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Polycor F/R Insulated DPC Cavity Closer
Data Sheet


Polycor F/R Insulated DPC Cavity Closer consists of a length of non combustible, flexible mineral wool slab fully bonded to a polyethylene damp proof course. The damp proof course has a 40 mm flange on each long side and a 100mm flange on one end.


Polycor F/R Insulated DPC Cavity Closers are a compression fit solution
designed to reduce cold bridging around door and window frames along with minimising sound transmission along cavities of external walls.


  • Fire, thermal and acoustic solution
  • Simple to install
  • Integral damp proof course
  • Maintenance free



10mm      25×100/165x1200mm
10mm      25×150/225x1200mm
20mm     35×100/165x1200mm
20mm     35×150/225x1200mm
30mm     45×100/165x1200mm
30mm      45×150/225x1200mm
40mm      55×100/165x1200mm
40mm      55×150/225x1200mm
50mm      65×100/165x1200mm
50mm      65×100/225x1200mm
75mm       90×100/150x1200mm
75mm       90×150/225x1200mm
100mm     120×100/165x1200mm
100mm      120×150/225x1200mm

[* Bespoke requests to customer specification available]

Standards and Performance

The mineral wool insulation achieves a fire classification of Euroclass A1 and has a thermal conductivity of 0.035 W/mK. The DPC conforms to BS6515 (1984).

Insulated DPC Cavity Closers conform to the 2000 Building Regulations (2006 edition).

The product has been independently tested adopting procedures and criteria from BS476 : part 20 : (1987) and achieved 1 hour fire resistance.


Polycor FR Insulated DPC Cavity Closer should be fitted during the building process prior to the installation of door and window frames.

This product should be fitted DPC side against the inner face of the outer brickwork, with one of the 40mm flanges folded against the door or window frame in the normal way, and with the other 40mm flange remaining flat against the inner face of the outer brickwork.

If more than one length of Insulated DPC Cavity Closer is required, or wherever there is a joint between two pieces they should be fitted with a flange at the bottom and with the next closer forming a close butt joint over the flange.

The top of the Insulated DPC Cavity Closer should be sealed to
the underside of the lintel or protected behind a cavity tray.

Handling / Storage

Polycor FR Insulated DPC Cavity Closers are supplied in strong polyethylene bags for on site protection. Care should be taken to keep the product dry prior to installation.

Some local delamination may occur during handling.
This does not detract from the performance of the product.

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