base has adequate movement joints built-in to allow for expansion and contraction and any structural movement in the substrate. Tiles should never cover any structural movement joints in the substrate; the joint must be carried through to the surface of the tiling. Other movement joints will be required in the tile or stone at a maximum of 4.5 metres apart. If tile or stone is to be laid against a pool edge or against the house or fixed structure, there must also be a movement joint at this point.
Wall Surface Preparation Types
Plasterboard is a very common indoor wall surface but is not suitable for tiling over. If you have absolutely no choice, make sure you use an appropriate waterproofer. Tiling over plasterboard involves adhering tiles to a paper surface, and although this will present little problem in dry areas, if the wallboard is subjected to moisture, it may deteriorate causing failure. If there is a risk of moisture being present, only use a suitable moisture-proof plasterboard product or one of the alternative surfaces listed. Plasterboard sheets should be a minimum of 10mm thick.
Our Hot Tip: Speak to your local team of experts at your nearest Beaumont Tiles store for advice on the best waterproofing solution that's compatible with your tile and adhesive.
Brickwork is a common wall surface to tile over. Before tiling, brickwork must be rendered to ensure a flat finish. The render must be cured for at least 7 days before tiling.
Cement render is typically made from a 3:1 or 4:1 sand and cement mix and might be very porous. Because of the high sand content, there may be a layer of sand on the surface that needs to be removed before tiling which is easily brushed off with a broom then wiped down with a wet cloth.
Set Plaster, or Gypsum, is a highly absorbent surface and must be primed first (avoid using cement-based adhesives). Start with lightly abrading the surface then remove the dust with a damp cloth before moving onto priming. If the set plaster is over brickwork, it should be replaced with a more suitable material before tiling.
Our Hot Tip: All cement render should be left to cure for at least 7 days. If you're unsure about how to prepare your surface, speak to your local team of experts at your nearest Beaumont Tiles store.
Compressed Fibre Cement Sheet
To be used as a substrate, Compressed Fibre Cement Sheet should have a minimum thickness of 15mm for floor tiling and 9mm for wall tiling to comply with Australian Standards. When used as a separating layer or flooring underlay, the minimum thickness of sheets is 6mm however in a heavy-duty or commercial application, 9mm thick sheets must be used as the underlay.
Follow the manufacturer's recommendations for installing fibre cement sheets and be sure to pay special attention to the treatment of joints. Most fibre cement sheets have a surface layer of dust which should be removed by using a damp sponge or cloth before priming and tiling.
Ensure that the surface is primed before tiling and is clean and dry. Examples of compressed fibre cement sheet include Hardiflex, Versilux, Villaboard, and CSR Board. All are suitable for indoor use, but only Hardiflex is suitable for outdoor use. Blue board is not a suitable substrate for tiling. The manufacturer's recommendations should be followed in all cases.
Tiling Over Existing Tiles
You definitely can tile on old tiles! It’s a fantastic way to save time and money on a reno.
As long as they are in decent condition with no loose, cracked or drummy^ tiles, many existing tiles can be laid over with new tiles. The existing tiles must be free from any dirt, dust, grease, oil or any other contaminating materials.
If the existing tiles are glazed, roughen the surface with mechanical means before laying tiling over them. Don’t forget to wear an appropriate mask or respirator, safety glasses, gloves and hearing protection when doing this.
^A ‘drummy’ tile is one that sounds hollow when you knock on it.
Our Hot Tip: Our DIY experts have created a super handy DIY guide that will be your best friend throughout your DIY journey - click here to download.
Why Tile Over Existing Tiles?
Tiling over existing tiles is a great way to update your bathroom (or any other room with tired old tiles) without the expense or hassle of having to rip up all your old tiles.
Especially if you’re DIY tiling, simply laying your new tiles on the old tiles is a lot easier than the hard labour of pulling up your existing ones. Not only that, it can be much cheaper too. For the DIYer, removing old tiles often means hiring specialist tools and machines and if you’re paying for a professional tiler, pulling up tiles very quickly adds to your labour costs.
While tiling over tiles is a great solution for old tiles, it’s no solution for an existing tile job with issues. You need to be working on a solid surface. If your old tiles are loose, drummy, lifting, uneven or badly damaged, they are better removed. Tiling on old and damaged tiles does not improve problems and it pays to start fresh when necessary.
The first and most important step in tiling over existing tiles is to check that you are working with a solid surface. Tap each tile and if you hear a hollow sounding one it will need to be removed. If there are only a small number of cracked or loose tiles, these can be removed using a hammer and chisel. Mechanically remove the old tile and adhesive back to the substrate and fill the area with an appropriate patching mortar, finishing flush with the surface of the surrounding tiles.
Removing Old Wall Tiles
If you decide to remove the old tiles, retiling onto the same plasterboard or compressed cement sheet underlay may appeal as the best solution as is possible, however, be prepared to remove and replace the underlying plasterboard or cement sheeting - especially if the old tiles do not come away easily.
We recommend replacing the underlying plasterboard or cement sheeting and starting fresh to ensure the longevity of your tiling job. A great factor in removing the old plasterboard or cement sheeting is that you can easily remove large sections, taking less time and not worrying about damaging the old substrate.
How To Waterproof
Our DIY tiler runs through how to waterproof in our handy YouTube video.
How To Create A Shower Hob
If you're planning to build a new shower hob for your bathroom, after you prime but before you waterproof is the best time to do it. Follow the steps below to create your shower hob and check out our YouTube video.
Create And Prepare A Shower Hob
While 900x900mm is standard size for a shower hob, many people are opting for bigger or even double showers. Follow the steps below to create your shower hob.
Before you start building the hob, prepare the surfaces by applying a primer using a roller or sponge according to the manufacturer's instructions. Check with your local Beaumont Tiles store for the recommended primer.
- Start by measuring from the walls then out onto the floor, and create a line using a straight edge. Make sure the measurements are parallel and square to the walls. To check you have got it square, measure from corner to corner.
- Build the hob with hebel blocks. You can pick these up from most Beaumont Tile stores. Cut the hebel in half with a handyman saw.
- Stick down the hebel blocks with the cement screed recommended when you purchase the hebel. Create a sloppy mix and add it along the lines that were drawn earlier, pushing the hebel down into the cement. Add cement on the ends of the hebel blocks to bind them together. Once this is done, check the levels and remove any excess cement before it dries.
- In a shower, it is necessary to grade the floor to the waste outlet. The simplest method is to lay a mortar bed and build your gradient or fall into this topping. Before you make the cement screed for the shower base, it's important to mark the fall towards the grate drain on the wall. Australian standard AS3740 recommends that the gradient of a shower floor towards the drain is between 1:60 to 1:80 depending on whether there is a hob or a shower screen. A 1:60 gradient is 10mm fall every 600mm. You can cut wedges matching the required fall to the drain to temporarily place in the shower base to make levelling easier.
- By using a mortar bed, there is plenty of time to screed off a smooth, even fall towards the waste outlets. Mix your mortar 3:1 sand/cement. Pre-mixed sand and cement screed is also available. This topping mix should be a firm consistency, so it will retain its shape when squeezed in your hand.
- Temporarily block the drain hole to prevent screed from falling in. Mix the screed in a wheelbarrow or tip the mix into the shower area and create a well. Pour in the water and mix. Keep adding screed to the base until it is full, and use a level to even out the surface. Spread the mix over the shower floor and compact it. Then screed to achieve 20-35mm thick coverage.
When laying a mortar bed over suspended floors of fibre cement sheeting or structural particle board, it is a good idea to incorporate an expanded galvanised mesh in the mortar bed. This helps prevent cracks from appearing in the mortar bed. Don’t forget to ensure the screed lines up with the marks of the fall that were created earlier or finish to the height of the temporary wedges.
- Carefully remove the temporary drain cover and temporary wedges before the screed dries. When the screed is dry, fill any gaps left by the levelling wedges with more screed, finished flush with the surrounding surface.
- Once the completed screed is fully dry, sweep the area, and prime it once more with a suitable primer before waterproofing.
- Use a Neutral Cure Silicone Sealer in all of the internal corners of the shower including the walls, the floor and around the hebel blocks forming the hob. This will act as a bond breaker under the waterproof membrane.
- When the mortar bed has cured, apply your waterproofing membrane according to the instructions then, when it's dry, you’re ready to tile!
Our Hot Tip: Don’t forget to run your silicone “bond breaker” around all corners before applying the waterproof membrane.
Our Hot Tip: Our DIY experts have created a super handy DIY guide that will be your best friend throughout your DIY journey - click here to download.