Fist of all let me ask, are you a true JV, in the legal sense, in that the Client will be contracting with both of you directly?
If not, the answer is that designer will be a Subcontractor and paid for in as Defined Cost in in accordance with that contract under heading 4 of the re-jigged (compared with NEC3) Schedule of Cost Components.
If it is a genuine JV and the designers are not working in the Working Areas, then you are right, they would be paid for a Design 7.
Alternatively - and depending upon the circumstances - what I have seen done is a part of the design office is used exclusively on a specific contract. That part - a room say - is specified as part of the Working Areas.
If not, the answer is that designer will be a Subcontractor and paid for in as Defined Cost in in accordance with that contract under heading 4 of the re-jigged (compared with NEC3) Schedule of Cost Components.
If it is a genuine JV and the designers are not working in the Working Areas, then you are right, they would be paid for a Design 7.
Alternatively - and depending upon the circumstances - what I have seen done is a part of the design office is used exclusively on a specific contract. That part - a room say - is specified as part of the Working Areas.