Can Two Rolls of Insulating Mats Be Joined in Front of a Switchboard?

When the working area in front of a switchboard is particularly wide, or when the existing rolls of insulating mats cannot cover the entire area in a single piece, purchasers often consider joining two rolls of Electrical Insulating Mats to lay them out. This not only meets the on-site dimensional requirements but may also offer greater flexibility than purchasing a single roll of matting in a special size.

However, the suitability of joining two rolls of insulating mats cannot be determined solely on the basis of the area to be covered. Purchasers must also consider the type of seam, edge stability, pedestrian access, product instructions for use, and the insulation protection requirements specified for the project.

Generally speaking, two rolls of insulating mats can be used to cover the area in front of a single switchboard, but the specific laying method must be confirmed. The conditions created by joints formed when two rolls of mats are joined side-by-side, with overlapping edges, or connected lengthwise are not the same. The fact that both rolls of mats meet the relevant product requirements does not mean that any method of joining them is automatically suitable for on-site use.

IEC 61111:2026 sets out requirements for the instructions for use provided by manufacturers of insulating mats, including relevant recommendations for overlapping mats. Therefore, when planning joints, purchasers should consult the specific product’s instructions for use and determine a solution based on the on-site layout and applicable safety procedures.

For electricity companies, EPC contractors, substation project procurement officers and distributors of electrical safety equipment, a more sensible approach is to first measure the area to be covered, then compare the feasibility of joining two rolls with that of continuous coverage, and finally determine the procurement dimensions and acceptance criteria.

When Do Switchboard Areas Need More Than One Insulating Mat Roll?

In switchboard rooms, distribution rooms and substations, the layout of insulating mats should be determined based on the actual work area, rather than simply purchasing mats of the same length as the switchgear.

Common scenarios requiring the laying of multiple rolls include the following.

Firstly, where the front of the switchgear is relatively wide. Where the width of a single roll of insulating mat is insufficient to cover the entire operational area, the option of laying two or more rolls side by side should be assessed.

Second, the operational area is lengthy. If an entire row of switchboards needs to be covered, the length of a single roll may be insufficient; the purchaser must therefore assess the option of joining multiple rolls of mat material lengthwise.

Third, there are distinct operational areas on site. For example, one section may be used for routine operations, whilst another requires coverage of adjacent control cabinets or power distribution equipment. In such cases, the dimensions of the mats, the positioning of the seams and the direction of installation must all be planned in advance.

Fourth, the project requires control over material wastage. When standard rolls cannot be reasonably adapted to the on-site dimensions, the costs and ease of installation of a combination of multiple rolls can be compared with those of bespoke width and length solutions.

It should be noted that the actual coverage requirements for the front of a switchgear cabinet do not necessarily correspond to the cabinet’s external dimensions. Purchasers should also take into account the positions where personnel stand, the operational space, the range of door opening, on-site access routes and the project-specified work areas when taking measurements.

Before determining the quantity of rolls required, it is advisable to first complete a site layout plan and then calculate the required dimensions and quantity of materials.

Three Ways to Arrange Two Insulating Mat Rolls

When two rolls of insulating mats are used in front of the same switchgear cabinet, common layout methods include side-by-side butt joints, edge-to-edge overlaps and longitudinal connections. As the seam positions differ across these three methods, the same assessment criteria cannot be applied across the board.

Side-by-Side Butt Joint: Butt Joint

A side-by-side butt joint refers to laying the side edges of two rolls of insulating mats adjacent to one another, without intentionally having one roll overlap the other.

For example, if a coverage width of approximately 2.4 m is required in front of a switchgear cabinet, the purchaser may evaluate a solution involving two rolls of insulating mats with a nominal width of 1.2 m each, laid side by side.

The combined nominal width of the two rolls is 2.4 m; however, this is merely a theoretical coverage dimension. In practice, it is also necessary to verify the finished width, dimensional tolerances, the position of the edges after laying, and whether there are any gaps at the joints.

Key inspection points for side-by-side installation include:

• Whether the edges of the two rolls of matting are level.
• Whether there are any noticeable gaps at the joints.
• Whether the matting is prone to lateral movement.
• Whether the joints are located in areas with frequent foot traffic.
• Are there any instances of edges curling up or posing a tripping hazard?
• Are the thickness, surface texture and product specifications of the two rolls of underlay consistent?

Side-by-side joining can minimise height differences caused by localised overlaps; however, this does not mean that any joining method can be used indiscriminately. If the seam opens, the edges curl up or the underlay shifts, this may still pose a risk on site.

Edge overlap: Overlap

Edge overlap refers to a situation where part of the edge of one roll of insulating mat covers another roll of mat.

This method may reduce visible gaps in certain areas, but it may also result in variations in thickness, curled edges or obstacles to pedestrian traffic. Therefore, it cannot simply be assumed that overlap is necessarily safer than butt-joining.

Purchasers need to verify:

• Whether the manufacturer has provided clear recommendations regarding the use of overlaps.
• Whether the relevant product specifications stipulate the applicable conditions.
• Whether a noticeable difference in height is created after overlapping.
• Whether the mats can remain stable and are not prone to slipping or curling at the edges.
• Whether the seams impede pedestrian access or equipment operation.
• Whether on-site work procedures permit this arrangement.

A uniform overlap width applicable to all insulating mats should not be arbitrarily specified, nor should compliance with electrical protection requirements be judged solely on the basis of the overlap area.

If the manufacturer has not provided clear recommendations for overlapping, the purchaser should confirm this with the supplier or relevant technical personnel prior to installation, rather than selecting a single dimension as a universal standard.

Longitudinal connection: End-to-End Joint

If a row of switchgear requires a long, continuous coverage area, two rolls of mats may be joined lengthwise.

For example, where a single roll of mat is insufficient to cover the entire row of switchgear, a solution involving two rolls covering different sections may be considered.

This layout requires particular attention to the relationship between the seam and areas where personnel stand.

The purchaser should check:

• Whether the seam is located in an area where personnel frequently stand or move.
• Whether the two rolls of matting are prone to longitudinal displacement.
• Whether there are gaps or raised edges at the seam.
• Whether the two rolls of matting have consistent electrical ratings and meet the applicable requirements.
• Whether the actual coverage area meets the project’s layout and safety requirements.

If the project requires continuous coverage in specific areas, the purchaser should specify this requirement in the technical specifications and assess whether longer rolls should be used instead of assuming that longitudinal splicing will suffice.

What Does IEC 61111:2026 Say About Overlapping Insulating Mats?

IEC 61111:2026 is one of the relevant standards to consider when procuring Electrical Insulating Matting. This edition was published on 4 September 2026 and applies to electrical insulating mats within its specified scope.

Clause 4.8 of the standard, concerning requirements for instructions for use, explicitly addresses recommendations regarding the overlapping of insulating mats. This means that manufacturers should provide the necessary safety information in the product instructions and offer relevant advice regarding known key risks.

However, this requirement should not be misinterpreted as stipulating that all insulating mats must be overlapped, nor does it imply that any method of overlapping will satisfy safety requirements.

Purchasers need to distinguish between three issues:

Even if two rolls of matting individually comply with the relevant standards, one cannot infer from the conformity certificate of a single roll that any method of joining them has been validated.

If the project explicitly requires an overlapping arrangement, the manufacturer’s instructions for use should be checked, and the relevant requirements incorporated into the installation and acceptance procedures.

If the project employs a side-by-side butt joint, it should be confirmed that this layout complies with product requirements and on-site safety procedures, and the joints should be inspected for gaps, movement or tripping hazards.

For specific projects, the applicable version of the standard, contractual requirements and on-site safety procedures should be confirmed by the relevant technical manager.

How to Measure the Area Before Ordering Multiple Mat Rolls

Before deciding to use two rolls of insulating mats, the purchaser should first measure the area to be covered and calculate the required combination of rolls based on the actual dimensions.

It is recommended to proceed as follows.

Step 1: Measure the total front width of the switchgear

Measure the front width of the entire row of cabinets to be covered, rather than just a single cabinet.

If there are gaps between adjacent units, or if additional operational areas need to be covered on site, these factors should be incorporated into the layout plan.

Step 2: Determine the coverage depth of the work area

Measure the actual coverage required extending outwards from the front of the equipment, taking into account personnel standing positions, operational space and on-site access routes.

The coverage depth should be determined in accordance with the project design or relevant safety requirements, and must not be based solely on the standard dimensions of the rolls.

Step 3: Determine the direction of the seams

If two rolls of underlay are laid side by side, the seams will typically run lengthways; if two rolls are joined lengthways, the seams may cross the area where personnel stand.

The direction of the seams affects the actual layout, edge stability and personnel access, and should therefore be clarified prior to procurement.

Step 4: Compare Standard and Custom Sizes

JINPOWER’s current Switchboard Mat product page lists a variety of insulating mat thicknesses, widths, lengths and surface textures, and supports custom sizes according to project requirements.

Specifications listed on the current page include:

The above are the product options published on the website; specific models, size combinations and availability should be confirmed at the quotation stage.

For example, if a frontage width of approximately 2.4 m needs to be covered, one could first compare the option of laying two 1.2 m wide rolls of underlay side by side with that of using a product of a customised width.

However, one cannot simply assume that adding the nominal widths together will guarantee a gap-free coverage area once the material is laid. Actual dimensions, manufacturing tolerances, laying methods and on-site measurement results still need to be verified.

Step 5: Confirm whether seams affect practical use

Once the combination of rolls has been determined, check whether the seams are located in primary standing areas, operational passageways or within the door opening range.

If the seams are likely to cause a noticeable difference in height, mat displacement or a risk of tripping, the layout should be readjusted, or the option of using a single continuous roll should be assessed.

When Is One Continuous Insulating Mat Better Than Two Joined Rolls?

Joining two rolls is not necessarily the most cost-effective or convenient solution. In certain projects, using a single roll of continuous insulation mat may be more appropriate.

Areas Requiring Continuous Coverage

If the project has strict requirements regarding the location of seams, or if seams are undesirable in primary work areas, the continuous coverage option should be prioritised.

Whether continuous coverage is required should be determined based on project specifications, product instructions and on-site safety procedures.

Areas with heavy foot traffic

In areas where people frequently walk, trolleys are used or tools need to be moved frequently, particular attention should be paid to the tripping hazard posed by seams.

If joining two rolls is likely to cause the edges to curl up or shift, using a single roll of insulation mat in a more suitable size may be easier to manage.

Projects requiring minimal on-site cutting

If customised dimensions better match the on-site layout, this can reduce the amount of on-site cutting and splicing required.

However, purchasers must still verify whether customised dimensions are available, whether they affect delivery times, and whether they meet the required electrical ratings and other technical specifications.

Areas requiring simplified follow-up inspections

The more seams there are, the more edges and joints typically require attention during on-site inspections.

Adopting a continuous coverage solution can reduce the management of joints, but it does not replace the inspection, cleaning and maintenance requirements of the insulating mats themselves.

Therefore, purchasers should comprehensively compare material costs, dimensional fit, installation workload, joint management and subsequent maintenance, rather than merely comparing the price of individual rolls.

Common Mistakes When Joining Insulating Mat Rolls

Focusing only on coverage area without checking joints

Simply adding the nominal areas of two rolls of mat does not guarantee that the joined section will form a working area that meets requirements.

The positions of the seams, the condition of the edges and the actual dimensions all need to be verified.

A standard overlap is generally safer than a butt joint

Overlapping may reduce visible gaps, but it may also create height differences, slippage or tripping hazards. The specific method should be confirmed in accordance with the manufacturer’s recommendations and on-site requirements.

Securing seams with standard adhesive tape

Standard adhesive tape, glue or other fixing materials must not be assumed to be suitable for Electrical Insulating Mats.

If it is necessary to secure or join the mats, it must first be confirmed whether the manufacturer permits this method, and whether the materials used will affect the performance, surface condition or subsequent inspection of the insulating mats.

Joining two rolls of mat using metal fasteners

Do not use metal nails, metal clamps or other unauthorised fastening methods to treat joints. Any mechanical fastening method must undergo an assessment of suitability and comply with product specifications and on-site safety requirements.

Ignoring specification differences between two rolls of product

The electrical rating, dimensions, surface structure and applicable requirements of each roll of mat must be verified separately.

Do not assume that two rolls of product can be combined arbitrarily in the same area simply because they are the same colour or have similar thicknesses.

Failure to consider subsequent inspection and replacement

If a roll of matting needs to be replaced, the purchaser should also consider whether the replacement product is compatible with the original layout, and whether the joints will need to be reassessed following re-installation.

For critical electrical areas, it is recommended that records of product model numbers, dimensions and installation layouts be retained to facilitate subsequent maintenance and replacement.

What Buyers Should Confirm Before Ordering Two Rolls of Matting

Prior to bulk procurement, it is recommended that the following information be included in the RFQ or project technical confirmation document.

Purchasers should clarify these requirements at the quotation stage, rather than waiting until the products have arrived on site to discuss how they will be joined.

If the project requires a specific layout, it is recommended to provide on-site dimension drawings or a simple floor plan in the RFQ, so that the supplier can verify the mat configuration based on actual requirements.

How JINPOWER Supports Switchboard Matting Layout and Custom Sizes

JINPOWER supplies Electrical Insulating Rubber Mats for switchboards, distribution boards, substations and industrial electrical areas.

Existing products include Electrical Insulating Rubber Mats for Switchboards, available in various electrical ratings, thicknesses and surface textures, as well as customised dimensions to meet project requirements.

For projects requiring two or more rolls of insulating mats, it is recommended that the following information be provided when requesting a quotation:

• The total width to be covered on the front of the switchgear.
• The required coverage depth.
• The electrical rating required for the project.
• The desired thickness and surface texture.
• Whether seams are permitted, and the planned layout.
• Whether custom widths or lengths are required.
• Relevant product documentation and acceptance criteria.
• Purchase quantities and delivery times.

Based on this information, standard size combinations and bespoke dimension options can first be compared before determining the most suitable supply configuration for the project.

For purchasers, the focus should not be on whether to procure one or two rolls, but rather on ensuring consistency between the final supply dimensions, on-site layout and acceptance criteria.

JINPOWER’s product specifications and customisation capabilities are subject to specific model numbers, technical documentation and order confirmations. For projects involving special seam treatment, the manufacturer’s recommendations for use must be confirmed prior to installation; unconfirmed joining methods should not be regarded as universal installation solutions.

FAQ: Joining Electrical Insulating Mat Rolls

Can Two Insulating Mat Rolls Be Used in Front of One Switchboard?

This may be considered, but must be confirmed based on the actual layout, product instructions and project requirements. The fact that two rolls of mat each meet their respective product requirements does not automatically prove that any joining method is suitable for the site.

Should Two Insulating Mat Rolls Be Overlapped or Placed Side by Side?

There is no single answer applicable to all products and scenarios. Joining side by side may result in gaps, whilst overlapping may create height differences or edge misalignment. The decision should be made in accordance with the manufacturer’s recommendations, on-site conditions and applicable safety procedures.

Does IEC 61111:2026 Require All Insulating Mats to Overlap?

This is not the correct interpretation. The standard requires manufacturers’ instructions for use to include relevant recommendations regarding the overlapping of insulating mats; however, this does not equate to a requirement that all insulating mats must be laid with an overlap, nor does it prescribe a uniform overlap width for all applications.

Can Ordinary Adhesive Tape Be Used to Join Two Insulating Mats?

This cannot be assumed. Before using any adhesive tape, glue or other fixing materials, it should be confirmed whether the manufacturer permits this, and whether the method will affect product performance, surface condition and on-site usage requirements.

Is One Continuous Mat Always Better Than Two Rolls?

Not necessarily. Continuous coverage can minimise the need to manage seams, but purchasers must also weigh up factors such as dimensional compatibility, cost, customised lead times and on-site installation conditions. The final solution should meet the project’s requirements.

What Should Buyers Send When Requesting a Switchboard Matting Quote?

It is recommended to provide the total on-site width, coverage depth, required electrical rating, thickness, surface texture, number of rolls, joining requirements and delivery terms. If the project has specific installation requirements, a layout plan or details of seam locations should also be provided.

Final Recommendation: Plan the Seam Before Ordering the Mats

Two rolls of Electrical Insulating Matting can be used to cover the area in front of the same switchboard; however, whether side-by-side, overlapping or lengthwise joining is appropriate must be determined by considering the product specifications, on-site layout and applicable safety requirements.

Purchasers should first measure the area to be covered, then compare standard roll combinations with bespoke sizing options, and clearly specify the jointing method, edge stability and acceptance criteria in the procurement documentation.

For JINPOWER’s Switchboard Matting, the existing product range offers a variety of thicknesses, widths, lengths and surface textures, and supports bespoke sizing according to project requirements. Purchasers can confirm the most suitable supply solution at the quotation stage by providing on-site dimensions and the intended layout.

What truly matters is not simply joining two rolls of matting together, but ensuring that the joint layout, product specifications and on-site usage requirements are mutually compatible.