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Door edges and lippings

Hardwood lippings are generally applied to vertical door edges of most product ranges, although they can also be applied to top and bottom edges where required - for example where used externally. Timber species are usually selected to match veneers, as outlined in the doorsets materials & finishes section. Lippings provide protection to the edge of the door and specifically its face, as well as covering the door core. The Plasform Range utilises a postformed edge detail which conceals hardwood lippings.

Details of door edges for various situations are illustrated below.

Intumescents and smoke seals

Perimeter fire seals are essential to performance and form an integral part of the doorset fire rating, irrespective of stop size. There are three types available: intumescent, intumescent and smoke seal combined, and concealed intumescent. The first two systems incorporate exposed intumescent strips to the frame jambs and head as standard, whereas the concealed method houses the intumescent
strips behind vertical door lippings but exposed on top – this provides 30 minutes fire resistance only.

Generally, exposed intumescents are 10mm/20mm x 4mm for 30 minute performance or 2 no 15mm x 4mm seals for 60 minutes. Intumescent colour is determined by veneer selection and will be either maple or light brown. If doorsets are primed for paint white intumescents are supplied as standard.

Where Plasform doorsets have been ordered intumescents will be colour matched from the standard range available. Alternatively intumescent colour for primed or Plasform doorsets can be specified.

Where complete doorsets are being supplied, all necessary intumescent seals will be included to the frame as standard, in order to achieve the stated performance. However, the specifier needs to indicate whether the concealed method is required. In the case of pairs of fire-rated doors, a
combined intumescent and smoke seal will be incorporated at the meeting stile of the primary leaf corresponding with a plain intumescent in the secondary leaf.

Where doors only are being supplied, seals need to be specified precisely if required. If intumescents are to be fitted by others, they must comply with our fire certification requirements and the BWF-CERTIFIRE datasheet.

Concealed intumescent seals can be incorporated into the vertical edges of single doors but the intumescent in the top edge must be exposed and is positioned to run the full width of the door leaf. With pairs of doors the primary leaf will always feature an exposed combination seal at the
meeting stile.

Use of a combined intumescent and smoke seal instead of an intumescent only will provide smoke protection in accordance with BS 476 Part 31.1, ‘Requirement for Cold Smoke Protection’, providing the gap at the bottom of the door does not exceed 3mm. If it does, an additional threshold seal will be required.

The diagrams which follow indicate the positions of intumescents and seals for various fire ratings and
configurations. FD90 and FD120 doors are supplied as part of doorsets only, including the necessary intumescents.

Single action intumescents position FD30

Double action intumescents position FD30

Note: Intumescent detail may vary from that shown depending on performance and certification.

Thresholds

Thresholds may be needed for acoustic and smoke control applications to restrict below-door gaps, working in conjunction with appropriate door-mounted seals. Essential thresholds must be fixed parallel to the bottom of the door and may be screw-fixed directly to hard surfaces such as concrete or smooth vinyl.

For carpet or textured/profiled vinyl flooring, they can be fixed directly to floor screeds. Aluminium thresholds for acoustic purposes should be located on a hardwood packer (to suit the floor finish depth) with mastic to threshold/packer and packer/screed.

Note: Intumescent detail may vary from that shown depending on performance and certification.

Aluminium threshold