Landscape edging is used to define the edges of paths and driveways, lawns and planted borders. Metal edging – aluminium or steel – is popular because of its durability and stylish looks, but a harsh coastal environment can be its enemy.
In this blog post, the UK designers and manufacturers of ExcelEdge metal edging explain how to make the best choice.
Which Metal Edging Should I Choose If I Live By The Sea
It’s a well-known fact that saltwater will cause steel to corrode more quickly than freshwater. Where edging is placed in relation to the water will make a difference to how quickly corrosion will take place. As a rule of thumb, any exposed steel within about 3,000 feet (900 metres) of the shore is likely to experience faster corrosion. If coastal flooding at high tides or during inclement weather is a risk, this should also be taken into account.
- If metal is constantly submerged, lower oxygen levels will limit corrosion.
- The intermittent wet and dry conditions of splash and tide zones will contribute to faster oxidation.
- The atmospheric zone above the high water tidemark is the best environment for steel edging.
So if you live close to the sea or any saltwater area, what metal edging will be best for your landscaping? Let’s take a look at the various metals used in landscape edging.
- Mild steel
Uncoated, untreated steel is highly vulnerable to oxidation – more than 100 times more prone to it than aluminium, for example – and is therefore unsuitable for use in coastal areas.
Applying a protective coat to mild steel will delay oxidation. A powder-coated finish is the better option as paints require regular and frequent maintenance and repainting.
- Weathering steel (Corten steel)
While Corten steel relies on the elements to form its protective oxide layer, this process can in some instances be impeded by a coastal environment, to the extent that it equals that of unprotected mild steel.
- Galvanised steel
The galvanisation process applies a zinc coating to steel which helps resist corrosion. Rust will however appear over time where the surface is scratched or worn. In the harshest environments, red rust stains may be visible in less than three years.
However, steel is harder than aluminium and therefore more resistant to scratches and to warping, deforming or bending when exposed to weight, impact or heat.
We offer a range of steel edging that suits a wide range of applications.
Garden edging for delineating soft landscaping such as lawns, borders and gravel paths.
Available in galvanised, untreated or brown powder-coated.
Strong steel edging for soft and hard, high traffic landscapes.
Available in Corten, galvanised or untreated.
3 mm Urban is graded DC01 to BS EN 10130:2006.
6 mm Urban is graded BS EN 10111:2008.
Strong, robust roll-topped steel edging for hard landscapes
Available in Corten, galvanised, untreated or powder-coated to custom RAL colours.
Galvanised Fort is graded EN10346:2015 DX51 + Z275 Coating.
Mild steel fort is graded DC01 to BS EN 10130:2006
Galvanised steel edging for civil construction.
Available in galvanised.
Bison is graded EN10346:2015 DX51 + Z275 Coating
The biggest benefit of using aluminium edging in coastal areas is its higher corrosion resistance. It requires no surface treatment or maintenance to protect it from the elements, although like Corten steel it has a protective outer layer of oxide and this can be broken down by salt.
One possible downside of aluminium is that it is only available in the metal’s bright silver finish, which may not coordinate so well with some landscape designs.
It is also important to check you are using the correct grade of aluminium as some – 2XXX and 7XXX – are unsuitable for coastal environments.
Our aluminium edging is all fabricated from 6XXX grade, which in addition to its suitability for coastal regions, has a better mill finish and good bending properties.
We offer two aluminium edging products that are suited to coastal areas.
Designed for domestic garden use.
AllEdge is made from 6063A grade aluminium.
While designed for commercial use, AluExcel can also be used for domestic projects and is available in ten edging heights ranging from 15 mm to 150 mm.
AluExcel is made from 6005A-T6 grade aluminium.
Which metal edging will you choose?
Ultimately, the choice is yours. Environmental conditions, cost, durability and appearance will all influence your decision, and we hope this guide to the options will help you make the right one.