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Specialist Sash Window Renovation and Performance Upgrade

Specialist Sash Window Renovation and Performance Upgrade

Ventrolla Sash Window Specialists Third party certifications:
  • BBA Agrément Certificate

    BBA Agrément Certificate

    Certificate type

  • BSI Kitemark

    BSI Kitemark

    Certificate type

  • QA Certificate

    QA Certificate

    Certificate type

Sash window renovation (timber).

Jump to:
+44 (0)1423 859323 www.ventrolla.co.uk


Ventrolla offer a sash window renovation service that negates the need to fully replace existing timber sash windows. This process involved renovating the existing windows and then installing Ventrolla's unique Perimeter Sealing System, so that all the charm and original character of sash windows can be retained.

Traditionally, a sash window requires a 3 mm gap around the sashes for functionality. Inevitably, this gap allows in draughts, dust and noise and is the source of annoying rattles. The installation into each window of the patented Ventrolla Perimeter Sealing System (VPSS) seals this gap and actually improves on the original by:

  • Eradicating rattles.
  • Eliminating draughts.
  • Minimizing dust and dirt ingress.
  • Increasing the energy efficiency.
  • Reducing external noise.

All work is done from inside the building meaning no need for expensive scaffolding. Windows are always left secure and weatherproof overnight.

General information

Uniclass 2015

Pr_30_59_98_96 Wood window unitsPrimary


L10/10 Wood windows

L10/210 Wood windows

Specification data - Wood window units

Product Reference

Specialist Timber Sash Window Renovation and Performance Upgrade

Sash removal system

Not required


Sill replacement and lower box assembly

Not required



Not required

Replace existing

Standard product features

Renovation and performance upgrade service:

This service includes:

  • Staff beads, parting beads and sash cords removed and discarded.
  • Sashes are eased by removing excess paint build-up, released and brought into the building.
  • Adjustments made to ensure min 3mm gap between upper sash face and parting bead face.
  • Mid rail and lower rail of bottom sash routed to profile of pile carrier.
  • Pile carriers fitted into the mid and bottom rails of lower sash and the new staff beads.
  • Where specified, Ventrolla Sash Removal System (SRS) is fitted - sash cord brake and detachable sash cord holder threaded on to each new sash cord. Sash edges routed to allow mounting of invisible SRS.
  • Ventrolla parting bead snapped into the new U Section installed into the existing parting bead groove.
  • Weatherfin pile weather-stripping (draught proofing) size selected and inserted as appropriate to width of gaps to be sealed.
  • Sash weights are adjusted to balance sashes.
  • Sashes re-hung and checked to ensure easy sliding.
  • New staff beads mitred or butt jointed and fitted by pinning, brass screw and cup, or easy release clips.
  • Exposed bare wood is painted with white acrylic primer to BS 5082.

Perimeter sealing system performance:

  • Air permeability: To BS EN 12207 Class 3 and BS 6375: 1-2009 (600 Pa) to withstand 71 mph winds, independently assessed by British Board of Agrément (test report number 2756).
  • Draught strips: Tested to BS 7386.
  • Sound insulation: Independently tested and proven to fall within the 6–10 dB noise reduction range. Performance verified by Hanns Tucker Acoustic Engineers.

Ventrolla Wood Repair:

Ventrolla wood repairs are undertaken using Ventrolla VR90, formulated to give long lasting wood repairs beyond those normally carried out using conventional polyester wood fillers. VR90 is a patented two-part resin system and is designed to be used to impart the original strength to sash tenon joints, to fill large cavities in sills and to act as a powerful adhesive. It completely bonds with the parent wood and flexes when the wood contracts or expands. To achieve this bond, all decayed wood is removed exposing only sound wood. This is then stabilised using VR90 WS solution which penetrates the wood fibres to attain the permanent anchorage for the subsequently applied VR90 filler.

Product Options

Sash removal system:

The Sash Removal System is a unique hidden system which allows the quick and easy removal of both top and bottom sashes internally. Staff beads can easily be detached from the window giving access to the bottom sash. Using the plastic cord holder, the sash cord can be unclipped from the window which allows the bottom sash to be completely removed. The parting beads can also be removed, allowing access to the top sash. The Ventrolla sash removal system allows all components of the window to be removed internally and brought into the building for convenient maintenance and painting, thereby avoiding the need for external scaffolding.

Sill replacement and lower box assembly:

Replacement sills can be provided to match original profiles. The original bottom section of the box linings is removed and Sill trenches are cut, the outer and inner linings are spliced to facilitate a flush and water tight finish.


A wide range of specialist locks and catches are available.

Seal Shuts:

Windows can be sealed shut internally and externally with the Ventrolla Sealing and Pointing system VS10.

Third party certifications

  • Air permeability: tested to BS EN 12207 Class 3 and BS 6375 (600 Pa), test report 2756 : Weatherfin Pile (Draught proofing) testing
  • Draught Strips (Weatherfin Pile): Tested to BS 7386
  • Hanns Tucker Acoustic Engineers : Sound Insulation: Independently tested by and proven to fall within the 6–10 dB noise reduction range (tested on single glazed sashes)

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