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isoweld®

Precision Induction Welding

The isoweld® fastening system uses induction welding to secure single ply membranes to dedicated stress plates, delivering a non-penetrating fastening solution. The innovative system increases installation efficiency, ensures security, and reduces overall project costs.

Download Brochure
SFS isoweld® induction welding fastening system tool

50%

Potential fewer fasteners

Cost savings advantage

3s

Welding time

Fast welding, speedy installation

20%

Potential savings

On the total install cost

40m+

Square meters

Successfully installed worldwide

The benefits of isoweld®

The Isoweld induction welding machine provides multiple benefits for efficient and high-quality welding.

Efficiency

  • Induction welding achieves secure welds in as little as 3 seconds, significantly speeding up installation
  • Membrane-compatible wheels improve roof manoeuvrability and productivity

Security & Reliability

  • Search and Find functionality keeps the tool aligned on the plate and prevents welding if misaligned to avoid incorrect or partial welds
  • Mechanical fixing supports pull-out testing and wind-load calculations

Ergonomics

  • Height-adjustable handles support an ergonomic working position and reduce the need to bend down
  • Improved installer comfort helps to reduce strain and supports productivity

Cost Efficiency

  • Field-fixed positioning enables even fastener spacing without membrane penetration and may require up to 50% fewer fasteners
  • Single membrane width with no cover strips reduces welding and material costs

See isoweld® in action

See the future of induction welding in action with a full introduction video and a real-world isoweld® B case study.

What is isoweld®?

The isoweld® system uses induction technology to weld single ply membrane to dedicated stress plates, securing it to the roof deck. The innovative system increases efficiency, ensures security and saves on cost.

The isoweld® system comprises of:

isoweld® induction tool

A user-friendly and ergonomic stand-up induction welding tool.

It contains integrated safety and security features, such as search & control functions, temperature & power compensation, quick & simple calibration process, ensuring proper and correct welds.

Hand welding tool

This has a flexible 6m cable, for use in narrow, vertical and tight roof spaces. It's used in conjunction with the isoweld® induction tool.

Magnet set

Set of 10 magnetic heatsinks, which are positioned on the waterproofing membrane over the FI-P stress plate to apply pressure and to dissipate heat. Extension rods included for working in an up-right position.

SFS Load distribution Plates

The FI-P-6,8 is suitable for an all-metal fixing application, whilst the FI-P-16,0 is usable with the FI-R-20 sleeves. There are 3 versions of the SFS load distribution plates, in 3 distinct colours, designed to be suitable with PVC, TPO & EPDM membrane types.

SFS FI-R-20 Sleeves

SFS FI-R-20 sleeves are from temperature resistant polyamide, making it suitable in induction welding applications. The FI-R-20 sleeves are designed with a low profile, to help prevent ghosting and has an optimised tip for easier installation.

SFS High Performing Fastener

SFS have a large range of fasteners compatible with the Isoweld® fastening system, available for all substrates.

The isoweld® fasteners and stress plates are covered under our Flat Roofing ETA-23/0859, our isoweld® EPD and FM approved options are available.

The isoweld® system utilises the benefits of mechanically fixing, whilst provides a non-penetrating fixing solution to the membrane.

The isoweld-B induction welding tool operated by an SFS fastening expert.

What is induction welding?

Induction welding is an alternative flat roof fixing method for securing PVC, TPO and EPDM membranes. Flat roofs must withstand high wind loads, as such the secure attachment of thermal insulation and single ply membrane to the substrate is critical. Induction welding uses high-frequency electrical currents to heat metal plates, fusing them to the membrane itself.

Its speed, precision, and versatility make it a preferred fixing method for many installers.

How does isoweld® work?

To install use the isoweld system with a streamlined, repeatable approach, follow this 3 step process.

01

Position the membrane

The single-ply waterproofing membrane is placed over the specially coated load distribution plates which are secured to the substrate via a fastener or fastener/sleeve combination.

02

Heat the plate

An isoweld® tool is placed on the single-ply waterproofing membrane directly over the load distribution plate and heats the load distribution plate to a predefined temperature.

03

Secure the bond

Once the welding process has been completed, a magnet heatsink is placed onto the single-ply waterproofing membrane over the load distribution plate, securing the bond.

Product render of the isoweld-B battery powered induction welding tool.

New Advancement

Introducing isoweld® B

Innovation is at the core of SFS, we are continuing to find new ways to advance our technology and improve our customer's experience. Isoweld® is no exception, with 2025 seeing the launch of the next generation of isoweld® technology: isoweld® B.

The first of its kind, isoweld® B is powered by batteries, providing users with a cordless option.

  • Cordless battery-powered operation
  • Same welding performance as mains-powered unit
  • Enhanced mobility for large roof areas
  • Quick-change battery system
  • Integrated digital temperature control
  • Lightweight ergonomic design

Compatible product for use with isoweld®

Carbon Steel isoweld® Stress plate

Carbon Steel isoweld® Stress plate

  • Carbon Steel material
  • Stress plates suited for PVC, TPO and EPDM  membranes
  • Compatible with the FI-R-20n sleeve
  • ETA-23/0859, FM Approved and EPD approval.
Product Information
FI-R-20 fastener sleeve product render

FI-R-20

  • Heat resistant material
  • ETA-23/0859, FM Approved and EPD approval.
  • Optimised sleeve tip for reduced penetration force
  • Universal Sleeve design for various applications and combination
Product Information
BS-S-4,8 stainless steel fastener product render

BS-S-4,8

  • Stainless steel quality A4, 1.4401, AISI 316
  • Optimised shape of the bi-met drill tip, for effective drilling
  • High pull-out values with asymmetric fastener thread
  • ETA-23/0859 and EPD approval.
Product Information

isoweld®

Precision Induction Welding

The isoweld® fastening system uses induction welding to secure single ply membranes to dedicated stress plates, delivering a non-penetrating fastening solution. The innovative system increases installation efficiency, ensures security, and reduces overall project costs.

Download Brochure
SFS isoweld® induction welding fastening system tool

50%

Potential fewer fasteners

Cost savings advantage

3s

Welding time

Fast welding, speedy installation

20%

Potential savings

On the total install cost

40m+

Square meters

Successfully installed worldwide

The benefits of isoweld®

The Isoweld induction welding machine provides multiple benefits for efficient and high-quality welding.

Efficiency

  • Induction welding achieves secure welds in as little as 3 seconds, significantly speeding up installation
  • Membrane-compatible wheels improve roof manoeuvrability and productivity

Security & Reliability

  • Search and Find functionality keeps the tool aligned on the plate and prevents welding if misaligned to avoid incorrect or partial welds
  • Mechanical fixing supports pull-out testing and wind-load calculations

Ergonomics

  • Height-adjustable handles support an ergonomic working position and reduce the need to bend down
  • Improved installer comfort helps to reduce strain and supports productivity

Cost Efficiency

  • Field-fixed positioning enables even fastener spacing without membrane penetration and may require up to 50% fewer fasteners
  • Single membrane width with no cover strips reduces welding and material costs

See isoweld® in action

See the future of induction welding in action with a full introduction video and a real-world isoweld® B case study.

What is isoweld®?

The isoweld® system uses induction technology to weld single ply membrane to dedicated stress plates, securing it to the roof deck. The innovative system increases efficiency, ensures security and saves on cost.

The isoweld® system comprises of:

isoweld® induction tool

A user-friendly and ergonomic stand-up induction welding tool.

It contains integrated safety and security features, such as search & control functions, temperature & power compensation, quick & simple calibration process, ensuring proper and correct welds.

Hand welding tool

This has a flexible 6m cable, for use in narrow, vertical and tight roof spaces. It's used in conjunction with the isoweld® induction tool.

Magnet set

Set of 10 magnetic heatsinks, which are positioned on the waterproofing membrane over the FI-P stress plate to apply pressure and to dissipate heat. Extension rods included for working in an up-right position.

SFS Load distribution Plates

The FI-P-6,8 is suitable for an all-metal fixing application, whilst the FI-P-16,0 is usable with the FI-R-20 sleeves. There are 3 versions of the SFS load distribution plates, in 3 distinct colours, designed to be suitable with PVC, TPO & EPDM membrane types.

SFS FI-R-20 Sleeves

SFS FI-R-20 sleeves are from temperature resistant polyamide, making it suitable in induction welding applications. The FI-R-20 sleeves are designed with a low profile, to help prevent ghosting and has an optimised tip for easier installation.

SFS High Performing Fastener

SFS have a large range of fasteners compatible with the Isoweld® fastening system, available for all substrates.

The isoweld® fasteners and stress plates are covered under our Flat Roofing ETA-23/0859, our isoweld® EPD and FM approved options are available.

The isoweld® system utilises the benefits of mechanically fixing, whilst provides a non-penetrating fixing solution to the membrane.

The isoweld-B induction welding tool operated by an SFS fastening expert.

What is induction welding?

Induction welding is an alternative flat roof fixing method for securing PVC, TPO and EPDM membranes. Flat roofs must withstand high wind loads, as such the secure attachment of thermal insulation and single ply membrane to the substrate is critical. Induction welding uses high-frequency electrical currents to heat metal plates, fusing them to the membrane itself.

Its speed, precision, and versatility make it a preferred fixing method for many installers.

How does isoweld® work?

To install use the isoweld system with a streamlined, repeatable approach, follow this 3 step process.

01

Position the membrane

The single-ply waterproofing membrane is placed over the specially coated load distribution plates which are secured to the substrate via a fastener or fastener/sleeve combination.

02

Heat the plate

An isoweld® tool is placed on the single-ply waterproofing membrane directly over the load distribution plate and heats the load distribution plate to a predefined temperature.

03

Secure the bond

Once the welding process has been completed, a magnet heatsink is placed onto the single-ply waterproofing membrane over the load distribution plate, securing the bond.

Product render of the isoweld-B battery powered induction welding tool.

New Advancement

Introducing isoweld® B

Innovation is at the core of SFS, we are continuing to find new ways to advance our technology and improve our customer's experience. Isoweld® is no exception, with 2025 seeing the launch of the next generation of isoweld® technology: isoweld® B.

The first of its kind, isoweld® B is powered by batteries, providing users with a cordless option.

  • Cordless battery-powered operation
  • Same welding performance as mains-powered unit
  • Enhanced mobility for large roof areas
  • Quick-change battery system
  • Integrated digital temperature control
  • Lightweight ergonomic design

NBS Source Specification

View the full Isoweld® product specification directly from NBS Source, including technical data and compliance details for quick and easy referencing.

Compatible product for use with isoweld®

Carbon Steel isoweld® Stress plate

Carbon Steel isoweld® Stress plate

  • Carbon Steel material
  • Stress plates suited for PVC, TPO and EPDM  membranes
  • Compatible with the FI-R-20n sleeve
  • ETA-23/0859, FM Approved and EPD approval.
Product Information
FI-R-20 fastener sleeve product render

FI-R-20

  • Heat resistant material
  • ETA-23/0859, FM Approved and EPD approval.
  • Optimised sleeve tip for reduced penetration force
  • Universal Sleeve design for various applications and combination
Product Information
BS-S-4,8 stainless steel fastener product render

BS-S-4,8

  • Stainless steel quality A4, 1.4401, AISI 316
  • Optimised shape of the bi-met drill tip, for effective drilling
  • High pull-out values with asymmetric fastener thread
  • ETA-23/0859 and EPD approval.
Product Information