Water Infiltration Number

WIN is a points-based metric for architecture students to assess the risk of water infiltration in their studio projects and to gain an understanding of the relative importance of major design decisions and the local climate.

Climate Considerations

Annual rainfall

Site And Groundwater Considerations

Does grade slope away from the building?

Is any of the building below grade?

Is any of the below-grade portion of the building also below the water table?

Wall Assembly Considerations

Is it a mass wall (for example structural concrete block or cast in place concrete) or a framed wall (for example steel or wood studs)?

If the wall is framed, does it have a dedicated space (min. 1/8 inch) for drainage behind the cladding?

Roof Considerations

Is the roof pitched so that water drains off the edge of the building, low-slope (“flat”) and pitched to internal drains, or inverted pitched to a central gutter (butterfly roof)?

Does the roof have skylights or dormers?

Architectural Features

Are there balconies?

Is there a terrace, pool deck, or green roof over occupied space?

Terrace (10 Points) Pool deck (10 Points) Green roof (10 Points) None (0 Points)