If you’ve got a question about any aspect of tiling – The Tile Association’s got the answer. Take a look at the following frequently asked questions.
Why would you use a primer before adhesively fixing tiles?
To promote both adhesion and durability of the bond and where required, reduce the porosity of the substrate.
Can I use PVA as a primer before adhesively fixing tiles?
PVA should never be used.
How long should Gypsum Plaster be left to cure?
Ensure that the plaster has been allowed to cure for a minimum of 4 weeks, is dry and has been applied to a flush and plumb finish.
How long should cement:sand screeds be left before tiling?
Any screed containing Portland cement to BS EN 197-1:2011 must be allowed to cure for at least 7 days by preventing the surface from drying too quickly, e.g. by covering with a polythene sheet and then allowed to dry out for a further 2 weeks.
Can I tile to timber walls?
Timber is no longer considered to be a suitable substrate (BS 5385 Part 1 2018).
What is the minimum grout joint width for wall tiling?
For tiles with a facial area <0.1sqm with no side over 600mm long, joints should not be less than 2mm wide. For tiles with a facial area 0.1sqm to 1sqm with no side over 1200mm long, joints should not be less than 3mm wide.
What is the minimum size grout joint for floor tiling?
The width should not be less than 3mm (BS 5385-3).
Why has my grout gone patchy/ colour variation?
Cleaning off too early can affect the colour consistency, creating a patchy colour appearance and can also affect the grout strength, leaving a weak, dusty surface layer.
How long after tiling should I leave it before using the shower?
When the shower is newly tiled, allow a minimum of 14 days before putting the shower into use, as recommended in BS 5385 Part 4.
Can I tile to 9mm plywood overlay on a timber floor?
15mm is the minimum thickness of plywood recommended in BS 5385-3. Fix wood-based sheets and boards to joists and noggins at 300mm centres using countersunk screws with a length and strength of fixing to ensure adequate penetration into the joists and noggins, taking care not to damage any under floor services.
I’m an architect, can I access technical information?
Technical Documentation from The Tile Association is available to download free of charge to UK architects who have registered with TTA. Sign up here.
The Tile Association shares more free tiling tips and guidance in The Tiling Guide, a handbook with practical information on key installation issues available at www.tiles.org.uk/tiling-guide/, and on TTA’s YouTube Channel at www.youtube.com/@TheTileAssociation_.
Further information is available for purchase in TTA’s Technical Publications, free for all TTA members to download: www.tiles.org.uk/technical-support/technical-publications/
Can’t find what you’re looking for? TTA members benefit from unlimited technical advice – simply contact technical@tile.org.uk.
