Crematoria authorities limit each service to 15 or 20 minutes. Should we exceed this, clergy are likely to be ticked off on the spot by an official and receive a letter afterwards. This was my experience when I went one minute over time in order to incorporate hymns and readings requested by the family of a lifelong church member.
Until crematoria start to reform themselves and offer more flexibility I would advise relatives to ask their minister for a service in church followed by a short committal in the crematorium. Freed of the need to keep an eye on the clock, he or she will be in a better position to help the bereaved mourn fittingly and to remind them of their own mortality.
High Street Methodist Church