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Oasis • Field Helper
Window Sill & Soffit Calculator (Quick J/S Input Helper)
Global Assumptions
Quick rules of thumb (non-binding): default sill ~30 in; egress window head gap is whatever remains; verify locally if bedroom egress limits apply (typical max sill ≤ 44 in). Use this tool to derive missing inputs for energy software when plans don’t call out these dimensions.
Visualizer (selected row)
Wall height (FS) = 96 in
Overhang = 18 in
Click a row to preview. Use Tab to speed through inputs.
Window List
| # | Label / Room | Width (in) | Height (in) | Floor→Soffit (in) | Overhang (in) | Sill Override (in) | Top Gap Override (in) | Sill Elev (AFF in) | Top→Soffit (in) | Header Elev (AFF in) | Notes |
|---|
Assumptions & Notes
- When both Sill Override and Top Gap Override are blank, the calculator uses the Default Sill Target and computes the top gap.
- If you enter a Sill Override, the top gap is computed. If you enter a Top Gap Override, the sill is computed. If you enter both, both are honored and the Header Elevation becomes a check.
- Validation flags: negative gaps, sill > 44 in (egress check), bottom < 18 in (safety glazing check) are highlighted as guidance only.
Oasis • Field Helper
Window Sill & Soffit Calculator (Quick J/S Input Helper)
Assumptions & Notes
- When both Sill Override and Top Gap Override are blank, the calculator uses the Default Sill Target and computes the top gap.
- If you enter a Sill Override, the top gap is computed. If you enter a Top Gap Override, the sill is computed. If you enter both, both are honored and the Header Elevation becomes a check.
- Validation flags: negative gaps, sill > 44 in (egress check), bottom < 18 in (safety glazing check) are highlighted as guidance only.
