It might seem that English metal-window manufacturers are undeservedly castigated as stubborn (AJ letters 31.3.05 and 7.4.05) for the failings of architects to decide and positively instruct how to align glass sight edges in adjoining opening sashes and fixed lights.
Alignment is not correct nor wrong in every or any particular design context, but is a conscious choice to be made - by the designer. That has long been available to, and a responsibility of, architects in selecting and managing component supplies.
There have been and still will be difficulties. My recollection is that in purpose-made 'metal', or more particularly steel windows, design niceties were very well provided for, at least from the 1930s onward, by the 'Universal' hot-rolled steel section large, medium and small ranges, although less readily in the cheaper domestic 'Standard Metal Window' ranges to BS990 and the BS1787 industrial 'Standard Sash'.
However, through decades of shortages following the end of the war in 1945, purpose-made window subcontract quotations were often rushed on preliminary small-scale drawings with skimpy, if any, quality specifications, and orders were won on sharp competitive timing as well as pricing - with price-fixing allegations engaging Parliament's attention around 1960.
Belated design rethinking was unwelcome after an order was landed on vague preliminary details, with tight time and cost allowance for shop drawings and production programming conditioned by material scarcities.
Architects had difficulty in countering discouragement, in the paucity of textbooks and traditional understandings. Joinery workshops were shown proudly to invited visitors, while steelwindow factories and details of available framing and coupling sections seemed jealously guarded secrets.
Recent AJ correspondence suggests secrecy persists, lest architects get too knowledgeable and demanding. As a side issue, domestic steel windows of the 1930s had a reputation for rusting quickly, before neglect of painting was established as the cause and galvanising accepted as essential to assure long life.
John Allan at Lubetkin's Finsbury Health Centre and at 66 Frognal has respected the limits of meddling to 'improve' historic survivors. Making better known the design versatility there and in other newer examples might rekindle a greater market share for English steel windows.
Dan (aka Vivian) Levett, London