The VPSS was created by Ventrolla’s founder, Robert Tunicliffe. Drawing on his experience designing gaskets and seals for Ford Motors, this innovative window seal has evolved over the last 40-years into a precision-manufactured system. Thousands of homes across the UK already have it fitted and are benefiting from a less draughty home.

What are the benefits of the VPSS?

Essentially, this is draught-proofing technology, which acts as a barrier to cold air which is entering the home. VPSS brings with it a selection of other plus points, too – and has been tested to offer the following benefits:

  • It prevents rattles
  • Stops water and dust ingress
  • Helps to cut down external noise being heard in your home, and
  • Keeps warm air in to help reduce energy bills – the VPSS has been independently verified to improve the Window Energy Rating (WER) by up to 30%


A new Venetian sash window, by Ventrolla

A new Venetian sash window, by Ventrolla


If your sash or casement windows are in need of repairs or renovations – or you are looking for replacement windows to mirror existing ones, you may be interested to know that the VPSS is usually fitted as standard.


Why Choose VPSS?

1. Energy Efficiency Redefined

Say goodbye to drafts and energy loss! VPSS is designed to create an airtight seal around windows and doors, preventing heat or cool air from escaping your space. This translates into substantial energy savings and a reduced carbon footprint.

2. Enhanced Comfort

Experience a new level of comfort with VPSS. No more chilly drafts or unwanted noise disturbing your peace. Our sealing system ensures that your living or working space remains cosy and quiet, enhancing your overall well-being.

3. Protect Your Investment

Windows and doors are significant investments in your property. VPSS helps protect that investment by preventing water ingress, and reducing the risk of damage to frames and sills. Extend the lifespan of your windows and doors with our advanced sealing technology.

4. Tailored for You

We understand that every property is unique. That’s why VPSS is customizable to fit various window and door styles. Whether you have traditional sash windows or modern casement windows, Ventrolla has the perfect sealing solution for you.

5. Seamless Integration

Our perimeter sealing system seamlessly integrates with your existing windows and doors, preserving the aesthetic appeal of your property. Upgrade your energy efficiency without compromising on style.

Avoid renovationAvoid renovation mistakes with a Ventrolla window's professional mistakes with a Ventrolla window's professionals

Avoid renovation mistakes with Ventrolla

How It Works

  1. Comprehensive Assessment: Our experts conduct a thorough assessment of your windows and doors to identify potential gaps and areas of improvement.
  2. Bespoke Solutions: Based on the assessment, we provide tailored solutions to address specific sealing needs, ensuring maximum effectiveness.
  3. Professional Installation: Our skilled technicians install VPSS with precision and care, ensuring a seamless integration that complements the existing architecture.
  4. Quality Assurance: Ventrolla is committed to delivering excellence. Our VPSS undergoes rigorous quality checks to guarantee optimal performance and durability.

Ventrolla Specification VR90 & VPSS

The Ventrolla system consists of two parts. The first phase is the renovation process which treats the wood and ensures the window is fully operational. The second phase is the performance upgrade, by installing our unique draught-proofing system, the Ventrolla Perimeter Sealing System (VPSS).


Phase 1 – Window Renovation

Ventrolla has developed a unique Wood Repair System (VR90) that has been designed to extend the life of wooden windows and doors.

VR90 wood repair is a two-part epoxy resin designed to impart the original strength to tenon joints and to fill cavities in sills, which it achieves through bonding with the original timber.

The system’s core benefits are:

  • It retains the majority of the original timber
  • Provides long-lasting repairs
  • Fast acting so minimises standing time
  • Reduces Carbon Footprint of repair
  • Enables existing profile to be matched In the event of excessive deterioration or if beyond economical repair, we replace the timbers, as required.

Application All windows are inspected and surveyed prior to quotation and commencing work. At installation, sashes are removed and the condition of the timber, glass and pulleys are fully assessed.

  • Decaying wood is removed back to the sound timber
  • VR90 WS stabiliser is applied to provide anchorage
  • VR90 filler is applied to fill gaps/joints and moulded to match the window profile
  • All sash cords are replaced and the pulleys serviced ensuring smooth operation

NB: In the case of larger repairs or where economics dictate, we splice in new timber, or, in the case of a rotten sill, we can replace it completely.


Phase 2 – Performance Upgrade

The Ventrolla Perimeter Sealing System (VPSS) has been specifically designed to be installed into any shape or size wooden window or door.

The system upgrades the performance of original wooden windows and doors without affecting either their appearance or character.

As shown in Diagram A below, the system is installed to provide a seal on all faces and becomes an integral part of the window or door.


Diagram A

Ventrolla Renovated Window

Ventrolla Renovated Window


The system’s core benefits are:

  • Virtually eliminates draughts and leaks
  • Eradicates sash rattle
  • Improves Window’s Energy Rating by up to 30%
  • Helps reduce noise problems
  • Ensures smooth operation of the window
  • Recognised by English Heritage, Historic England, Historic Scotland and Cadw
  • Application

A Perimeter Sealing System using a Weatherfin two-piece parting bead, compromising of a pile carrier fitted into a U-section, is installed in and around the sashes.

The sealing system:

  • Conforms to BS 7386: 1997
  • Conforms to BS EN 12207: 2000 and BS6375-1: 2009, Class 3
  • Is manufactured from multifilament polypropylene yarn that is silicon-treated to be water-repellent and UV-stabilised
  • Can be supplied in any colour (additional cost may apply)

The sealing system is installed to the top of the box, mid rail, bottom rail, parting bead and staff beads.

The sashes are weighed and the weights are adjusted to ensure the window is correctly balanced and operates smoothly.

All exposed and bare wood is painted with one coat of white acrylic primer to BS5082.

The sashes are reinstalled and staff beads fitted (if the easy-release Sash Removal System is being installed removable staff beads are fitted and corked).

Windows are then checked for smooth operation.

Independent Testing:

  • VPSS achieved the highest requirement of BS6375-1 2009, Class 3 (Tested to 600 Pa)
  • VPSS provides up to a 30% improvement in a Windows Energy Rating (WER)
  • Air change rates were reduced to 0.4 air changes per hour
  • Noise reduction levels of up to 6-10 dB(A) range
  • Has been independently tested and proven to fall within the 6 to 10dB noise reduction range


Transform Your Space Today!

Take the first step toward a more comfortable, energy-efficient, and elegant living or working environment. Contact Ventrolla today to schedule a consultation and discover how our Ventrolla Perimeter Sealing System can transform your space.

Ventrolla – Redefining Comfort, One Seal at a Time.

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