Make sure you notify the Government if you expect to make more than 20 staff redundant. 

If you need to reduce your staff by more than 20 and less than 100 in a 90 day period, you must inform the Department for Business, Enterprise & Regulatory Reform (BERR) at least 30 days before you intend to make redundancies. 

If you need to reduce your staff by more than 100 in a 90 day period you must give 90 days notice. 

Details can be found on their website www.berr.gov.uk.   

ACAS has published a guide  to Redundancy Handling and a Disciplinary and Grievance Procedures Code of Practice which can be found on their website www.acas.co.uk.