Where should I provide gaps for expansion?
This is a common question when specifying timber flooring. Whilst it is most important, it can also be complex, and the correct detailing will depend on the demands of the particular design.
It is critical that enough provision for expansion is made across the width of the floor, or there may be an increased risk of the development of defects or failure of the floor in service. Guidance on the provision of expansion gaps is given in BS 8201 and in our Wood Information Sheet ‘Decorative Timber Flooring'. (link)
Generally, for most residential properties of average size, movement may be accommodated by providing an unfilled expansion gap of a width of between 12mm to 15mm around the perimeter of the room and at all rigid upstands. However, when wider boards are specified or when the flooring is to be installed over a large area, intermediate provision for expansion across the width of the floor may also be required.
Further information can be found in the publications listed below.
TRADA also provides a range of services for building designers, product manufacters and end users of timber flooring, including the design, specification or inspections of timber flooring, for more information please follow this link
Decorative Timber Flooring.
Outlines the types of decorative flooring available ie solid timber and multi-layer or engineered types. It discusses the timber properties required, suitable species and the all-important considerations of environmental conditions and moisture content. Finally, floor construction, laying and finishing seals are considered.
Sealing timber floors: A best practice guide
Deals with seal types and the selection, floor preparation, schedule specification and application of seals. Identifies common faults and their prevention. Covers polishing and maintenance and measures which can be adopted to avoid wear. Refurbishment and stripping of existing floors is also covered.
Seals for timber floors: A specification guide
Provides objective guidance on commercially available seals. Thirty products were subjected to a programme of laboratory tests, each dealing with a different performance criterion. A list of 'top ten' products for each of the tests allows users to select products that best meet the demands created by particular end-use environments. Describes the test methods used and explains how to use the guide through worked examples.
