by Tom Wright, Managing Director of George Barnsdale

The Future Buildings Standard which is looming over the horizon in 2025 is likely to mean a big increase in the use of triple glazing in order to meet the lower U-values that will be required. However, specifiers are starting to consider vacuum glass as an alternative but which is better? Well, it depends….


What does the Future Buildings Standard say about u-values?

The Government has outlined its plans to deliver a “zero carbon ready” building strategy through its Future Buildings Standard. It aims to ensure that no new buildings from 2025 will require further retrofitting, with an uplift in energy efficiency standards, improved ventilation and requirements to mitigate overheating in residential buildings. A start was made on this last year with the changes to building regs and parts F, L and O.

Following public consultation, a Notional Building Specification has been developed which states that window U-values will need to be 0.8 (W/m2.K) down from 1.2 (W/m2.K) currently. Doors will need to be 1.0 (W/m2.K) from 1.2 (W/m2.K) (where more than 60% glazed)

This is likely to lead to triple glazing becoming the norm in most windows for new buildings or retro fits that want to achieve the highest performance.


What is triple glazing?

 Very simply, triple glazing is an extra pane of glass added to the two used in double glazing but the benefits can be great. Up to now, many of our clients have opted for triple glazing in areas where they require high acoustic performance, with this comes much better thermal performance, saving money on fuel bills.


What are the advantages of triple glazing?

  • Excellent thermal performance that meets the new Future Homes Standard, will save you money on heating
  • Great acoustic performance – ideal for blocking out noisy roads, aircraft noise etc
  • Better security – thicker units are harder to break
  • Can help to reduce condensation

What are the disadvantages of triple glazing?

  • It costs more than double glazing but usually not as much as vacuum glazing.
  • The windows are heavy which means they require chunkier frames and stronger fixings, all of which increase the price further.
  • Aesthetically, some people dislike the look of the triple glazed windows because they aren’t as sleek as single or double glazed ones.
  • Reduces the amount of heat from the sun limiting thermal gain. Harnessing solar energy is something homeowners have done for centuries and this is harder with triple glazed units.

What is vacuum glazing?

Vacuum glazing takes two pieces of glass with a tiny gap (0.1mm in the case of Fineo) and removes the air to create a vacuum.

They used to have unsightly plugs where the air was extracted but the latest technology means this is no longer the case. Ultra thin from as little as 7.7mm compared to 44mm for triple glazing, it’s great for listed historic properties or new builds looking for a sleek slimmer aesthetic.


What are the benefits of vacuum glazing?

  • 3-4 times thinner than triple glazing, looks more like single glazing
  • Same thermal performance as triple glazing. Fineo states 0.7 W/(m2K) which is better than the target the Government is aiming for in the Future Homes standard.
  • Lasts longer – because it doesn’t have gas between the panes which can leak over time
  • Better solar gain – allows more sun heat into the room helping reduce energy bills
  • Much lighter than triple glazing
  • 15% more light is allowed into the room compared with triple glazing
  • Environmentally better – much lighter saving on transport and less product used plus last longer so less need to replace
  • Great acoustic performance
  • Better aesthetically especially for historic properties, listed properties and modern contemporary builds that want to avoid heavy frames and fixings
  • Easier to install

What are the disadvantages of vacuum glazing?

  • Typically it is the most expensive option compared with double and triple glazing, this is thought to be due to there being no UK manufacturers making it and the inherent cost of the materials, some use silver for example
  • Low impact resistance – where micro pillars are used it can put high stress on the glass.

How much does vacuum glazing cost?

Vacuum glazing can cost up to 60% more than double glazing and around 35% more than triple glazing*.

*Prices may vary depending on size and spec.


So which should builders and architects choose from 2025?

Inevitably, it will end up coming down to price in most cases. We predict that most people will opt for triple glazing unless something drastic happens to the price of vacuum glazing, which may happen as the product becomes more popular and their production efficiencies improve. However, for anyone looking to balance the new regulations with heritage detailing, vacuum glass is the option that makes this possible.

“We are getting more and more enquiries about vacuum glass from architects and specifiers who like it for its performance and great aesthetic qualities, but often value engineering means they have to fall back on triple glazing.”




Now it’s time to lift and slide our product range with Comar 7P.i LS+. Innovative lift and slide gearing provides smooth operation for door configurations up to 12 metres wide and 3 metres high, creating true glazed sliding walls. From one system Comar 7P.i LS+ provides delivered solutions, for the summer months maximise the opening space with the three-track slider which creates two thirds clear opening, whilst in the winter the lowest U-values keep out the cold.

Innovation comes from Comar 7P.i LS+ offering unique solutions from one system, which means that with the same profiles you can provide lift slide or straight rolling gear, standard or slim interlock, enhanced performance with the inclusion of thermal foam and double or triple track configurations.

Optional slim interlocks maximise the homeowners view out when the doors are in the closed position keeping the slim sightlines of Comar 7P.i LS+ doors with the reassurance of the lowest U-values, so even in the coldest winter months daylighting is maximised and warmth assured. For a standard CEN size set of doors U-values are down to 1.4 with a 1.0 centre pane and using glass technology and Comar’s Enhanced Thermal Foam U-values of 0.74 are achievable.

The real advantage of this system is it’s smooth and easy lift operation, it’s ease of operation for sliding doors means that there is no alternative; it really is a lift slide life for all members of the family. Another advantage is the ability to lock the door in an open position anywhere along the track which means that the homeowner can open the door for ventilation without the risk of small children and toddlers exiting the doors.

For our fabricator and trade partners, Comar Systems utilises multi-function profiles which means that from a minimum stock all configurations of this feature laden system can be fabricated. Installers with the unique Comar Easyfit components minimise time on site and disruption to the home owner whilst maximising returns.

The Comar 7P.i Lift and Slide was developed to ensure a highly engineered solution that offers market leading performance. Feedback from the UKAS Accredited Test House was “it is the best they’d ever seen”, as it passed BS6375 Parts 1, 2 and 3 with no water leakage at 1050Pa. The hardware, has been tested to over 50,000 open and closing cycles.

As Secured by Design is now being incorporated into some region’s Planning conditions and BREEAM Assessments, Comar 7P.i LS+ passed the new stringent PAS24:2016 and holds a Kitemark for Enhanced Security to enable sub-contractors to provide an SBD Licensed product to discerning customers.

Glazing technology advances every day with new triple glazed units providing ever lower centre pane values, acoustic glasses to meet enhanced performance criteria are widely specified, Comar 7P.i LS+ now provides a future proof solution with a glazing pocket of up to 57mm. With a simple change of gasket and beads the Comar 7P.i LS+ provides this flexible solution for all your glazing needs.

For further information please contact Team Comar on, call 020 8685 2318 or visit

As one of the world’s oldest and most famous motorcycle manufacturers, Royal Enfield is known for creating modern classics and the company’s cool and contemporary style has inspired the design of a striking new technology centre in Leicestershire, which features a range of aluminium glazing solutions from Senior Architectural Systems.

Designed by LE1 Architects, the highly glazed façade of the impressive two storey research and development facility has been created by leading fabricator and installer Unique Window Systems Ltd for main contractor Stepnell.

With the need to maximise the flow of natural light whilst ensuring a comfortable internal working environment a key requirement, the attractive slim sightlines and enhanced thermal performance of Senior’s popular SF52 aluminium curtain wall system was the perfect choice for the building’s dramatic glazed entrance. To complete the fenestration package, Senior’s slim profile thermally-broken SPW300 aluminium windows were also specified, alongside Senior’s high-performance SPW500 and SPW501 aluminium doors which are ideally suited to high traffic applications.

Having successfully worked with Senior Architectural Systems on previous contracts, Unique Windows Systems Ltd recommended the use of Senior’s products for this high-profile scheme where achieving the desired aesthetics and performance was paramount. The strong yet slim profile of Senior’s SF52 aluminium curtain wall and SPW300 aluminium windows have helped to create the sleek, modern finish that the architect and client desired, with the low U-values offered by both systems also contributing to the overall energy-efficiency of the building.

Commenting, Patrick Marston, marketing manager at Unique Windows Systems Ltd said: “Senior Architectural Systems provide an excellent range of aluminum products for us to fabricate from. We often have complex budget and performance requirements from our customers to consider and Senior have a portfolio of products that means we can offer our clients an array of options to best suit”.

Located on the site of a former airbase in Bruntingthorpe near Lutterworth in Leicestershire, the new technology center for Royal Enfield is set to play a vital role in the manufacturer’s long-term product development strategy and as well as providing new office and design space, also includes state of the art facilities for the testing of new motorcycles.

For more information about Senior, visit

Combining superior thermal performance with minimal sight lines, Senior Architectural System’s SF52 aluminium curtain walling is helping to attract customers to a new flagship showroom for kitchen manufacturer Magnet.

Fabricated and installed by Aire Valley Architectural Aluminium Ltd for main contractor Castlehouse Construction, the SF52 curtain wall was specified as a toggle structural glazing system which thanks to its slim 52mm profile, provided the perfect solution to achieving a façade that features uninterrupted large expanses of glazing and an attractive flush finish.

The thermal performance of the SF52 system has also been enhanced through the use of double-glazed low emissivity glass, helping to contribute to the overall energy-efficiency of the building and the creation of a comfortable internal environment.

Senior’s curtain walling has been further complemented by the use of its thermally broken SPW500 commercial doors and SPW600 windows which together help to provide a light and welcoming space for customers.

Located in Leeds, West Yorkshire, the new flagship showroom for Magnet has been designed by LoRoc Architects and also features a new trade counter, office and warehouse facility.

With a wealth of experience in delivering high-quality solutions for commercial and retail applications, Senior curtain walling and glazing systems have been designed to help specifers working in this market meet the required environmental requirements by creating high-visibility shop frontages that minimise solar gain to create a comfortable consumer experience.

For more information about Senior, visit

(Photo by: Eric Sempé – SPIKSTUDIO)

The redevelopment of Paris’ Macdonald Warehouse has transformed an urban logistics building into a vibrant and contemporary neighbourhood, using bespoke glazing systems from Reynaers.

This project integrates into The Grand Urban Renewal Project; Paris’ wider efforts to provide more homes and inject life into neglected areas that are cut off by industrial facilities and infrastructural networks. An industrial barrier in itself, the ‘Macdo’ was designed in 1970 by Marcel Forest. The impressive structure spans over 600m in length, earning it the nickname ‘une tour couchée’, or ‘the horizontal skyscraper’.

Pleated facades

Key factors in specifying a range of Reynaers products for lots N5 and S6 of the design were performance, costs and technical evaluation. The CF 77 system combines high insulation and comfort with visual appeal. It is a highly versatile product, with a range of available opening types and threshold solutions. The folding elements with hidden gaskets create a particularly clean appearance, proving to be both efficient and aesthetically pleasing for ceiling-high, foldable doors.

The clean, sharp design of Reynaers windows integrates perfectly with the rhythmically extruded façades. This pleated façade was designed by FAA and XDGA, which wraps around the entire ground floor, the bridge building across the tramline as well as the exterior spaces and two blocks of assisted rental housing.

Architect Milena Wysoczynska, Project Manager at Paris-based XDGA-FAA, said: “Seeking a simple yet strong solution, we developed a single pattern for both blocks, with three-dimensional panelling that reflected the sky and added depth to the façade.”


A key concept in the renewal project is desénclavement, or ‘opening up,’ making the area less isolated and more accessible.

Once considered ‘ugly and difficult,’ the Macdo was developed and built upon by fifteen French and international teams. Co-ordinator Floris Alkemade, the Netherlands’ Chief Government Architect, explained that their aims are to respect the building’s heritage and enhance it with contemporary elements.

Alkemade, along with Belgian architect Xaveer de Geyter, established design guidelines to strike balance between coherence and creative freedom amongst the different plots. The result is a tidy North façade which overlooks the boulevard, juxtaposed against the more colourful and spontaneous South façade which overlooks a new train station and gardens.

With the residential aspect divided neatly into private and social housing, aesthetic standards ensure that no visible distinction can be made. As one of the biggest “live, work, play, shop” venues in France, the Macdonald Warehouse will offer more than 1,000 homes, expansive space for offices, shops and communal activities as well as two schools, a gymnasium and a bank across an incredible 210,000m2 of floor space.

Caisse des Dépôts et Consignations, a public sector financial institution, funded the €240 million development. Camille Picard, Managing Director of Paris Nord EST at the Caisse des Dépôts, said: “The scheme has a direct influence on the entire area; it enables everything that is happening in the neighbourhood. Without it, the construction of a new development zone across the street wouldn’t have started as they would struggle to sell flats and offices looking out on a warehouse.”

Lead architect: OMA, Paris
Local architects and project coordinators: XDGA + FAA (lots N5 and S6), Brussels
Contractor: Sicra, Chevilly-Larue
Investor: Caisse des Dépôts, Paris
Fabricator: Alu Concept, Chilly Mazarin
Reynaers system: CF 77

SMARTGLASS Dynamic, powered by SageGlass is a new glazing technology which has been hailed as a revelation. SMARTGLASS allows you to switch from clear glass through three progressively darker tints, giving you more control over both heat and light levels – all in a matter of minutes. The various shades of blue tint help to reduce glare and allow for a relaxed environment, no matter what the weather is doing outside.

Developed in the US and only recently arriving on UK shores, SMARTGLASS is currently available for residential homes via a range of lantern roofs, with full conservatory and bi-folding door products due to be available at a later date. SMARTGLASS is also ideal for offices and commercial buildings, especially where meetings take place and where screens suffer from glare.

SMARTGLASS offers three basic tint levels. The clear state is indistinguishable from normal glass and will let the same amount of light into the property. This tint level is ideal for darker winter days and for when a lot of light is required.

The full tint, at the opposite end of the scale, blocks 96% of the sun’s rays and reduces light transmission to just 1%. This full tint stage is ideal for very bright summer days, or where glare is a problem when reading or using technology. The blue hue creates a calming and relaxed space.

There is also a choice of intermediate states which allow you to tailor the perfect amount of incoming light. The glazing is tinted via a switch, which allows you to fully customise the light levels to best suit your needs.

SMARTGLASS Dynamic, powered by SageGlass works in a very simple and effective way. The glass itself is covered with layers of electrochromic coating. This is practically invisible to the naked eye and when in the clear state, this glass will simply look like ‘normal’ glazing. The layers of coating control the tint levels by allowing the lithium ions and electrons to travel through the layers when a low voltage is applied. When the ions and electrons are all transported to one layer of the coating, a dark tint is observed. As soon as the voltage polarity is reversed, the ions and electrons will travel back to their respective layers and the glass appears clear.

The voltage required is low (less than 5V DC) and is easy to install; just a simple wire through the frame is required. As mentioned above, SMARTGLASS is initially available in a range of roof lanterns. Five size options are available:


Further information can be requested from Evander – one of the leading property services companies in the UK.