Spacia (vacuum) units

An enquiry today on The Windowman Website about these. I chased this one up early last year. After a very long silence, in the summer I received a call from a Pilkington Business Manager apologising for the delay in getting back to me about Spacia units, and we had a long discussion about them. Briefly, they were to be available this spring: The cost was likely to be very high, and sales were likely to be restricted to those conservation projects where there is little alternative and funds are available: They did not expect to sell them in great volume. This was before the economy melted down. He expected the price landed at Tilbury to be in excess of £100/m2. With the depreciation in the currency since then, I would expect, all things being equal, that this would now be closer to £150/m2. That implies a retail price in excess of £300/m2 if the whole project doesn't simply collapse. Presumably, there would be a minimum price for small units, which makes any Georgian window with separate sealed units more expensive than the price/m2 leads you to expect on first sight.
I concluded that they would be no threat to the established double glazing industry for many years to come, on cost grounds alone. I am pleased to report that while my new friend failed to sell me Spacia units, I did sell him a loft-conversion full of Accoya windows. The first time I have turned the tables on a salesman. Very satisfying.
In my view there are better ways of getting a good result without spending a fortune. The pictures alongside show how good a modern timber rising sash can be. My customers love them!