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Casement window restoration service which transforms decayed and damaged windows, upgrading them and protecting them for the future. Casement window insulation not only improves thermal performance, it also protects the window.

Features and benefits:

  • Solves draughts and rattling.
  • Reduces dirt, dust and rain ingress.
  • Smoother, easier window operation.
  • Hidden, rebated seals, not surface mounted.
  • Tested for water permeability, air tightness and wind resistance.
  • Installed by expert window restorers.

General information

All bare timber surfaces are primed with one coat of preservative primer

Uniclass 2015 Wood window units (Pr_30_59_98_96)
Specification data
Product Reference

TRC Casement Window Renovation with High Performance Draught Proofing

Frame colour/ finish


Insert requirement from RAL classic range.


Insert requirement from TRC stain range.


RAL 9016 – Standard.

Glazing -

Not required

Double glazed

Ultra-slim and efficient.

Perimeter spacer bars

Insert requirement.

Sill replacement

Not required


Fittings -

Insert requirements, consult with manufacturer for information.

Colour/ Finish


Polished chrome

Satin chrome

Special order

Insert requirements, consult with manufacturer for information.

Standard product features


All bare timber surfaces are primed with one coat of preservative primer.

Timber repair:

Decayed and damaged timber is gently prised out from windows, frames and sills, retaining as much of the original wood as possible. Where decay is severe, sections of timber is replaced with new joinery work to closely match the original. Whole cills or cill fronts can be replaced seamlessly to match the original window profile.

The remaining timber is treated with a multi-stage epoxy resin repair system called Repair Care. Using specialist tools, the surface of the repair is carefully smoothed to match the shape of the original timber, so that it blends seamlessly. Finally, the window is stained or painted as required.

Draught proofing:

Draftfix system which typically uses a weather pile with a central fin, fixed into a plastic carrier which is rebated into the casement. The weather pile prevents dust and dirt ingress, and the central fin contributes to air tightness. All the seals are rebated into the casement, which means no unsightly, protruding, face-fixed seals.

Draught proofing is applied around the perimeter of the opening casement window, ensuring thorough, effective sealing while still allowing the window to open freely. Verified to BS 6375-1.

Perimeter sealing system performance:

  • Air permeability (to BS EN 12207): 600 Pa (Class 3).
  • Water tightness (to BS EN 12208): Result: 250 Pa (Class 6A).
  • Resistance to wind load test pressure, and frame deflection (to BS EN 12210: 2000 Pa (Class A5).
  • Weather tightness (to BS 6375-1): 2000.
  • Acoustic: Increases performance of a window by 6–10 dB (A).

Product Options

Sill replacement:

Whole sills or sill fronts can be replaced seamlessly to match the original window profile.


Comprehensive collection of casement window furniture available in elegant, classic styles to suit all eras. Casement stays, fasteners and locking devices available in a wide range of finishes, bespoke designs are available.

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