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ISL Brand

ISL Therm-A-Lock | Intumescent Lock Pack

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Product Code: HINGELOCK
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It has been proved conclusively that the ironmongery fitted to fire doorsets with ratings over FD30 introduces a great weakness to the door’s overall performance, unless some additional protection is applied over and above that afforded by the normal door edge intumescent strip.

Time and time again, doorsets fail fire performance tests. This is due to the premature burn through by the upper and mid-height positions, and whilst this has been recognized officially in BS 8214 (1990), there has been no specific guidance offered to specifiers and installers as to what type of intumescent materials to employ.

Pastes and mastics are messy and it is difficult to control the rate of application, intumescent screw plugs are time consuming to fit and the normal 15mm or 20mm x 4mm do not have the extra volume of material required for satisfactory performance. However, Intumescent Seals have developed a tailored solution to the problem with Therm-A-Lock which is a pre-sized backing pad of intumescent material that fits behind the lock set to create a fire door lock.

The Therm-A-Lock intumescent lock pack is produced from an exclusive LP material, developed as a low pressure intumescent sheet to withstand a full range of environmental conditions and flexible in nature for ease of installation. Therm-A-Lock should wrap around the lock assembly like a ‘jacket’ before inserting into the door leaf.

Therm-A-Lock provides fire resistance of 30 or 60 minutes when fitted to full size door assemblies and tested in accordance with BS 476 Pt. 22. We can supply intumescent sleeves to fit all regular UK lock case sizes of 63mm, 75mm and 100mm deep with a common height of 108mm and 56mm centres, generally manufactured to the dimensions given in BS 5872: 1980 figure. 4.

Therm-A-Lock intumescent lock pads are stocked in the following sizes; 130mm x 2100mm & 165mm x 85mm x 16mm and is supplied with 1mm thick self-adhesive. The LP material can be manufactured in either 1mm or 2mm thick and can be supplied in lengths or pre-cut to match any lock. Please call or email Firewise at +44 (0) 1223 839 727 or [email protected] for a bespoke size.

Brand: ISL

Use Case: Fire

Applications: Doors

Test Certification: BS 476 Pt. 22

Fire Rating: 30 Minutes, 60 Minutes

Material: Mono-Ammonium Phosphate

Finish: White

Fixing: Self Adhesive for Surface Mount

Included: 1x ISL Therm-A-Lock Intumescent Lock Pack, 1x Self Adhesive Backing

Length mm: 2100mm

Width mm: 85mm, 130mm

Thickness mm: 1mm, 2mm, 16mm

Date Added
ISL Therm-A-Lock Technical Data Sheet
18 October 2022
Technical Data Sheet
ISL Therm-A-Lock Fire Test Report
18 October 2022
Test Evidence

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ISL Therm-A-Lock | Intumescent Lock Pack
ISL Therm-A-Lock | Intumescent Lock Pack
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