The proposed policy approach will require continual updating of the self and custom build register(s) to reflect the permissions that have been granted with a self- or custom-build element. Close monitoring on sales and completions will also be necessary in case plots earmarked for self- or custom-build revert to market dwellings at the end of the prescribed 12-month marketing period.

It is also unclear if the current registers for Cambridge City and South Cambridgeshire are to be combined, with delivery of plots across the wider area. This would not be logical since many prospective self-builders will have preferred locations and few will have a search area as wide as Greater Cambridge. A more focused policy, perhaps split across the two administrative areas, would encourage the development of self-build plots in the right locations to meet local demand. For example, if all the need for plots was in and around Cambridge, it would not make sense to burden developers in other parts of the area.