Recycled Plastic Edging Information

How is Filcris Recycled Path and Lawn Edging used?

Installing the lawn or path edging material is very simple – simply treat it in the same way as timber edging. We have avoided the route of making a complex system which clicks together because by keeping the product simple, we allow the user to make their own decisions. This makes for a little bit more work but a much more satisfactory result.

There are 2 main ways of using the edging boards:

Flush – this is level with the ground surface and / or path. This is the standard way of using the edging boards as a path edging, allowing grass to be cut without the boards impeding the blades, and reducing trip hazards. Since the material is held in position by the soil and the path surface it is butting up against, fewer stakes may be needed.

Raised – this is useful where beds and borders are being edged, to prevent soil and mulches from spilling onto the lawn, patio or decking. The edge can be sunk partially into the ground to adjust the depth and to get a more secure fixing. It should be held in position with stakes – we supply a wide range of sizes for different applications. You will find that more stakes will be required for this type of edging.

The installation method for both is as follows:

  • Equipment:
    • Tape measure, spirit level, string or line and pins or canes for setting out.
    • Lump or sledge hammer to knock in stakes.
    • Crosscut saw for trimming planks and stakes.
    • Clamps for holding planks to stakes.
    • Cordless drill/driver for fixing planks to stakes with suitable drill/driver bits and countersink.
  • Materials: edging planks and edging stakes. See below for guidance on selecting the appropriate types of planks and stakes for your project. 5mm x 40mm wood screws for fixing 18mm planks and 5mm x 50mm for fixing 24mm and 25mm planks. 2 screws per stake / plank fixing will be needed.
  • Preparation: Decide where the edging is to run, and mark out with sand guide-lines or a hose, if required. It is a good idea to dig a trench slightly deeper than the depth of the plank i.e. 160 – 170mm and wider than the planned width makes handling much easier. We find a spade's width trench (around 250mm) works well. Keep the excavated material close by if it will be needed for backfill once the edging is finished.
  • Setting out: Set up a taut string line with canes / steel pins following the desired course and level.
  • Joints: We do not recommend butt joints sharing a single stake except when combined with a 300mm bracing piece (from an offcut) to span two adjacent rails OR when the joint is on a right angle corner. Alternatively 60 degree angles can be cut top and bottom of the two planks to make a Mitre Joint or two stakes to make a Double Stake Joint (see pictures to right). Double Stake Joints are recommended on tight curves and changes of direction at other than 900.
  • Fixing: Clamp the plank to the first stake, knock it in with a sledge or lump hammer making sure it is perpendicular and has a good solid fixing. Clamp the plank onto the other stakes spaced as required checking to ensure the level is correct. Before hammering in the stakes make sure that they are spaced closely enough to support the plank and retain the soil if the edge is raised.  Trim any excess plank material and arrange the joint for the next plank. Fix the planks to the stakes using 5mm x 40mm – 50mm wood screws, pre-drilling through the plank into the stake and countersinking the plank. 2 screws per stake / plank fixing will be needed.
  • Finishing off: The stakes can be trimmed flush with the top of the plank or 10 – 30mm below the top of the plank for a neater, hidden finish, using a handsaw. The soil and other materials can be backfilled and reseeded if required.

The method for raised edging is the same but the trench can be shallower or not required and the stakes need to be spaced closer together.

Frequently Asked Questions:

What type of planks should be used?

This will depend on the type of project being undertaken:

Raised Edging: Rigid Edging Plank,

Raised Edging with Extra Stakes: Flexible Edging Plank

Flush Edging, very straight edges: Rigid Edging Plank

Flush Edging, gentle curves: Rigid Edging Plank, Flexible Edging Plank

Flush Edging, tight curves: Flexible Edging Plank

What type of stakes should be used?

Flush & raised edging into solid ground: 40mm x 40mm x 300mm, 40mm x 40mm x 450mm, 50mm x 50mm x 300mm

Flush & raised Edging in to looser soil: 40mm x 40mm x 450mm, 40mm x 40mm x 600mm, 50mm x 50mm x 600mm

Tight curves or free ends: 40mm x 40mm x 450mm, 40mm x 40mm x 600mm, 50mm x 50mm x 600mm

Of course other types of stakes can be used, although if timber stakes are used there is a risk that they will rot and if the edge is of the raised type it may fail. With flush type edging this is less of an issue since the edging planks are supported by the soil and path material.

How many stakes are needed?

This is a difficult question to answer since it depends on what type of edging board is being used, how the edging is being installed, what shape is desired and how high you want it. On average we would recommend the following spacing:

18mm x 140mm: Flush: 750mm Raised: 500mm

25mm x 150mm: Flush: 1000mm Raised: 750mm

Bear in mind the following:

  • If the edging is to be used as a raised edge we would recommend 1 per 500mm for 18mm thick boards and 1 per 750 mm for 25mm thick boards.
  • If the edging is curved you may need fewer stakes. On a gentle curve it will not be very different
  • But on a very tight circle the strength of the curve can hold the circle in position. The image to the right (“Curves held in position with few stakes”) shows a raised bed made from 18mm x 140mm planks with only 5 stakes.

How do I work with the recycled plastic?

Recycled plastic can be cut with a handsaw in exactly the same way as timber. Fixing the planks onto the stakes is best achieved with screws (simple woodscrews will work, we tend to use Spax or Turbo Ultra type screws which can self countersink). If screwing a pilot hole will be needed. The material cannot be glued – it is Polyethylene which does not bond well to any glues.

Does the material warp or bend?

Recycled plastic does not warp when it gets wet like timber does but it does expand and contract with changes in temperature. An expansion gap of about 5 - 10mm between the ends of planks will accommodate this movement.

Can the material just be pushed straight in? 

It can be knocked in with a rubber mallet, although making a slot with an edging spade will make it easier. However we recommend that you make a shallow trench and backfill to the plank.

Why don’t you make it easier for the edging board to be pushed straight in?

To get the best of the strength benefits of recycled plastic it has to be a reasonable thickness. Thinner non recycled plastic products which can be pushed straight in are available but they do not have either the strength or the durability of our recycled products, and when they break you will have to add to the waste mountain rather than take away from it! To be pushed into the ground the plank would have to be wedge shaped. But a wedge shaped plank will not curve properly – it wants to make a cone rather than a circle, and it will bow out at the top. Because flexibility is the greatest strength of this product, we felt that anything which compromises that strength is a flaw.

We also know as experienced gardeners and trained landscapers than when you are making an edge you don’t generally do so in the middle of a lawn! It is normally either to tidy up an existing bed or path, or while you making a new one. In either case it is straight forward to dig out a shallow trench, stake the material in position and then back fill up to it.