Option cost
The New Rules of Measurement (NRM) are published by the Royal Institute of Chartered Surveyors (RICS). They provide a standard set of measurement rules for estimating, cost planning, procurement and whole-life costing for construction projects.
According to NRM1: Order of cost estimating and cost planning for capital building work, an option cost is:
'...an estimate of the cost of alternative design solutions to achieve the employer’s objectives; so that they can be compared and appraised. Option costs will be incorporated in the overarching cost report.'
NRM1 suggests it may be necessary to estimate the cost of alternative development scenarios for a site as part of RIBA Work Stages A and B or Gateways 1 and 2.
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