1. SILL NOSE 1 Sill Nose is installed under a threshold to protect the exterior edge of a foundation or door sill 2 Measure width of opening and cut sill nosing to size 3 Place sill nosing so that it is tight against foundation or sill 4 Fasten to foundation or sill with screws concrete nails or construction adhesive not included 5 Install threshold over sill nosing to complete the project