Your fence ought to give you many years of service; much more if you make sure that it is adequately preserved and you carry out routine maintenance checks.
Timber Preservatives
If at all possible, buy fence timber which has been factory-impregnated with preservative, as this can be considerably more effective in penetrating below the surface of the wood than home applied treatment options. When erecting a fence, all cut ends must be soaked in preservative for a day prior to use.
Unless fences are made of a natural rot-resisting wood, like cedar or oak, you'll also need to treat them regularly with a wood preservative. Re-apply solvent-based products every two or three years and water-based preservatives or creosote every 4 years.
Creosote
Creosote is an effective and popular treatment for preserving fencing. However, it has a very strong smell, which many people may find objectionable. It is also poisonous if inhaled, ingested or absorbed through your skin, which means you must wear protective clothing when applying it. For this reason, creosote isn't recommended for fences which support plants.
Water Based Preservatives
These are much less toxic to plants and also less unpleasant to use. They stop the growth of surface moulds and enhance the look of the timber. However, they're generally less effective at controlling rot.
Wood-Pitch Preservatives
These kinds of preservatives produce a barrier which helps prevent water penetration, making the timber too dry for bacterial activity.
Repairing Support Posts
Among the important problems that develops as a fence ages is broken wood support posts. If the damage is at soil level, the most effective way of repairing is using a concrete spur - this is a small post sunk into the ground alongside the current one and bolted to it to provide support.
1 Dig a hole 45-60 cm (18-24 in) deep around the weakened post and saw off the rotten part.
2 Soak the cut end of the timber post with a wood preservative.
3 Place the concrete spur into the pit, resting it against the post, and pack hardcore around the base to support it.
4 Push bolts through the holes within the spur and tap them with a hammer hard enough to form an impression on the wooden post.
5 Remove the bolts as well as the spur then drill holes through the post for the bolts.
6 Bolt the concrete spur onto the post, tightening the nuts on the spur side so that the wood post is not damaged.
7 Make certain that the post and spur are vertical, if necessary brace them in position temporarily with stakes pushed into the ground.
8 Fill the hole using a fairly stiff concrete mix tamping it down firmly to remove any air pockets.
9 Once the concrete has set (after around one week, remove the supporting stakes and cut off any excess length from the protruding bolts.
Repairing Arris Rails
Broken arris rails are usually easily fixed with specially angled steel brackets. These are available in styles either to support a rail which has rotted where the end fits into the post, or to brace a broken rail in the center. Either styles are simply screwed into place.
Timber Preservatives
If at all possible, buy fence timber which has been factory-impregnated with preservative, as this can be considerably more effective in penetrating below the surface of the wood than home applied treatment options. When erecting a fence, all cut ends must be soaked in preservative for a day prior to use.
Unless fences are made of a natural rot-resisting wood, like cedar or oak, you'll also need to treat them regularly with a wood preservative. Re-apply solvent-based products every two or three years and water-based preservatives or creosote every 4 years.
Creosote
Creosote is an effective and popular treatment for preserving fencing. However, it has a very strong smell, which many people may find objectionable. It is also poisonous if inhaled, ingested or absorbed through your skin, which means you must wear protective clothing when applying it. For this reason, creosote isn't recommended for fences which support plants.
Water Based Preservatives
These are much less toxic to plants and also less unpleasant to use. They stop the growth of surface moulds and enhance the look of the timber. However, they're generally less effective at controlling rot.
Wood-Pitch Preservatives
These kinds of preservatives produce a barrier which helps prevent water penetration, making the timber too dry for bacterial activity.
Repairing Support Posts
Among the important problems that develops as a fence ages is broken wood support posts. If the damage is at soil level, the most effective way of repairing is using a concrete spur - this is a small post sunk into the ground alongside the current one and bolted to it to provide support.
1 Dig a hole 45-60 cm (18-24 in) deep around the weakened post and saw off the rotten part.
2 Soak the cut end of the timber post with a wood preservative.
3 Place the concrete spur into the pit, resting it against the post, and pack hardcore around the base to support it.
4 Push bolts through the holes within the spur and tap them with a hammer hard enough to form an impression on the wooden post.
5 Remove the bolts as well as the spur then drill holes through the post for the bolts.
6 Bolt the concrete spur onto the post, tightening the nuts on the spur side so that the wood post is not damaged.
7 Make certain that the post and spur are vertical, if necessary brace them in position temporarily with stakes pushed into the ground.
8 Fill the hole using a fairly stiff concrete mix tamping it down firmly to remove any air pockets.
9 Once the concrete has set (after around one week, remove the supporting stakes and cut off any excess length from the protruding bolts.
Repairing Arris Rails
Broken arris rails are usually easily fixed with specially angled steel brackets. These are available in styles either to support a rail which has rotted where the end fits into the post, or to brace a broken rail in the center. Either styles are simply screwed into place.
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