Fencing: Tips & Traits
Easily worked and readily available in a variety of types, shapes, sizes, timber can last longer and perform better than many alternative materials, either in its natural form or with wood preservative treatment.
Fencing is a significant contribution to the UK’s annual softwood consumption. British softwoods are lower strength species such as pine and spruce. These often grow faster than many imported species from northern Europe. Hardwood species are popular too, namely oak and sweet chestnut.
Timber fencing is diverse in its use and style, and performance requirements can very considerably. Examples include:
Domestic – garden fencing, boundary fencing
Boundary & Perimeter – barriers against intruders, protecting hazardous areas (sub stations, pylons, wells, and open drains)
Noise Barriers – motorway/road fencing, railway fencing
Health & Safety – hilltop/cliff edge, playground, workplace
Timber is a natural product that does not benefit from exact dimensional or compositional consistency. It expands and contracts due to changing climatic conditions and is prone to splits (shakes), cracks (checks), knots, twisting, bowing, and bending. When machine sawn, it can also exhibit saw marks, rough edges (with some splintering) and minor dimensional discrepancies. However, Timber has several general characteristics that condition to its suitability as a material for fencing.
- Versatility: It is an easily workable material, available in a range of sizes and lengths, readily formed into a range of product shapes and sizes.
- Strength: Appropriate species selection, with additional protection where necessary, can withstand structural damage caused by, for example, animals or wind load.
- Sustainability: A renewable material, timber is available in a wide variety or sustainability sourced certified species.
- Durability: Together with the appropriate timber species selection, and relevant preservative treatment for the use and desired service life, timber can outlast and out-perform many other alternatives.
There a several considerations to make when constructing a new or replacing an existing fence, including mother nature and the resistance to its elements, ease of maintenance, and service life. Specification may require a fence incorporating timber to comply with the relevant parts(s) of BS 1722. Road noise barriers are subject to even more stringent requirements enforced by the Department of Transport.
It is important to consider the use of the fence along with the desired appearance and local aesthetics to determine what type of fencing to choose. Core fencing types include:
- Post and rail fences
- Palisade, picket and pale fences
- Close boarded fences
- Panel fences
- Lattice and trellis
- Acoustic fences
Size, Strength & Colour
The measurements of the fence is critical, particularly knowing the overall height, length and spacing of the fence, so that the supplier can provide the correct individual components of the structure.
BS 1722 guidance refers to four distinct timber quality selection methods depending on the type of fence. For commercial use, it is advisable for a structural engineer to assess the structure and the possible loads that it may experience. Apart from knots, other limiting characteristics include wane, slope of grain, checks, and splits, resin and bark pockets, pin worm and distortion.
Defects such as rot, active insect attack and Lyctus damage are specifically excluded from BS 1722 as it fives some generous allowances for features and they are often technically compliant. However, it is important that timber suppliers refer to the correct part of the standard that details the requirements for timber in each fence type. Where a certain colour, style or character is required, thought should be given to the appearance of the timber. This will have some impact on the timber species that is selected.
To access the wealth of experience and information of Fencing specialists, contact Worcester Timber Products.