Nationwide Coverage

uk icon

Made in the UK

40 year icon

40 Year Heritage

unique icon

Unique Patented Products

warranties icon

Extensive Warranties

Revonate Not Replace - Industry-leading wooden window repairs

Wherever possible, Ventrolla tries to renovate and save the original windows. Preserving the unique heritage and charm of period timber windows really is a priority to us, and with the right care and attention, original timber window frames can provide a lifetime of enjoyment. So, where possible, we will always suggest renovation over replacement via our tried and tested Ventrolla Perimeter Sealing System (VPSS), while expertly repairing and replacing rotten sections with ease and finesse.

So, if your original timber windows are draughty, rattling, or inefficient, we're sure our industry-leading window renovation services can help bring your timber windows back to life. After all, there’s no denying that timeless timber window frames play a crucial role in defining the character of period building facades and their interiors –
so why should you or your client’s property be any different?

Window Repair Features

What makes our timber window renovations unique?

engineering icon

Patented products

award icon

Award winning designs

window icon

100,000+ window renovations

working icon

In-house manufacturing

van icon

Local expertise,
national coverage

Get in touch
sash bay window

Elegant, high-performance timber window repairs

Trusted heritage, nationwide coverage

From one timber window to 100 windows, our unique patented timber repair system is what sets us apart from the rest. Dedicated to making your life more comfortable, our renovation services are guaranteed to deliver the highest levels of insulation, performance, and style no matter the project size or location. Taking care of the entire renovation process from start to finish, our superior timber window repairs and renovations are guaranteed to:

  • Eliminate draughts & rattling frames
  • Reduce carbon emissions & energy bills
  • Comply with the latest Building Regulations
  • Preserve historic buildings for generations to come
  • Enhance kerb appeal & property value
Find Out More
timber window renovations

Bespoke wooden window repairs for Listed Buildings, Conservation Areas, and AONBs

Working closely with local conservation and planning officers, English Heritage, Historic England, Historic Scotland, and Cadw, you can trust in Ventrolla to revive and restore unique architectural features while simultaneously heightening historical value too.

Our highly skilled craftsmen eat, sleep, and breathe compliant timber window repair and restoration. From intricate wooden windowsill repairs to beautiful bay window draught-proofing and everything in between, they are experts in the local history, architecture, and geography of your local area, which are all considered in the estimate and workmanship.

See our case studies
sash window repairs

Is it worth restoring old wood windows?

Investing in historic timber window restoration provides intuitive homeowners, architects, and developers with a wealth of benefits, including:

  • Usually, the most cost-effective refurbishment option
  • Notably reduces energy bills & exterior noise
  • Ensures no loss of character
  • The best choice for listed buildings, properties in conservation areas & AONBs
  • Premium shutter options complement original windows further
  • Positive impact upon surrounding architecture
  • Contributes to sustainability in its widest sense
Get in touch

Our Process



The Ventrolla journey begins with a discussion with a member of our team and/or a detailed home or site design survey, to explore your ideas & devise a bespoke plan of action.



Once our team have finalised the plans, we will provide a comprehensive estimate for your works. Enquiry to estimate typically takes between 5 and 10 working days.



Ventrolla fuse traditional skills with modern technology. If you require new joinery, creating your unique product begins in our UK-based manufacturing facility, and takes between 6 and 10 weeks.



The utmost care is taken to deliver quality products and renovation works that exceed our customers’ expectations. Varying from area to area, Ventrolla lead times depend on how busy we are, and the work required. On average, our installation team will be on site between 6 to 18 weeks from the date your order is placed. We will advise guide installation dates when you place your order.



Our customers come back time and time again – when they move or if they’ve phased their works – all thanks to our exceptional customer service and after care. In the unlikely event that your Ventrolla products require expert attention, we’re always on hand.



Renowned for delivering outstanding quality, all our work comes with a minimum 5-year guarantee (subject to terms), for absolute peace of mind.

  • Specifications


Double glazed sash window units
(sashes only):

  • Slim 14mm (4/6/4) double glazed units
  • Planitherm Total+ glass (outer pane) and krypton-filled cavity
  • Centre Pane U-Value of 1.5 Wm²K
  • Total Window U-Value of 1.8 Wm²K

Full Ventrolla product listings are available on the RIBA Product Selector and NBS Plus websites.

Request a brochure
draught proofing

What our customers are saying

Ventrolla were able to beat all the other quotations that I received and answered queries quickly and informatively, making changes as required promptly and without fuss. I was kept informed throughout of lead times and manufacturing times. The real stars of the show were Rob and James who worked tirlessly and brilliantly as a team to repair sash boxes where required and install our new sashes. Thank you!


Everybody I dealt with has been super friendly, informative, and helpful. I received emails with updates on what was happening, etc. It has been a great experience from start to finish.


I used Ventrolla to renovate my sash windows over to years ago. When two of them finally collapsed, including a bay window the size of three full sized Georgian windows they were my first contact. The office staff, surveyors and the three fitters that did an amazing job installing them in less than two days were all excellent. The quality of workmanship and the standard of installation were first class, and the new windows look amazing. I will definitely be using them again as more of my windows will need replacing over the next few years.


This is the second property Ventrolla have restored my windows for me, and the this job was every bit as good as the first. 14 sash windows in a Grade II listed building installed/refurbed without a hitch in week. The team of 4 installers were lovely chaps, super efficient and tidy. All round another fabulous job done – thank you the Ventrolla Team


nbs partner
builders profile
british safety council
safety first
disclosure and barring service
Responsibly Sourced Timber Tree heart

Frequently Asked Questions

How does the Ventrolla Perimeter Sealing system (VPSS) improve comfort levels?

The main complaints we receive from customers tend to be about draughts, rattles, leaks, and heat loss from their windows. Our draught-proofing system closes the gap around the sashes, eliminating these issues whilst allowing the sashes to still travel smoothly past each other.

Do you offer an installation guarantee?

Yes, our work is guaranteed for 5 years.

How long will my window renovation take?

The time taken will vary depending on the result, e.g. your survey and the work we identify as needed. Typically, we work to a one-window-per-day time scale, although this can be adjusted, if necessary, to suit your requirements or our schedule.

Varying from installation to installation, our average timescale targets are

  • Enquiry to estimate: 5–10 days
  • Estimate to order: 30 days
  • Order to installation: 10–16 weeks

Can you fix window condensation?

The main way to combat condensation is to further ventilate your home (i.e. open your windows from time to time). The moisture in your home is caused by heating, bodies, etc. and it settles on the nearest cold surface, which is usually your windows. Double glazing units will be slightly less cold and therefore you may notice slightly less condensation, however, your home will also be better insulated, thus more moisture may be contained within your home.

What is the average cost of renovating a window?

It all depends how much work each window needs. For a more accurate estimate, please call us on 0800 0277 454 to arrange a free, no obligation survey.

How long does double glazing last in a house?

The lifespan of double glazing windows can vary depending on several factors, such as the quality of the materials used, the installation method, and the level of maintenance they receive. On average, double glazed windows can last between 10 to 20 years, although some high-quality units can last up to 35 years or more.

Regular maintenance, such as cleaning and lubricating the hardware, can help to extend the lifespan of your double glazed windows.

Are double glazed windows worth it?

Double glazed windows are definitely worth considering as they offer several benefits for homeowners. One of the main advantages of double glazing is that it can significantly improve the energy efficiency of your home. The two panes of glass create a layer of insulation that helps to keep warm air inside during the winter and outside during the summer, reducing heat loss and lowering energy bills.

In addition, double glazing can also help to reduce outside noise, making your home quieter and more comfortable. The insulating layer between the panes of glass helps to block out sound waves, which can be especially beneficial if you live in a busy or noisy area.

Got questions that haven't been covered? Visit our FAQs or speak to our friendly team today:

get in touch

What to do next

Subscribe to our Newsletter

Stay up to date with the latest news and tips from our Knowledge Hub.