Issues surrounding property ownership are the cause of many problems and disputes in professional practices. The property that a practice occupies is often owned by the partners, or a group of normally more senior partners often in an SIPP.
Best advice is often that the property should be owned in/by the partnership, in order to take best advantage of the tax reliefs available. Property funding will be a separate consideration that will need to be dealt with.
It is important that there is a clear section in the partnership agreement that deals with how the property is accounted for in the practice. More importantly, it also needs to deal with the issues surrounding partners leaving and joining and how their interest in the property is dealt with. The property can still be held in a group of SIPPS for tax efficiency, but again, care is needed with partners starting and leaving and the rules surrounding transfers to other SIPP members.