Fence Rails

Rails

Cost per metre: £
Longevity: 30-40 Year
Lengths: 2.4- 4.8 metres
Strength: Length between post should not exceed 3 metres and advisably is best to be no more than 2.4 metres long. Often sagging of the fence occurs between the posts due to overloading of 2+ metres long rail post centres.
Description: Has a machine sawn bevelled slope on top of the rail to allow water to diperse easily and not saturate the of the rail.
Dimensions: Cut from 125mm wide x 50mm thick timber equally into 2 rails.
Pros: Cant rails have the greatest longevity as they do not totally saturate and have a greater choice of lengths. This rail has a slopped top edge and is a good fence option.
Cons: Not enough strength for heavier load bearing fence paling boards such as Half log. For a greater strength an extra square cut rail can be added under the Cant Rail or a more commonly option is to use a support at a center point between the posts at the gravel board to paling board which will absorb some of the fence weight and reduce the risk of the fence sagging.

Cost Per Metre: £
Longevity: 20-30 years
Length: Normally in 3 metre lengths
Strength: Has good supporting strength due to the way rails are machine sawn.
Description: Allows excellent water dispersal, combined with good supporting strength.
Pros: Has an angled surface which allows good water dispersal which a fence rail needs. Arris rails are stronger than Cant rails due the deeper supporting edge of the Arris Rail where Paling boards are nailed to.
Cons: Due to the triangular shape of Arris rail presipitation saturates all over the rail and weathers quicker than Cant Rail. Arris rail only in 3 metres length so there is less choice when deciding how to build a fence.

Cost per metre: £
Longevity: 15-25 years
Length: 1.8-4.8m
Strength: Stronger than Arris Rail or Cant Rail.
Description: Square cut rails have good strength but water will saturate the top of the horizontal surface with no disperal run off. This speeds up the rotting process and is a very good reason to paint a water protection coating on these rails.
Pros: Best strength and available in varying dimensions
Cons: Good durability but not as good as a machine bevelled rail.

Cost Per Metre: £
Longevity: 20-30 years
Length: 1.8-3.6 metre lengths
Strength: Good strength
Description: A Half log round rail is cut from a machine rounded length of timber sawn into 2 equal halves. These rails can also be used as paling boards
Pros: Is a half circular rail that allow a good water runoff
Cons: Are the most expensive of the timber fence rails and not often used. A machine rounded rail has a smooth surface much the same as a planed rail and will not absorb the preservatives as well as sawn cut timber.

Cost per bracket; £
Longevity: 40-50 Years
Composit: Hot dipped Galvanised Steel which gives it a 20 micron coating which makes it a true exterior grade.
Strength: Very Good
Description: Used inconjunction when fixing wooden fence rails to a fence post for an Offset Fencing style.
Pros: strong supports
Cons: allows timber saturation

Costs per bracket: £
Longevity: 25-35 years
Composit: Galvanised
Strength: Very Good Strength
Description: The galvanised bracket is cut from a 4 micron galvanised coated steel sheet. Used for fixings wooden rails to fence posts using and Inline style.
Pros: good for fixing arris rails and saves chamfering or searching for chamfered rails.
Cons: A little unsightly.

Continental panel rails should be a minimum of 50mm depth x 32mm thick x 1800mm long
Traditional UK made panels should a minimum of 50mm depth x 32mm thick x 1830mm long
Arris rail maximum length for a fence rail should be no more than 3 metres. Three metre post centres still overloads Arris rails once the wood starts to weather. Arris rail come in only 3 metres lengths but our recommendation is for 2.4 metres as a maximum.
Cant rail should be no more than 2.4 metres
Square cut rails can be up to 3 metres long with a minimum depth of 70 mm x 45mm thick.
The advised maximum rail length is 2.4 metre post centres. Some fences require lesser spacing between posts due to varying factor like weight, height and how wind prone locations.
The closer the posts are, means the stronger the fence will be and more likely to stay up in high winds, less stress on the panels and fixings long term.

Feather edge fencing should have at least 1 rail per 600mm of height of the fence and a minimum of 2 rails. This is due to the thin part of the fence board needing support across each length, which reduce the boards cupping away from alignment.
More ridged fence Palins like half log or 100mm x 22mm square cut boards which are used for hit and miss, do not need the extra fixing point as the boards are more ridged. The rails however would need to be stronger as these Palin boards are much heavier.