Tips for sealing a shower tray

Poor application or failure of silicone sealant is by far the most common cause of water leaks from shower trays and enclosures. Here are some handy tips to help you apply silicone sealant correctly and achieve a professional finish.

Get the right tools for the job

  • Purchase a good quality sanitary silicone sealant that is intended for use in bathrooms and contains an anti-fungal additive.
  • Select the correct type of silicone sealant.  If you have used natural stone for wall or floor coverings it will be necessary to select a sealant that is compatible for use with the type of stone.  Consult the supplier or sealant manufacturer for guidance.
  • Purchase a good quality sealant application gun.  This will help you to apply the silicone sealant evenly and achieve a consistent bead that will be easier to smooth to a perfect finish. 
  • Purchase a silicone sealant application tool.  These handy tools are made from rubber and are designed to remove excess sealant, leaving a neat and consistent bead of silicone.  The tool pictured on the right is called a Fugi, produced by Cramer it has various sized cut outs designed to produce differing bead thicknesses and is suitable for use with silicone sealant and caulking although similar tools can be purchased from tile retailers and good DIY outlets.
  • Paper towels and a large plastic bag.  When smoothing the freshly applied silicone sealant it will be necessary to clean excess from the application tool with paper towel.  Silicone sealant is very sticky, after cleaning the application tool dispose of the paper towel and make sure that your hands are clean and free of silicone sealant.  

Preparation is the most important aspect of applying silicone sealant

  • Always read and follow the silicone sealant manufacturer’s instructions.  This very important as the sealant must be fully cured before it comes into contact with water.
  • The area to which silicone sealant is to be applied must be clean and dry. 
  • Use a vacuum to remove loose deposits and surface dust then thoroughly clean the shower tray surface and tiles in the area where to sealant is to be applied with a damp cloth that has been soaked in a mixture of warm water and mild detergent to remove any grease and stubborn deposits, do not get the area wet. 
  • Once thoroughly clean wipe down the area with a clean damp cloth to remove any detergent, again do not get the area wet.
  • Thoroughly dry the area with paper towel.  If any moisture remains the silicone sealant may not fully adhere to the surface.  It may be necessary to allow the shower tray to air dry for a couple of hours before applying the silicone sealant.

Applying the silicone sealant carefully and follow the manufacturer’s instructions

  • Ensure that the shower tray and walls are completely dry and free from any dust, grease and debris.
  • If you are using a tool to smooth the silicone sealant, such as a Fugi, select the correct aperture size to produce a finished bead that will completely cover the gap between the shower tray and tiles.
  • Cut the application nozzle on the silicone sealant tube at a 45 degree angle and ensure that the hole is not too big.  The nozzle will often have performed marks indicating where and how to trim the nozzle.  A 5mm hole in the end application tube will normally be sufficient for most applications however this may need to be enlarged if a wider bead is required.
  • Begin by applying the silicone sealant to the inner corner of the shower tray.  Apply gently pressure to the trigger of the application gun and work towards the front of the shower tray in one continuous and smooth action ensuring that a uniform bead of silicone is applied.
  • Try not to apply too much sealant as it will be difficult to remove.
  • Ensure that the bead of silicone sealant is thick enough so that it completely covers the gap between the shower tray and the tiles and that there are no visible gaps.  If there are any gaps do not worry, carefully add a little more sealant to these areas if required.
  • Once you have finished each line of sealant be sure to release the pressure from the application gun or the sealant will continue to flow from the nozzle. Wipe away the excess sealant from the nozzle and replace the cap.  Some residual pressure can remain in the tube and silicone sealant can leak from the nozzle onto clothes or floor coverings which can be very difficult to remove.  Take care.
  • Staring from the point at which the silicone was first applied place the silicone sealant smoothing tool against the shower tray and tiles.  Apply gentle but consistent pressure and drawer the tool along the length of the shower tray to remove the excess silicone, leaving a neat and uniform bead. 
  • Once a smooth bead has been achieved do not be tempted to keep smoothing the silicone as it will start to tear, become untidy and may not adhere correctly.
  • Allow to cure fully.  Fresh silicone should be left to dry or cure completely, normally for a minimum of 24 hours, although this can differ for each brand or type of sealant and it is therefore important to read and follow the manufacturer’s instructions carefully.

For professional shower tray or shower enclosure installation services in London, Surrey, Sussex, Kent and Dorset please do contact our shower enclosure and wetroom experts.

Contact our Dorset bathroom shower design team on 01929 551963 or

Contact our Surrey bathroom shower design team on 0208 393 3888 or

Thoroughly clean the shower tray and tiles ensuring that the surface is free of dirt and grease before applying silicone sealant
Thoroughly dry the shower tray and tiles with paper towel ensuring that all mositure has been removed before applying silicone sealant
A Fugi silicone sealant application with various sized cut-outs at each corner for achieving various thicknesses of silicone sealant bead
The shaped lower edge of this Fugi silicone sealant application tool is designed to remove excess material and leave a neat straight line around the edge of the shower tray
To ease application trim the nozzle of the silicone sealant tube at a slight and angle and do not be tempted to make the exit hole too large
Working from the corner of the shower tray use an application gun to apply the silicone sealant
A Fugi silicone sealant application tool is used to remove excess sealant and leave a neat line around the perimeter of the shower tray
Here we can see the fresh silicone that has been applied to the shower tray and smoothed to a neat finish with the help of a sealant application tool