FencingWise

Single vs Double-Skin 358 Fencing: A Factory Order Comparison

A second layer of 358 mesh changes the fabricated and supplied assembly, not only its panel count. For a custom double-skin quotation, specify layer orientation, extent, separation and connections with the approved support arrangement. We recommend comparing complete systems so added material is not mistaken for an automatically higher security rating.

By FencingWise Editorial Team · Updated 3 November 2026.

Single layer close mesh fence along an industrial boundary
A single close mesh fence provides the baseline for the assembly comparison.

Establish what “double skin” means on the drawing

Ask for a section through the assembly and an elevation showing both layers. Two parallel layers with their wires aligned have a different projected opening from two layers turned through 90 degrees. An offset arrangement introduces another pattern again.

For double-skin fencing, confirm the mesh pattern, relative orientation and attachment of both layers on the system drawing. A second layer does not by itself establish an equivalent or higher security rating.

Two layer close mesh security fence viewed along the boundary
Published double-skin fence example. The image does not establish the layer orientation or a tested rating for another system.

Nominal mesh dimensions also need a stated measurement convention. A centre-to-centre pitch is not the same as a clear opening between finished wires. Coating thickness and the relative position of the two layers affect the latter.

A useful detail therefore identifies:

  • The wire directions and dimension convention for each layer.
  • Whether layers touch, overlap locally or are separated by spacers.
  • The face from which fixing heads and nuts can be accessed.
  • How both layers terminate at corners, gates and changes in level.
  • Whether the second layer extends over the full fence height.

Compare the assemblies on the same basis

Item Single mesh layer Two mesh layers
Panel schedule One panel position per bay and height section Separate position for each layer
Fastening Secures one mesh assembly to its support Must secure both layers using the designed load path
Inspection access One mesh face and its joints Additional interfaces may be concealed
View through the fence Depends on mesh and viewing angle Also depends on alignment and separation
Replacement Remove the affected panel assembly Establish which layer can be removed first
Supporting structure Checked for the selected panel and site Recheck added weight and wind behaviour

Doubling the number of layers does not establish twice the intrusion delay. Delay depends on a complete configuration and a defined test. Similarly, doubling panel mass does not mean that wind force simply doubles: shielding and aerodynamic interaction need a suitable design basis.

Work out the additional panel material

Consider an illustrative straight run with 20 bays, each using a 2.50 m wide × 2.40 m high mesh panel. Assume the two-skin option has two full-height layers of the same panel, without extra overlaps in this simplified quantity calculation.

One panel has a gross face area of:

2.50 × 2.40 = 6.00 m².

The single-skin order contains 20 panels, or 120 m² of panel face area. The double-skin order contains 40 panels, or 240 m². The fence still encloses the same nominal 50 m run; it has not become 100 m of boundary.

If the estimating mass is assumed to be 8 kg/m², panel material alone would be 960 kg for one layer and 1,920 kg for two. The extra 960 kg excludes posts, brackets, packaging and any difference in the actual manufactured panels. These are estimating assumptions, not supplied weights.

For an option with the second layer only on the bottom 1.20 m, calculate its area separately: 20 × 2.50 × 1.20 = 60 m². The total becomes 180 m², subject to the actual panel divisions and overlaps. A half-height second layer should never be priced or described as a full-height assembly.

Check the places where layers stop

Draw how both skins end at gates, corners and level changes, then assign special panels and spacers their own references. The factory schedule should distinguish full-height and partial-height second layers and show which connection captures each panel. Retain inspection views before concealed interfaces are closed so the final records can demonstrate the accepted layer arrangement.

At a corner, each layer can require a different edge overlap. A plan view should show whether a gap appears between the last wire and the post. On stepped ground, check both the exposed bottom opening and the vertical transition between adjacent panels. The bottom-gap survey method explains how to record those positions.

Inspection photographs should include the layer relationship before the closing clamp or second panel conceals it. A photograph of the finished outer face alone cannot establish that the internal arrangement matches the approved section.

Select the simpler arrangement that meets the requirement

Compare the approved single- and double-skin options by panels, altered fixings, support requirements and replacement access. Ask for the additional fabrication and packing scope to be identified separately. Where certification is required, resolve the exact configuration before ordering; combining two otherwise familiar panels does not create verified performance for the combined system.

For procurement, compare a complete single-skin system with a complete double-skin system. Price the additional panels, altered connections, structural revisions, transport weight and installation sequence separately. This makes the cost of the second layer visible without presenting additional steel as proof of additional certified performance.