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Thermo-loc Standard Cavity Closer and Multi Cavity Width Closer

Economical and universal cavity closers to close the cavity at external doors, window jambs and sills to provide thermal insulation and prevent damp and cold bridging.

Rigid and lightweight UPVC profiles fitted with expanded Polystyrene insulation material (0.038W/mk).

LABC Registered Detail status provides the assurance that this range has been rigorously assessed for compliance with all relevant building regulations and standards across England, Wales and Scotland.

Available to suit cavity widths from 50 to 300mm.

The multi cavity width closers are the solution for projects with unknown or varying cavity widths:

  • pre-grooved insulation to offer cut lines for cavity widths of 50 to100mm and 100 to 150mm.

Quick and simple to install.

Supplied in convenient 2.4 metre lengths.

View product range & add to quote

Features & Benefits

  • Supplied in convenient 2.4 metre lengths
  • Quick and simple installation
  • Profiles can be trimmed to the required length using basic hand tools
  • Rigid profile extrusion allows both a first and second fix
  • Suitable for all frame and sill positions and materials
  • Provides an effective DPC and thermal barrier between the frame, inner and outer wall leaf
  • Exceeds the minimum thermal resistance path of 0.45m2K/W stipulated in Robust Details 'limited thermal bridging and air leakage
  • Components are available to make up ‘on-site’ frame formers
  • Durable and resistant to decay

Applications

  • To close openings in cavity walls, such as external walls and windows
  • Suitable for all frame and sill positions and materials
  • Can also be used to pre-form openings when the door and/or window frames are to be installed at a later date

Technical Information

  • Expanded Polystyrene insulation - thermal conductivity - 0.038W/mK
  • Exceeds the minimum thermal resistance path of 0.45m2K/W stipulated in Robust Details 'limited thermal bridging and air leakage'
  • Global warming potential depletion level: <5
  • Insulation Ozone Depletion Level: 0
  • BRE Green Guide Life Cycle Assessment: A+
  • BRE Document ‘Thermal Insulation: avoiding risks’ and Robust Details stipulate: ‘When a window or door frame is set back behind the inner face of a dense outer masonry leaf, it should overlap an insulated closer by a minimum of 30mm for BRE exposure zones ‘Sheltered to Severe’; but fully rebated (check reveals) for zones ‘Very Severe’

Specification

  • Fire rating: No
  • Acoustic performance: N/A
  • Insulation material: Expanded polystyrene (EPS)
  • Thermal conductivity:  0.038W/mK
  • Global warming potential depletion level: <5
  • Insulation Ozone Depletion Level: 0
  • BRE Green Guide Life Cycle Assessment: A+

How to Order

  • Estimate the total length of cavity closer required and divide by 2.4m to identify the correct number of units required (if ordering our standard cavity closer lengths)
  • Order the correct number of individual lengths so that there are no joint pieces
  • To use as window formers allow two corner formers (CCFORMS's) per opening, to support the closer in the lower corners
  • Fixing ties are available for secure fixing if required
  • Allow for ties to be fitted at 450mm centres

Installation Advice

Can be used in both first and second fix applications:

First Fix Installation

  • Cut the cavity closer into required lengths allowing the jamb section to overlap the sill section to butt the underside of the lintel
  • In first fix applications, the cavity closer should be nailed to the jamb/sill of the door or window frame and the whole assembly built in as work proceeds
  • Alternatively the closer can be built in sections using fixing ties as work proceeds or pre built to act as an opening former by using a timber brace and corner forms
  • Fixing ties are available for secure fixing if required
  • Allow for ties at 450mm centres

Second Fix Installation

  • For second fix applications, the cavity closer is pushed into the open cavity after building work is complete
  • The compressible nature of the exposed insulation material is used to create a friction fit into the cavity, or alternatively the insulation must can be trimmed to fit using a sharp knife
  • Joining 'off cut' sections should be kept to a minimum and not carried out to sill sections.
  • Sections are joined by mitre cutting the closer profile to allow the downward cut to run away from the jamb
  • Insulation should be extended from the lower, closer profile to allow this to slot into the upper profile to maintain a rigid section
  • All overlaps to be tape sealed
  • When installed in conjunction with a cavity closer, the back of edge of the window/door frames should be set back at least 30mm behind the inner face of the outer leaf to meet thermal requirements whilst ensuring that the front edge of the frame remains over the outer leaf
  • A smaller set-back may be possible, if a satisfactory hydrothermal assessment using BRE Information Paper IP/06, shows the thermal requirements are met
  • The junctions between the wall and the front and back of the window/door frame must be effectively sealed

Quality, Standards and Regulations

  • LABC Registered Detail product range
  • NHBC Standards
  • Building Regulation Approved Document Part C (2004)
  • Building Regulation Approved Document Part L1A and L2A (2013)
  • Complies with Robust Details ‘limited thermal bridging and air leakage’
  • Satisfies BRE document ‘Thermal insulation: avoiding risks’
  • Meets all relevant British Standards
  • Conforms to the Montreal Protocol
  • Manufactured to BS EN ISO 9001
  • Manufactured to BS EN ISO 14001

Material and Colour Choice

  • Rigid profile extruded in white UPVC
  • Supplied in 2.4 metre lengths
  • Expanded white Polystyrene insulation 0.038W/mk
  • Standard cavity options available 50mm–150mm
  • Wider cavity widths available to order
  • nbs plus
  • riba

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