© 2007 Dural (UK) Ltd
Perimeter Movement Joints
BS 5385 states that allowance for perimeter movement should be made on floors larger
than 2mtrs x 2mtrs. As this is about the size of a smallish Bathroom or Kitchen this
one rule can cause some fixers to dismiss all the movement joint rules as impractical
and unrealistic -
Whilst this view can be understood, if taken from a practical point of view it should be remembered that many small domestic floors tiles are fixed abutted to wooden skirting boards that can absorb the small degree of movement that occurs in these small floor areas. Alternatively the skirting boards may have been removed allowing an air space for movement. (To be hidden after replacement of the Skirting). For domestic situations this is acceptable. For commercial situations where the floor areas are considerably larger this is inadequate.
Larger floors have a greater requirement for movement accommodation. Frequently constructed in sections designed to move independently from each other, these sections must also have designed movement accommodation where they join vertical surfaces or fixed obstructions.
Modern construction techniques with floating insulated floors, heated floors have definitely greater requirements for movement accommodation. Preformed and coordinated perimeter and intermediate movement joints can prevent many premature failures.