Nationwide Coverage

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Made in the UK

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40 Year Heritage

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Unique Patented Products

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Extensive Warranties

Advanced acoustic & insulating secondary glazing that never compromises on style

Preserving the unique heritage and charm of period timber windows really is a priority to us, which is why we offer industry-leading secondary glazing products as an alternative for listed buildings, conservation areas, and other properties subject to restrictive improvement regulations. Tailored to a wide range of property styles, we have over 35 years' worth of experience crafting and installing quality secondary glazing designed to enhance thermal efficiency and security and reduce noise pollution.

Secondary Glazing Features

What makes our secondary glazing unique?

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Reduced noise levels up to 80%

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Reduced heat loss up to 65%

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Bespoke traditional & heritage styles

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Custom fit to your property with care

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Local expertise, national coverage

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Preserve your building’s unique aesthetic with quality secondary glazing

Enlightening, discreet, warm & tranquil

Secondary glazing consists of a fully independent internal window fitted on the room side of an existing window. Secondary glazing delivers many of the features that modern double glazing provides without the extra hassle of trying to obtain planning permission.

Made from lightweight, slender aluminium frames, enjoying the sunshine and making the most of far-reaching views, whilst preserving your property’s exceptional character, is a straightforward process with secondary glazing installations by Ventrolla.

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Secondary glazing windows in two period-style ranges

Designed to seamlessly blend with the style of your property, our secondary glazing is purpose-built to suit all property and window types, and is available in six diverse variations;

  • Horizontal Slider
  • Vertical Slider
  • Hinged Unit
  • Fixed Unit
  • Lift Out Unit
  • Bespoke & Arched Units
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Traditional Secondary Glazing Features

  • Slim, discreet aluminium profile
  • Minimal sightlines
  • Easy access to primary glazing
  • A popular choice with homeowners

Heritage Secondary Glazing Features

  • Slightly thicker, heavy-duty aluminium profile
  • Perfect for small to large-scale commercial installations


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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.



Fusing traditional skills with modern technology, 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 manufactured products and renovation works that exceed our customers’ expectations. Depending on the project, our installation team will be on site between weeks 10 to 16.



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.

What our customers are saying

Thank you very much for an excellent job, by some of the nicest, most professional builders I have had working here for three decades.

Mrs Schecter, Kensington

Excellent service from the fitters. Extremely impressed with their tools and equipment to carry out the works. Certainly knew what they were doing. A welcome change

Mr & Mrs Kukk, Whitby

We were most impressed with the speed of your reply, the sympathy you had with the building’s integrity, the quality of your demo kit and the attention to detail in your quote. You are an excellent advocate for your company.

Mary Sherwood

Hi Jarrod I refer to our recent telephone conversation and as agreed, attach hereto formal confirmation of my satisfaction with the works undertaken by your company. Ian and Lee are a credit to your business and from my discussions with them, I can tell that they really enjoy being part of the Ventrolla team.


Frequently Asked Questions

I live in a listed building / conservation area / AONB - can you work on my property?

In these cases, secondary glazing is an ideal alternative. We have completed lots of work over the years on listed properties and those within conservation areas and Areas Of Outstanding Natural Beauty (AONB). Working closely with local conservation and planning officers, English Heritage, Historic England, Historic Scotland, and Cadw, you can trust in Ventrolla to reinstate and sustain unique architectural features whilst simultaneously heightening historical value too.

Will secondary glazing reduce outside noise levels?

Independently tested and proven to significantly reduce sound intrusion, our high performance secondary glazing can reduce noise levels up to 80% and heat loss up to 65%.

Do you offer an installation guarantee?

Yes, our work is guaranteed for 5 years.

What is the average cost of renovating a window with secondary glazing?

It all depends on 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 it take to install secondary glazing?

The time taken will vary depending on the result e.g., your survey and the work we identify is 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 quote: 5-10 days
  • Quote to order: 30 days
  • Order to installation: 10-16 weeks

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

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