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The Brynmawr Rubber Factory - Semtex

Over the years this area has seen much of its heritage destroyed either by being allowed to fall into an irreparable state, or because of an inability to understand the significance.  One such tragedy was the destruction of Brynmawr’s Rubber – later Semtex - Factory, world- renowned as an outstanding example of modern architecture.  

A post card issued by the Twentieth Century Society in support of a campaign to save the Brynmawr

Rubber Factory, stating how this organisation was “working with local people to save a great building.”    

The above photograph was taken from the road to Winchestown looking north towards Brynmawr.  The person that must be thanked for the factory being built at Brynmawr was Jim Forrester, an Old Etonian and Quaker, who was to become the Earl of Verulam.  He had worked in Brynmawr with the Quakers during the 1930’s Depression and on leaving prior to WW2 promised that he would build a factory of which Brynmawr would be proud.  In the years preceding the Second World War Germany had championed the use of reinforced concert in building, establishing a modernistic approach to architecture.  After the war many young British architects went to Germany to see the progress that had been made in this field and how such structures had survived RAF bombing; the best example of which being the U-Boat pens at Brest.  One of these visitors was Ove Arup, a young and aspiring architect born of Danish parents, who had become interested in reinforced concrete work and who would be given the task of designing the Brynmawr factory.  Between 1946 and 1951, Ove Arup built around him a design team including J. Varing and Parneres, all playing an important role integrating engineering services into an elegant design, creating superb modern architecture that would be listed Grade 2.  Interestingly the factory would provide a common entrance and similar facilities for both management and workers.

The factory complex consisted of eight domes each measuring 25 by 19 metres square, the height from the support walls to the crown being 2.4 metres.  Material used in its concrete construction came from Hereford, none suitable being found in Wales.  When each dome was being cast, it was a constant and on-going procedure until completed; a local man recalling how work started at 6.30 a.m. and would not finish until well after midnight.  

However the market in flooring would be undercut by cheaper imports from abroad and, eventually, the factory had to close, being allowed to fall into a state of ugly despoliation although remaining structurally sound.  When the borough announced its intention to demolish the building, architectural experts from Europe, USA and many other countries, together with those of British Universities strongly supported efforts by local people to preserve this exceptional building but all to no avail.  Even though it was pointed out that this fine structure with its unrestricted covered area could readily be adapted into any number of uses, e.g. sports, shopping or education etc., its destruction had been firmly decided upon.   This was a tragic ending for a building of outstanding architectural design, visited by international students and one that had helped take the UK into a new “Elizabethan Age”.  Only the boiler house now remains of a world-class structure of which Brynmawr and Wales should have been extremely proud.  “Demolishing such a building” said one leading international expert, “would be like knocking down a cathedral!” but his words and those of many others, fell on deaf ears and closed minds.  In its place has arisen a supermarket whose design would seem to contradict a claim made by one in authority that the Rubber Factory’s demolition meant “a carbuncle has been removed from the face of Brynmawr.”

            Norman Griffiths

Photo 07

This is "The Ramp"  or entrance to the Semtex Building originally named Brynmawr Rubber Factory.

All entered the factory by the ramp, managers and workers alike. “He’s been sent down the ramp” meant someone had been sacked or laid off.

Photo 08

During a winter of discontent. Workers occupied Semtex building over a Christmas period as a protest to the firm moving to South Africa.

Brynmawr Boiler House ( On main road south of Town Centre)

Only this dilapidated boiler house remains of the Brynmawr Rubber Factory whose advance concrete-domed structure was studied world-wide. Designed by Ove Arup, as was the Sydney Opera House, the factory was allowed, after closure, to fall into superficial disrepair and then demolished in spite of local and national campaigns urging its re-use  for other purposes. “To destroy this  fine building would be like knocking down a cathedral” said one leading architect  but, even so,  a supermarket now occupies its former site. Only a boiler house remains to recall a time when Brynmawr possessed an important example of world-class modern architecture.

The photo to the right is of famous actors Alan Rickman, Victor Spinetti and  Kevin Whately with Mark Lewis, who was trying to obtain funding to change the Boiler House into a theatre and theatre workshop. Support came from some very famous people.

The  button to the right links to an article in  'Wales Online', marking  the death of actor Alan Rickman in March 2015, and the part that he and other actors played in 1994, in a bid to save the building.

Wales Online

Semtex Factory being demolished

Downloadable PDF Files

The four files below were created  by scanning  booklets/documents about the building of the "Brynmawr Rubber Factory", photos of the factory in production and a document charting the "Rise and Fall" of Semtex, please click on the link buttons to view/download.

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