Alabama - Carpentry and Framing Contractor

Nominal dimensions (e.g., 2×4) are the named size used for specifying lumber on drawings and board-foot calculations, while actual/net dimensions (e.g., 1½"×3½") are the true dressed size required for engineering computations.

A quantity takeoff is prepared from completed construction documents using actual counts and measurements, while a pre-design estimate is a rough approximation made before drawings are finished, often using historical cost-per-unit data.

At eaves the underlayment is installed OVER the drip edge, while at rake edges the drip edge is installed OVER the underlayment.

A plan view looks straight down from above (used for floor plans, roof framing layouts, and site plans), while a section or elevation view looks horizontally to show heights and vertical relationships.

Joists resting on top of a girder bear directly on it, while joists framing into the side must be supported by approved framing anchors or ledger strips of at least nominal 2×2.

Rafter spans in IRC span tables are measured along the horizontal projection of the rafter, not along the sloped actual rafter length.

A unit-cost estimate divides the building into components measured in lineal feet (walls) or square feet (floors/roofs) and applies a cost per unit, while a board-foot estimate counts individual pieces using nominal dimensions to find total lumber volume.

A theodolite reads both horizontal and vertical angles electronically with an LCD display for high-accuracy work, while a builder's level establishes elevations and horizontal sightings but does not electronically display angle measurements.

Differential leveling is used when points are remote from each other and require one or more intermediate instrument setups, while single-setup leveling determines elevation differences from one instrument position.

A window/door schedule is a chart providing rough-opening sizes and window/door designations, while a room-finish schedule identifies the floor, wall, and ceiling materials and finishes for each room.

When ceiling joists or rafter ties are located at one-third the ridge height above the support walls, a factor of 0.67 must be applied to reduce the tabulated rafter span, reflecting the increased outward thrust on bearing walls.

Batter boards are temporary wood structures set at least 4 feet beyond each foundation corner to hold layout strings, while a reference line is an existing feature (street, property line) from which measurements are taken without a surveying instrument.