silllength

Silllength is a term used to describe the horizontal extent of a sill, most commonly in two related fields: architecture and geology. In architectural usage, silllength refers to the length of a window or door sill measured along the sill’s front surface from one end to the other. It can influence how a window or door is framed, how water drains away from the building, and how exterior trim, flashing, and sill pans are installed. Silllength typically corresponds to the width of the opening but may be extended by exterior overhangs, trim projects, or integrated sill extensions. For interior finish work, accurate silllength is important to ensure a proper fit for window frames, casings, and any decorative elements.

In geology, silllength describes the horizontal reach of a sill intrusion, a tabular sheet of igneous rock that was injected parallel to surrounding layers. Here, silllength denotes the long dimension of the sill along its strike or along the plane of emplacement. It is a key parameter in geological mapping and cross-sectional reconstructions, used alongside thickness (the vertical dimension) to characterize the scale and geometry of the intrusion. Silllength in this sense can range from meters to kilometers, influenced by magma supply and the structural fabric of the host rock.

Measurement conventions vary by field: architecture typically measures along the sill face from inner frame to outer edge, including any projections; geology measures along the sill’s long axis from one inferred endpoint to the other, using field contacts, cores, or geophysical data. See also window sill, sill pan, sill (architecture), sill (geology).