FAQs

FAQs

Find answers to some common questions asked by our customers. If you can’t find what you are looking for please Contact Us.

  • Primers & Acoustic

    What is a primer?

    Primers are an important component in tiling as they improve the bonding of the tiling system, as well as improving the working characteristics of an adhesive. Inadequate or incorrect surface preparation is the most common cause of failure when bonding tiles onto surfaces.

    What are the benefits of using a primer?

    Good primers regulate the absorption rate of tiled surfaces. This results in:

    • Better water retention leading to longer curing and therefore higher ultimate strength. Adhesives that dry too quickly never gain full strength and can become brittle
    • Increased open time for the adhesive which means more adhesive can be spread and more tiles can be laid

    Other benefits of primers include:

    • A significant improvement in the bond of tile adhesives. Primers penetrate into the bare surface further than adhesives and also seal any difficult to remove dust
    • An increase in the adjustment time of tiles after they have been placed on the wet adhesive. So if a tile is out of line you have more time to adjust it
    • An increase in re-flow times for floor levellers
    • A reduction in pin holing in waterproofing membranes

    Do I need to use a primer?

    Yes, with the exception of substrates covered with a waterproofing membrane due to its non-absorbent nature. We recommend the use of a primer on all other substrates to be tiled. By not using a primer, you can void your product and tiling system warranties.

    What is the effect of high temperatures on primers?

    With high temperatures, primers can evaporate very quickly (known as “flash drying”) before they have penetrated the pores of the material to control porosity and trap embedded contaminants.

  • Effloresence

    What is efflorescence?

    Efflorescence is a concentration of salts (calcium hydroxide) present in all cements and other mortar constituents such as sand aggregates and lime which move through grout joints to the surface. Once this concentration reaches the surface, it reacts with the carbon dioxide in the air forming “Calcium Carbonate”. This then dries leaving behind white crystals which discolour the grout.

    Efflorescence is more prominent in winter months as the weather is colder and moisture more prevalent. It is more noticeable on darker grouts due to the colour contrast.

    How can I contain or reduce efflorescence?

    The key is to avoid excess water throughout your tile installation system. You should use fast setting adhesives such as 1 Part Rapid or 2 Part Rapid and use a low efflorescence grout such as Elite ColourGrout. Be sure to reduce the amount of water used in clean-up and avoid early clean-up of grouting. Allow grout to set fully for 24 hours prior to cleaning grout haze.

  • Waterproofing

    What are suitable substrates for waterproofing?

    The most common substrates are concrete and screed. Other suitable substrates for waterproofing include fibre cement sheet, wet area plasterboard, composite timber sheets, structural plywood, concrete, blockwork, render and existing tiles.

    Should I use a primer prior to applying a waterproofing membrane?

    Yes. Priming is vital prior to the application of all waterproofing membranes. The benefits of using a primer include increased adhesion of the waterproofing membrane to the substrate, assistance in decreasing pin holing and blistering and sealing of fine dust particles to the substrate. We recommend the use of PrimeX over non-porous substrates and Ultraprime over porous substrates.

    What is a waterproofing bond breaker?

    A waterproofing bond breaker is designed to allow normal building movement to be accommodated by a waterproofing membrane. Bond breakers allow the membrane to stretch, rather than snap, taking advantage of the elastic property of the material.

    Do I need to use a waterproofing bond breaker in my waterproofing system?

    Yes. To conform to the Australian Standards for waterproofing, a bond breaker must be installed in all internal corners, joints and movement areas.

    What areas require waterproofing?

    Internal wet areas such as shower recesses, toilets and laundries, external wet areas such as roofs, decks and balconies and other applications such as planter boxes, water tanks, ponds, retaining walls and swimming pools and spas.

    What type of tile adhesive should I use over a waterproofing membrane?

    Davco recommends the use of a flexible cement based tile adhesive over a waterproofing membrane. Unlike a premixed tile adhesive, cement based adhesives dry by a chemical process called hydration meaning that they cure over a membrane.

    What could cause my waterproofing system to fail?

    Common causes of waterproofing system failures include:

    • Poor bathroom design
    • Incorrect application of waterproofing system components
    • Incorrect positioning and installation of the shower screen
    • Water stops for hobless showers being too low
    • No priming before waterproofing membrane application
    • Incorrect selection, installation or lack of a bond breaker
    • Incorrect bond breaker size for membrane classification
    • Sealant incompatible with waterproofing membrane
    • Waterproofing membrane and tile adhesive not compatible
  • Adhesives & Sealants

    What is a tile adhesive?

    By definition, a tile adhesive is used for bonding tiles onto a surface. Additives can also be used to improve the performance of adhesives. A tile adhesive can either be cement based or a pre-mixed paste. The adhesive required for a tiling project will depend upon the surface, substrate, type of tiles to be used, area and conditions of the installation, such as temperature and humidity.

    What type of tile adhesive should I use for stack stone?

    For heavy stones, we recommend SE-7 mixed with Davelastic.

    Can I tile over tiles and if so what adhesive should I use?

    Yes. We recommend using Ultrabond primer as a first underlay then when cured an application of a flexible cement based adhesive or SMP Evo without any primer. In wet area applications, Davelastic should be mixed with the tile adhesive.

    Can I tile directly over brickwork and if so what adhesive should I use?

    No. We recommend rendering with an acrylic modified render which is then primed with PrimeX. SMP Evo tile adhesive is then used after 24 hours curing. SE-7 or Powder Mastic can also be used however the cement must have cured for 7 days prior to application of the adhesive.

    What adhesives are suitable for tiling over villa board?

    Villa board is a flexible substrate. After priming, we recommend using SMP Evo, Powder Mastic or SE-7 on flexible substrates.

    Can I tile directly onto a timber floor?

    No. We do not recommend tiling directly. Apply 6mm thick ceramic tile underlay prior to tiling onto a timber floor.

    What is the effect of high temperatures on cement based adhesives?

    The higher the temperature, the faster the cement particles react with water. When accelerated by temperature, and not by special ingredients in the formulation, the cement crystals which form are much smaller and therefore bonding is much weaker.

    What is the effect of low humidity on cement based adhesives?

    The presence of water is required to react with cement crystals. If the water evaporates from the adhesive before the particles have reacted the bonding will be weaker.

    What is the effect of high temperatures and low humidity on cement based adhesives?

    The result of these two factors is a considerable reduction in pot life, open time and adjustment time.

  • Grouts

    What is Epoxy Grout?

    Epoxy Grout is specially formulated for commercial applications where chemical resistance is required. Commercial areas such as dairies, breweries, food processing plants, hospitals, public toilets, commercial kitchens and laundries all require the use of an epoxy grout in tiling installations.

  • Enhancers & Additives

    What is an adhesive or grout additive?

    The main purpose of an additive is to primarily enhance the performance of the product. Cement based adhesives and grouts can be mixed with an additive.

    Depending on the characteristic design of the additive, the tile adhesive and/or grout can improve its performance by:

    • Increasing shear bond strength
    • Increasing or adding flexural strength
    • Increasing water resistance
    • Improving stain and chemical resistance
  • Other FAQs

    Does Davco have products for tiling my pool and pool area?

    Yes. When tiling your pools and pool area, a primer, waterproofing membrane, tile adhesive and grout must be used that are suitable for submerged areas. We recommend the use of PrimeX or Ultraprime primer, Dampfast waterproofing membrane, SMP Evo tile adhesive and Sanitized® Colorgrout or Elite ColourGrout mixed with 4 in 1 Grout Additive.

    Should I undertake a tiling project if the temperature is above 35oC?

    In extreme conditions with air temperature above 35oC, we recommend postponing the tiling installation until favourable conditions exist. Both temperature and humidity can affect the workability and performance of materials.

    What could cause my tiling project to fail?

    Common causes of tile installation failures include incorrect surface preparation and incorrect application techniques. Incorrect surface preparation may include tiling over an uneven, cracked, non-porous, or contaminated substrate.

    Incorrect application techniques include insufficient adhesive coverage and an excess of water that leads to the presence of efflorescence.

    Remember to always avoid short cuts in the tile installation process as rectification is far more costly than any potential savings.