Specifications include, but are not limited to: Task 1. Develop Model Scenarios The selected Contractor is tasked with developing a set of building energy model scenarios that are representative of residential new construction in Massachusetts. More specifically the selected Contractor will identify in consultation with the DOER: a) A representative set of common residential building types and their design criteria (e.g. number of bedrooms, square footage, floorplan etc.) similar to, or informed by the rows shown in Table 1. of Appendix 5; and b) A set of baseline and target stretch code scenarios similar to or informed by the columns shown in Table 1. of Appendix 5 Once the set of model scenarios is agreed upon by the DOER and the selected Contractor, the selected Contractor will use existing or modified building examples to add details sufficient to generate a HERS rating and PHIUS/PHI rating for each building type using the appropriate software tools. This set of detailed model scenarios together with an explanatory memo are the anticipated deliverables under Task 1. Task 2. Conduct Building Energy Modelling Analysis The selected Contractor is tasked with building an iterative building energy model analysis for the set of model scenarios defined in Task 1. More specifically the selected Contractor will: a) First conduct the building energy model analysis by calculating the energy use of baseline scenarios agreed to in Task 1 and then proceed to modify the building typologies to achieve target 2021 Stretch Code performance levels agreed to in Task 1; b) Utilize a RESNET-accredited software product for all HERS rating scenario modelling. The selected Contractor shall also provide detailed documentation of all modelling inputs and assumptions and consult with the DOER to review and approve these modelling inputs and assumptions; c) Utilize a Passive house approved software product (e.g. PHPP, WUFI) for all Passive house scenario modelling. The selected Contractor shall also provide detailed documentation of all modelling inputs and assumptions and consult with the DOER to review and approve these modelling inputs and assumptions; and d) Conduct sensitivity analysis for each model scenario to evaluate the impact of different design approaches (such as different envelope and mechanical system designs and fuels) to achieving the target 2021 Stretch Code performance levels. DOER is looking for this analysis to inform cost-effective strategies reflective of the design approaches that residential developers could implement in order to comply with the target 2021 Stretch Code requirements.