Sunday, 20 June 2010

Steel Windows Then and Now

Ask most people in the United Kingdom about steel windows, and they will talk about the ubiquitous, mass-produced standard metal window.

A much smaller number will mention the use of the Universal Casement in the inspirational designs created by the world’s foremost architects.
Steel windows were used by Frank Lloyd Wright at Fallingwater, regarded by many as his masterpiece.
Louis Cordonnier’s Peace Palace in The Hague
Albert Kahn’s General Motors Building, Detroit

Even fewer will talk of the architectural movements which were made possible because of the essential characteristics of steel windows.
Inspired by Frank Lloyd Wright, Walter Gropius founded the Bauhaus (House of Building), one of the most influential architecture and design schools of the 20th century.
The Hoover Building a Showpiece Art Deco Design in Perivale, Middlesex

My love affair with steel windows, and, with that, a dislike of inappropriate refurbishment, started very early in life. I was brought up in a row of imposing, large, Victorian semi detached houses, in a North Western town.

At the end of the row, the local coal merchant had built himself an art deco villa, with flat roof, white rendered walls, and sweeping curved corners.
A Typical Art Deco Villa

Eventually I went away to university, and started working in London. Then, on a visit home, I was horrified to find that it had been split into two houses, and the new owners had modernized it. One half of the flat roof was now pitched, the render on the other half had been replaced by pebbledash, and, worst of all, the curved steel windows had been replaced by facetted plastic.  

What do you think?

Side view Courtesy Google Street View

So, how did a blacksmith’s shop in a small market town in North Essex become the world leader in window manufacture, with manufacturing plants on five continents?

Metal windows had been used since Tudor times. The Elizabethan casement glazed with leaded lights was an architectural feature unique to Britain. Glass was so expensive in Britain that people took great care to ensure that the frames were strong. They were very popular as nearly every village had a skilled blacksmith who could manufacture them, but very few had skilled joiners to provide an alternative in timber.

Elizabethan Casement

With the advent of Palladio and Wren’s architectural styles, coupled with improvements in the glass manufacturing process, the fashion for larger, more dignified house building, with corresponding larger windows, grew. The double-hung wooden sash window became the window of choice for the discerning homeowner.

The Courts, Holt, Wiltshire
However, there was some dissatisfaction with timber sash windows. Complaints ranged from broken sash cords, warped sashes, and sticking, shrinking or rattling.

Crittall’s had been manufacturing metal windows for agricultural buildings, and churches using wrought iron, bronze, and increasingly with mild steel. With the attitude that epitomizes the spirit of the Victorian age, Francis Henry Crittall, with his team of skilled craftsmen, set out to develop an engineered window, made of metal, which would overcome all of the problems of the wooden sash.

At the same time, a number of companies around the country were manufacturing metal windows. Wragge’s of Manchester were the pioneers; they were soon joined by Wenham & Walters, Williams & Williams, Hopes, and Burt & Potts.

Improvements in machine tools allowed the first change made to the design, which was the introduction of rudimentary dovetail joints for corners rather than brazing, which resulted in a considerably stronger and more reliable product than before.

Despite the improvements in the steel windows, they were not readily accepted in the residential market. However, in other sectors, the new windows were extremely popular. Projects included the National Gallery, Harrow School, the Royal College of Music, and the Public Records Office.

The next major development in the design of steel windows was the fenestra joint, which, because of its strength, allowed slimmer glazing bars, and therefore more daylight through the windows.

In 1909 following rationalisation work carried out by Walter “Pink” Crittall, the Universal Ranges of steel sections were launched which allowed improvements in the manufacturing process, with the result that consistent manufacture of steel windows could be achieved by semi-skilled workers, rather than skilled craftsmen as previously.

Cover of the 1911 Crittall Catalogue

Further innovations followed, including the welding of corners, hydraulic straightening of bars, and a dual strike plate for handles to allow night-time ventilation with no loss of security.

This all resulted in a better performing window, at a lower cost. However, the Universal Casement was still a luxury product at a premium price.

The First World War proved to be a turning point for the steel windows industry as a whole. Factories were turned over to the manufacture of munitions, and many lessons were learnt which would be adopted in the immediate post war era.

At the time, steel windows were still more expensive than their timber counterparts.

This was about to change.

Productivity improvements that could be gained as a result of standardisation, was the first lesson put into practice. Crittall’s closest rivals, Henry Hope, proposed the adoption of a standard design, to help the steel window industry compete to supply windows for the 200,000 new homes promised to be built by the UK government in 1919.

A new, light, profile was designed to act as a mullion which would allow composite units to be built. Following long discussions with architects, standard units were designed, which matched the current brick sizes, and suited the height of the modern room.

The first project which used these ‘cottage windows’ was for the Admiralty in Chepstow. A typical window was sold for £1.95 including fittings which was a few pennies cheaper than the equivalent timber window without fittings. Further work was carried out for Bristol Corporation, which had a massive building programme for the post war years. The increased volume saw even further cost reductions.

Crittall Brochure for The Cottage Window

In 1920, following much canvassing by Valentine Crittall (later Lord Braintree), the Ministry of Health, at that time responsible for government housing specifications, agreed to include the standard cottage window in its plans for housing schemes. From then on, it was used in almost every housing scheme throughout Britain up until the 1980s.

The success of the steel window is due, in no small part, to the continuous improvement in product, and manufacturing processes.

Further innovations followed which include the development of a comprehensive range of standard metal windows, zincspra, and subsequently, hot-dipped galvanizing, to protect the steel frames, and the Duralife polyester powder coating to provide an enameled finish to the windows.

Performance improvements have been achieved by modified profiles to incorporate double glazed units, and improved weatherproofing.

Today, the steel window is no longer a high volume product in mass production. As a result, there are cheaper alternatives available. But, you get what you pay for.

Today’s homeowners’ decisions on refurbishment incorporate take into account energy performance and sustainability of the materials used.

The thermal performance of the modern replica steel window has been tested and proven to be 400% more efficient than the original single-glazed window.

Steel is the most recycled material in the world (source:  The mild steel which goes to make today’s steel window frames contains 98% recycled material.

In March this year, a West London homeowner was refused planning permission to replace his Crittall steel windows with aluminium units, on the basis that modern, double-glazed steel windows were readily available. (source: Planning Magazine)

In North America, the steel window is seen much more as an aspirational product, as can be seen by the images and comments at this popular North American interior design blog, appropriately named Things That Inspire The Crittall Windows’ North American residential customer list reads like a Who’s Who of successful businessmen, politicians, and entertainers.

Crittall Windows are so successful in North America that in April this year, it was announced that they had won the coveted Queens Award for Enterprise in International Markets. This British-owned, independent company, the largest supplier of steel windows in Europe, is now the No 2 supplier of steel windows to the North American market having built a distribution network from scratch following a management by out in 2004.

Wednesday, 21 April 2010

Crittall Windows scoops Queen’s Award

The last six years have been hectic for Britain’s oldest manufacturer of steel-framed windows but the outcome has been well worth it. Crittall Windows has been awarded a Queen’s Award for Enterprise in International Trade for successfully attacking overseas markets, particularly in the USA.


“This is in effect an award for excellence in how we have gone about our business.” says Managing Director John Pyatt. Everything is taken into account – employment practices, environmental policy, and our work with the local community – as well as our export achievements.”


These achievements are underlined by a significant increase in export earnings from the notoriously protective US market where Crittall windows is now the second largest steel window company operating, despite not maintaining a permanent office in the States.


Established in Braintree, Essex in 1849 and trading as The Crittall Manufacturing Company from1924 until the mid 1970’s, when it became Crittall Windows Ltd, the Essex-based company has undergone major changes since the year 2000. Crittall Windows underwent a management buy-out in 2004 led by John Pyatt. “We acquired the business from its American owners and the existing US distribution network disappeared overnight,” he says.


“We have had to re-establish a whole distribution network in the US in order to get where we are today. Then, in 2007 we moved to a brand new factory.” This involved shifting the machines, processes and some 200 employees from Braintree to Witham to recently-built industrial premises of which Crittall was the first occupant.


The pre-recession move gave the company a state-of-the-art facility from which to run its operations in both the UK and abroad. “We continue to be the number one steel window company in the UK across a very broad spectrum of markets “says John Pyatt, noting that the recovery in Britain is a very fragile one. By contrast, in the US the economy is beginning to pick up strongly. “Things were quiet there last year but now we are seeing a swift improvement,” he says.


The sort of projects in which Crittall Windows are specified across the pond include high end luxury housing and apartment blocks such as 300 Central Park West in New York. Also in the Big Apple is the prestigious Crosby Street Hotel. Then there are the Ivy League universities of Princeton and Yale. There are, says John Pyatt, several opportunities now in other universities and public sector buildings.


The recovery in the US market and Crittall Windows’ success in tapping into it is demonstrated by a significant increase in export sales in the first few months of this year.


Meanwhile in the UK the firm has remained strong in the heritage market plus the school and university sector through the Building Schools for the Future programme. “Clients and contractors are moving projects around to get best value. They are constantly reviewing technical specifications. Everyone has to win jobs on tighter margins,” he says.


The principal difference between overseas markets and the UK is that in the UK Crittall fulfil the roles of designer, manufacturer, glazier and installer, whilst for overseas contracts Crittall acts as designer and supplies only the frames to the local glazier.


Recent prestige projects in the UK include the University of Sussex, Grade 2 listed Lichfield Court in Richmond upon Thames, and the restored and refurbished Royal Shakespeare Theatre in Stratford-upon-Avon.


The citation for the Queen’s Award for Enterprise in International Trade makes reference to the company’s employment practices, its quality control, its health and safety record and its green credentials. John Pyatt pays tribute to his loyal and hard working employees, one in ten of whom has served the company for more than 40 years.


“We feel proud and honoured to be recognised by the Queen’s Award for our work and success in the overseas market.” he says. “America can be seen as one of the hardest markets to compete in and this accolade is the culmination of Crittall’s long history showing how a professionally-managed private company with an excellent product, a strong brand and an enthusiastic workforce can take on the Americans at their own game.”

Posted via web from John's Posterous

Friday, 26 March 2010

West London Planners Refuse Appeal to Replace Steel Windows With Aluminium

Further to my previous post about Du Cane Court, and the effect that the proposed replacement of the original steel windows with aluminium, I found this article in Planning Magazine.

DC Casebook: Householder Development - Window loss blocked in conservation area

Householder development

Planning, 12 March 2010

The owner of a semi-detached house in west London has been refused permission to replace three Crittall metal windows with aluminium windows on the grounds that it would harm the character and appearance of a conservation area.

The inspector found an interesting mix of architectural styles on the estate, where much of the housing was influenced by the modern movement. A local design guide stated that a curved, streamlined shape, as exemplified by Crittall windows, was a feature of many houses. It identified the loss of traditional fenestration as a key factor in the deterioration of the area's special character.

An article 4 direction restricting permitted development rights reflected the council's strict policy stance on unsympathetic development. The inspector agreed that the proposed replacement windows could not replicate the distinctive curves. The proposal would be contrary to development plan policy requiring schemes to have regard to their historic and architectural context, he ruled.

The appellant complained that curved doubleglazed windows were not readily available. The inspector pointed to the design guide's advice that double glazing could be provided by secondary glazing and that modern double-glazed Crittall windows can be obtained as direct replacements.

DCS Number 100-066-469

Inspector Mike Fox; Written representations

The key phrase for me is "It identified the loss of traditional fenestration as a key factor in the deterioration of the area's special character."

Why is it that one local authority in London can take one view, and a neighbouring one take the complete opposite. Is preservation of our architectural heritage subject to post code lottery now?

Posted via email from John's Posterous

Thursday, 25 March 2010

Is another Art Deco Masterpiece Going To Suffer Inappropriate Refurbishment?

I heard some disturbing news today.

In Balham, South London, stands a grand Art Deco apartment block called Du Cane Court.

Its Wikipedia entry states it is, "A distinctive local landmark, it was opened in 1937 and, with 676 apartments, is the largest privately owned block of flats under one roof in Europe. It is so distinctive (at least from a great height in the air) that it was reputedly used as a navigational landmark by German pilots bombing London during the Second World War"

Further, it claims, "It is widely believed (particularly in Balham) that Du Cane Court was to be the chosen seat of government for Hitler's invasion should his armies successfully conquer the British, though no documentary evidence exists to prove this theory."

There is a proposed refurbishment of this building to include replacement of the original steel windows. Following consultation with local planners, it has been proposed to replace the steel windows with Aluminium, using mock glazing bars instead of true divided lights.

English Heritage state "Window openings and frames establish the character of a building's elevation. They should not generally be altered in their proportions or details, as they are conspicuous elements of the design."

English Heritage state "Window openings and frames establish the character of a building's elevation. They should not generally be altered in their proportions or details, as they are conspicuous elements of the design."

Last year, a similar Art Deco apartment building in Richmond, West London, carried out a similar refurbishment, and decided to replace their original steel windows with modern, double-glazed replicas from the original manufacturers. The project team and residents of Lichfield Court were so happy with the outcome, that they issued a brocure which is available here in PDF format.

To rub salt into the wound, Crittall Windows, suppliers of the original steel windows, have been asked to quote to supply the aluminium replacements. That's a bit like asking Michelangelo how much he'd charge to paint the Sistine Chapel ceiling in white emulsion.

Let's hope it's not too late to stop a totally insensitive refurbishment of part of our architectural heritage.

Posted via email from John's Posterous

Monday, 15 March 2010

Braintree’s Living Landscapes unveils new bench in Town Centre – to celebrate Crittall Manufacturing Company

A unique steel, circular bench which celebrates the role of Crittall’s Windows in the life of Braintree, has been unveiled in the town.


The bench, especially commissioned by Braintree Local Committee’s Living Landscapes Project to surround a newly planted semi-mature London plane tree, was officially unveiled on Friday 12th February by special guest, The Hon Mrs Valentine Richardson - the only surviving daughter of the late Valentine G Crittall, who became Lord Braintree and was a former Chairman of the Crittall Manufacturing Company.


The bench, created by Essex artist Tim Ward, is inspired by the distinctive forms of Crittall windows and incorporates colour plates of images reproduced from the Crittall archive at Braintree Museum.


At the unveiling, Hon Mrs Valentine Richardson said:”I wouldn’t have missed this for anything.  I love the bench - its clean and simple design is really attractive. This has been a really special occasion.”


The new bench and tree planting were made possible thanks to Braintree District Council’s Braintree Local Committee which established the Living Landscapes project to introduce new tree planting and associated benefits into the town. 


Cllr Wendy Schmitt, Chairman of Living LandscapesTree planting and environmental improvements are the things that the local people of Braintree most supported at our public meetings. So this is great news for the town – we know that trees can boost the ‘feel good’ factor of a town, appealing to shoppers, visitors and traders alike.

“Not only do people love to see trees in towns,  they help off-set the effects of climate change too, by creating shady areas for visitors and shoppers, making streets and buildings cooler in summer, cleaning the air we breathe and helping to reduce wind speeds.”

To plant the London plane tree, Stewart Landscape Construction used specialist urban planting techniques including ‘root cells’ which provide an adequate rooting area without impacting on paving and nearby properties


Braintree District Council’s Landscape Services team is managing the Living Landscape project which set aside funds from Local Area Committee and Essex County Council to achieve a number of green initiatives. Work to date has included planting new trees along Pierrefitte Way to create a ‘green gateway’ into the town; traditionally managing woodland at Kings Wood at Marks Farm; improving local green spaces and planting new plane trees in Braintree town centre. Work continues this spring with more tree planting and new seating at Great Square.

Posted via email from John's Posterous

Tuesday, 2 February 2010

How Essex CC build a path through a council estate, and a private estate

Over the last 4 months, Essex County Council have been widening and extending an existing footpath that runs alongside Salary Brook Local Nature Reserve from the Greenstead (“magic”) Roundabout to The Beehive pub on Bromley Road, a distance of about 2 miles.

On Sunday, I walked the length of it with the dogs, and was surprised, and disappointed, to see the different ways that the contractors had treated the land alongside the new path. Here are some pictures:

This is the path as it runs through a green area in Longridge Park, an estate of privately owned houses.

This is the path running behind a council estate, approaching a children’s play area, which is heavily used.

This is the grassed area leading down to the children’s play area.

This is a new section of path, through a previously fenced off, grassed area which was safe for smaller children to play, and was used in Summer for community barbecues.

This is the section of the nature reserve that they used to get from one section of the path they were working on to another.

I know that over time the land will recover, but the question I have to ask is, why treat the path through the private estate with so much more care than through the council estate? The only people I ever see on the green area have been dog walkers, whereas the other areas are well used by the residents.

Posted via email from John's Posterous

Wednesday, 6 January 2010

Steel Windows Cause Condensation Don't They? - No They Don't

This morning, during a conversation on Twitter about Crittall Windows, I was asked, "are they still made of metal? coz metal windows tend to cause condensation."

My reply was to point to the article on condensation on the Crittall website that I had written.

I decided to republish it here, with some updates.

Steel windows have a reputation of creating condensation. However, this is a fallacy. Condensation will appear on any single-glazed window. The paragraphs below explain what creates the conditions for condensation.

Condensation Explained

Condensation occurs where humid air comes into contact with air, or a surface, which is at a lower temperature.

Air contains water vapour. The warmer the air, the greater is its capacity for carrying water vapour. When warm, moist air comes into contact with a cooler surface, or cooler air, it drops in temperature, and loses some of its capacity for storing moisture, so some of it is released to form condensation in the air, as steam, or on the surface, as water droplets.

We usually observe condensation on surfaces that cannot absorb liquid, e.g. windows, ceramic tiles etc, but it can form on any surface, and it may not be noticeable until mould appears, or the material starts to rot.

Where Does The Moisture Come From

Day-to-day human activities generate warm, moist air. An average family can generate as much as 10 litres of moisture without really trying:

    * Breathing,
    * Cooking,
    * Personal Hygiene,
    * Laundry

In winter, the moisture content can be increased because of heating, which can also generate moisture, as well as increase the capacity of the air to carry water vapour.

Moisture can also be drawn from the fabric of the building itself, where faults have developed because of, for example, a failed or missing damp proof course, or damaged drainage systems.

Reducing Condensation

The most effective ways to reduce condensation are:

1. Check and repair the structure of the building,

2. Reduce the moisture content of the air, by:

    * After a bath or shower, open a window to the outside, and close the bathroom door.
    * Where possible, dry washing outside, where not possible, ensure a window is open to provide ventilation to the outside.
    * Add powered ventilation/extraction to areas which generate high levels of moisture e.g. kitchen, bathroom etc.

3. Provide good ventilation, to increase the circulation of air.

4. Replacing old single-glazed windows with modern double or triple glazed-units will reduce the appearance of condensation on the glass. However, the moisture in the air is likely to condense somewhere else, quite often behind furniture, or in cupboards. I have also seen complaints about condensation appearing on the OUTSIDE of A-Rated windows, which is just as unsightly.

It is highly unlikely that a house will ever become condensation-free, but by ensuring the building is maintained in good condition, and by adopting relatively minor changes to lifestyle then it can be reduced.



Posted via web from John's Posterous