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Home Improvement Glossary
The terms guides use, defined in plain English. 15 entries and growing.
B
- Backer Board
- Cement-faced panel installed over studs or subfloors as a tile substrate in wet areas. Provides a stable, water-resistant base that thinset bonds to far better than drywall.
- Board Foot
- Volume unit for lumber: thickness (in) × width (in) × length (ft) ÷ 12. A 1×6 board 8 ft long contains 4 board feet. Hardwood is priced by the board foot.
C
- Coping
- Shaping the end of one piece of trim (typically with a coping saw) to fit the profile of the mating piece — the tight inside-corner joint professionals use instead of mitering.
D
- Dry Fit
- Assembling components without adhesive or fasteners to verify fit before permanent installation. The habit that prevents most irreversible mistakes.
E
- Eave
- The roof edge that overhangs the wall, where gutters mount. Eave length drives gutter, fascia and starter-course quantities.
F
- Flashing
- Metal or membrane installed at roof and wall intersections to direct water away from the structure. Missing or corroded flashing is behind most hidden rot.
G
- GFCI
- Ground-Fault Circuit Interrupter — an outlet or breaker that cuts power in milliseconds when current leaks from the intended path. Required near water sources; test monthly.
J
- Joist
- Horizontal framing member that supports a floor or ceiling, spanning between beams or walls. Spacing (typically 16 in on center) determines floor stiffness.
L
- Load-Bearing Wall
- A wall carrying structural weight from above. Removal or modification requires professional structural design and permits — never a DIY project.
M
- Mortar Joint
- The mortar layer between masonry units, typically 3/8 in (10 mm). Joint thickness is part of every brick and block quantity calculation.
P
- Pitch
- Roof slope expressed as rise per 12 units of run (e.g. 6/12). Pitch multiplies the sloped roof area above the building footprint.
R
- R-Value
- Resistance to heat flow — higher is better. Insulation requirements are specified by R-value; total R-value is additive for stacked layers.
S
- Stud
- Vertical framing member (typically 2×4 or 2×6, spaced 16 or 24 in on center) behind wall surfaces. Fasteners for heavy loads must reach studs or rated anchors.
- Subfloor
- The structural sheathing (OSB or plywood) fastened to floor joists, under the finished floor. Flatness and squeak-freedom here determine finish-floor quality.
V
- Vapor Retarder
- Material (facing on batts, sheet poly, or paint) that slows water-vapor migration through assemblies. Orientation depends on climate — verify local practice before installing.