This paper, recently published in IBPSA's journal, the Journal of
Building Performance Simulation explores the appropriate spatial
resolution of future weather files for building simulation. It's written
by M. Eames, T. Kershaw & D. Coley.

Building thermal modelling packages require weather data to predict
representative internal conditions. Typically, around the world,
reference weather years of various forms are used which are created from
observations at aparticular location. However, it is unlikely that this
location is identical to that of the building. This can lead toweather
files for coastal locations being applied to inland and upland sites or
vice versa. In the UK, the UKCP09 weather generator has the ability to
produce weather at a 5 km resolution. Currently, it is unclear how
useful this extra spatial resolution will be and it is this question
that is addressed here. It is found that for both future and present
climate, the spatial variability of the weather is the dominating
factor. Although there are geographies where a low spatial resolution
can be used, there are regions where a much higher resolution is
necessary.

The full paper can be accessed for free here:

http://www.tandfonline.com/doi/full/10.1080/19401493.2011.608133