There is currently much excitement being generated about the probability of construction starting on some of the much-talked of copse of towers planned to slice through the skyline of London.

If that prospect smacks of confidence it is in stark contrast to the general prospects for commercial construction in London and elsewhere in the UK, if we accept the latest findings from the surveyors' body RICS.

The future for bread and butter commercial work looks pitiful.

During the final quarter of last year the survey measured the amount of available empty space coming on the market to be rising at its fastest rate in the 10-years since RICS started asking the question. And we can assume the rate to be the fastest since the last property recession in the early 1990s.

With demand falling at a record pace and accelerating (with 71% more surveyors reporting a fall than a rise in occupier demand compared with 53% in Q3 2008), it is inevitable that rents are also falling faster than at any time since the survey started.

This is not a healthy backdrop against which most developers like to build, or to rephrase that against which investors tend to invest, despite oft-spoken ballsy talk of building through the downturn to capitalise on the upturn.

The survey asks about the level of change over the past three months in new development starts and completions across the office, retail and industrial property sectors.

If the tables were on a City trading screen they would be running blood red, with the starts numbers a decidedly bright, bloodier red than those for completions. This suggests that the workload in the pipeline is emptying rapidly.

In normal times with surveys of this type you don't often get a reading of 100% or -100% on a scale measuring the balance between those seeing things going up and those seeing things go down. Change doesn't tend to strike everyone exactly at the same time.

There are a remarkable number of -100s in this survey.

So it would seen that as we see spikes of glass a steelwork reach to the sky in a few spots in London we will be witnessing not just icons to architecture, but icons to hope.

Most everyone else appears to be shutting up shop until the current blizzards of this economic winter have passed.