I realised after a while that this list could be endless so for the moment I just picked what seemed to me the most common and relevant. I hope I'm posting in such a way that you'll be able to work from it.
Architect
Engineer
Quantity Surveyor
Site Clearance/Plant Hire
Foundations
Formwork
Radon Installation/Supply
Timber Frame Erection/Supply
Concrete Floors/Screeds
Roofer
Block/Bricklayers
Carpenter
Plasterer
Plumber (incl. underfloor heating installer)
Electrician
Painter/Decorator
Insulation Supply/Specialist Installation
Kitchen Manufacturer/Installer
Stairs Manufacturer/Installer
Windows/Doors
Tiler
Timber Flooring
Cornices
Guttering
Water-well drilling
Siteworks (incl. drainage, septic tanks, footpaths)
Gardens/Landscaping
Tarmac/Paving
There is obviously potential for expansion, will think of more in time. Hope this is of some use.