Bicycle frames are constructed from materials which place emphasis on being strong, lightweight and stiff to aid power transfer. Aluminium, titanium, steel and carbon are widely used in all levels of frame production.
A Cyclocross Frame is specifically designed to meet the demands of cyclocross riding and racing. It is similar in appearance to a road frame but has been designed with more relaxed geometry and improved mud clearance.
It's essential you choose the correct size frame when buying a Cyclocross Frame. Wiggle’s bike size guide will equip you with the knowledge needed to find the right fit - http://www.wiggle.co.uk/h/option/bikesizeguide
Cyclocross frames are similar in appearance to a road frame, but they have more clearance for mud to pass between the tyre and frame and avoid clogging. Other features are cantilever bosses for Canti's or V-brakes, along with a higher bottom bracket for clearance when riding over obstacles, more upright angles designed for faster handling at lower speeds and the cables usually run along the top tube so they do not get in the way when you have to carry the bike. Cross frames can be built up into commuters or winter hack bikes as they have ample room for mudguards, their upright riding position and fast handling suits city traffic, when compared to a road race bike, they should also be fine for winter club runs.