Construction Glossary: Essential Terms for Owner-Builders

Understanding construction terminology is critical for communicating with subcontractors, reading building codes, and navigating the permit process. This comprehensive glossary covers the most important terms you'll encounter as an owner-builder.

A

ABS (Acrylonitrile Butadiene Styrene) - Black plastic pipe commonly used for drain-waste-vent (DWV) systems. Being replaced by PVC in many jurisdictions.

Actual Dimensions - The true size of lumber after planing and drying. A 2x4 actually measures 1.5" x 3.5". Compare to nominal dimensions.

AFCI (Arc Fault Circuit Interrupter) - Electrical device that detects dangerous arcing conditions and shuts off power. Required in bedrooms and most living areas by modern codes.

Aggregate - Sand, gravel, or crushed stone mixed with cement and water to make concrete. Size and quality affect concrete strength.

Air Barrier - Material layer that prevents air leakage through walls, improving energy efficiency. Often house wrap or specialized membranes.

Ampacity - Maximum current-carrying capacity of an electrical conductor, measured in amperes. Determines what size wire to use for each circuit.

Anchor Bolt - Steel bolt embedded in concrete foundation to secure sill plate and structure. Typically 1/2" diameter, 10" long, spaced 6' apart.

Apron - Decorative trim piece beneath a window sill on interior walls.

Ashlar - Pattern of masonry using rectangular stones of varying sizes laid in horizontal courses.

As-Built Drawings - Final set of construction plans showing all changes made during construction. Essential for future renovations.

Attic Ventilation - System of intake and exhaust vents that prevent moisture buildup and reduce cooling costs. Typically 1 square foot of vent per 150 square feet of attic.

B

Backfill - Soil or gravel placed against foundation walls after construction. Should be properly compacted in layers.

Backsplash - Protective wall surface behind sinks and counters, typically tile or stone.

Balloon Framing - Older framing method where wall studs run continuously from foundation to roof. Rarely used today; see platform framing.

Baluster - Vertical posts supporting a stair or deck railing. Spacing must prevent 4" sphere from passing through.

Barge Board - Decorative board covering roof rafters on a gable end. Also called verge board.

Batten - Narrow wood strip covering joints between wider boards in board-and-batten siding.

Batter Board - Temporary wooden frame used to mark building corners and maintain square during foundation layout.

Bay Window - Window that projects outward from wall, creating interior space. Requires special framing support.

Beam - Horizontal structural member supporting joists, rafters, or other loads. May be wood, steel, or engineered lumber.

Bearing Wall - Wall that supports structural loads from above. Cannot be removed without adding support beam.

Benchmark - Reference point of known elevation used for establishing site grades and foundation heights.

Bird's Mouth - Triangular notch cut in rafter where it sits on wall's top plate.

Blocking - Short pieces of lumber installed between joists or studs to provide backing, prevent twisting, or provide fire stops.

Blown Insulation - Loose fiberglass or cellulose insulation installed by blowing into attics or wall cavities.

Board Foot - Volume measurement for lumber: 1" thick x 12" wide x 12" long. Used for pricing rough lumber.

Bond - Pattern of masonry units (bricks or blocks). Common patterns: running bond, stack bond, Flemish bond.

Bond Beam - Horizontal reinforced concrete beam in masonry wall, typically at top of wall.

Bottom Plate - Horizontal framing member at bottom of wall, nailed to subfloor. Compare to top plate.

Box Sill - Platform framing method where joists sit on sill plate with rim joist around perimeter.

Bracing - Diagonal structural members preventing walls or frames from racking. Required by code in wind/seismic areas.

Brick Veneer - Single layer of brick applied to exterior of frame wall for appearance. Not structural.

Bridging - Diagonal or solid blocking between joists to distribute loads and prevent twisting.

BTU (British Thermal Unit) - Measure of heat energy. Used to rate heating/cooling equipment capacity.

Building Envelope - The physical separator between conditioned interior space and exterior. Includes walls, roof, foundation.

Building Paper - Asphalt-saturated felt paper used as moisture barrier. Being replaced by synthetic house wraps.

Bullnose - Rounded edge on drywall corner, stair tread, or countertop.

Butted Joint - Joint where two members meet end-to-end without overlapping.

C

Cant Strip - Beveled wood strip where roof meets wall, smoothing transition for roofing material.

Cantilever - Structural member extending beyond its support, like overhanging floor joists.

Casing - Decorative molding around door or window opening.

Caulk - Flexible sealant filling gaps to prevent air and water infiltration.

Cavity Wall - Masonry wall with air space between inner and outer layers, improving insulation.

Certificate of Occupancy (CO) - Official document stating building meets code and can be occupied. Required before moving in.

Chair - Small plastic or metal support holding rebar at proper height in concrete formwork.

Chase - Vertical shaft containing ducts, pipes, or wires. Must maintain fire rating of surrounding walls.

Circuit - Complete electrical path from panel through devices and back to panel.

Circuit Breaker - Safety device that opens circuit when overloaded or short-circuited. Resettable unlike fuses.

Cladding - Exterior covering of building: siding, brick, stucco, etc.

Clerestory - Window section above normal window height, typically at second story or above roofline.

Cleat - Strip of wood or metal fastened to surface to support another member.

CMU (Concrete Masonry Unit) - Standard concrete block, typically 8"x8"x16" nominal dimensions.

Collar Tie - Horizontal member connecting opposite rafters, typically in upper third of attic space.

Column - Vertical structural member supporting beams or roof loads.

Conditioned Space - Interior area that is heated and cooled. Affects insulation and vapor barrier requirements.

Conduit - Pipe or tube protecting electrical wiring. May be metal (EMT, rigid) or plastic (PVC, ENT).

Construction Documents - Complete set of drawings and specifications for building permit and construction.

Continuous Load - Electrical load expected to operate for 3+ hours, like lighting. Circuits must be sized at 125% of load.

Corbel - Decorative bracket projecting from wall to support shelf, mantle, or beam.

Corner Bead - Metal or plastic strip protecting outside drywall corners.

Cornice - Decorative assembly where roof overhangs wall, including fascia, soffit, and moldings.

Counterflashing - Upper piece of two-part flashing system, typically installed in masonry joints.

Course - Single horizontal layer of bricks, blocks, shingles, or siding.

Crawl Space - Shallow unfinished space between ground and first floor. Must be properly ventilated or sealed/conditioned.

Cricket - Small peaked saddle behind chimney or wall that diverts water. Also called saddle.

Cripple Stud - Short vertical framing member above header or below sill in wall framing.

Crown - Slight bow along length of lumber. Should be installed "crown up" in floor joists.

Curtain Wall - Non-structural exterior wall, typically glass and metal, hanging from building structure.

D

Damper - Adjustable plate in duct or flue controlling airflow.

Datum Point - Fixed reference point for measuring elevations on site. See benchmark.

Dead Load - Permanent static weight: structure, finishes, fixed equipment. Compare to live load.

Deadman - Buried anchor for retaining wall or guy wire.

Deck - Exterior floor platform, typically wood or composite material.

Deflection - Degree to which structural member bends under load. Code limits deflection to prevent damage.

Dew Point - Temperature at which water vapor condenses. Critical for vapor barrier placement.

Diaphragm - Structural element (floor or roof) that distributes lateral loads to shear walls.

Dimension Lumber - Framing lumber 2" to 4" thick and 2" to 16" wide (nominal dimensions).

Double-Hung Window - Window with two vertically sliding sashes, both operable.

Downspout - Vertical pipe carrying water from gutter to ground or drainage system.

Draft Stop - Material blocking concealed air passages to prevent fire spread. See fire blocking.

Drain Tile - Perforated pipe around foundation footer collecting and diverting groundwater.

Drip Cap - Molding placed above door or window to direct water away from opening.

Drip Edge - Metal strip at roof edge preventing water from running under shingles.

Drywall - Gypsum board interior wall and ceiling finish. Also called gypsum board, wallboard, or sheetrock.

Dry Well - Underground pit of gravel collecting roof runoff and allowing it to percolate into soil.

DWV (Drain-Waste-Vent) - Plumbing system carrying sewage and venting sewer gases outdoors.

E

Eave - Lower edge of roof overhanging wall.

Efflorescence - White crystalline deposit on masonry caused by water dissolving salts and evaporating.

Egress - Exit path from building. Bedrooms require egress window meeting size and height requirements.

Elbow - Plumbing or electrical fitting changing direction of pipe or conduit.

Elevation - Vertical height above reference point; or exterior drawing of building showing vertical face.

EMT (Electrical Metallic Tubing) - Thin-walled metal conduit for protecting electrical wires.

Energy Heel - Raised heel on roof truss allowing full-depth insulation at exterior wall. Also called raised-heel truss.

Engineered Lumber - Manufactured wood products: LVL, I-joists, glulam, etc. Stronger and more consistent than dimensional lumber.

Escutcheon - Decorative plate covering hole where pipe penetrates wall or floor.

Expansion Joint - Intentional gap in concrete or masonry allowing for thermal expansion/contraction.

F

Fascia - Vertical board at roof edge, typically where gutters attach.

Feeder - Electrical circuit supplying power to subpanel or large equipment.

Fenestration - Arrangement and design of windows in building.

Fill Sand - Clean sand used for backfilling or as leveling bed under slabs.

Finger Joint - Method of joining wood pieces end-to-end using interlocking "fingers" and adhesive.

Fire Blocking - Materials installed to prevent vertical air movement in walls that could spread fire.

Fire Rating - Time (in hours) material or assembly can withstand fire exposure. Required for certain walls and floors.

Firestop - Material preventing fire and smoke spread through penetrations in fire-rated assemblies.

Flashing - Thin metal or membrane preventing water intrusion at joints: roof valleys, chimneys, windows, doors.

Floating Floor - Floor finish not attached to subfloor, allowing for expansion/contraction. Common with laminate and engineered wood.

Floor Joist - Horizontal framing members supporting floor loads.

Flue - Passage in chimney conducting smoke and gases to atmosphere.

Fly Rafter - Rafter at gable end extending beyond supporting wall to form overhang.

Footing - Concrete base spreading load from foundation to soil. Sized based on soil bearing capacity.

Form - Temporary structure holding concrete in desired shape until it cures.

Foundation - Below-grade structural element supporting building. Types: slab, crawl space, basement.

Framing Plan - Construction drawing showing size and location of structural framing members.

Frost Line - Depth to which ground freezes. Footings must extend below frost line to prevent heaving.

Furring - Thin wood or metal strips attached to wall or ceiling to provide level surface or airspace.

G

Gable - Triangular section of wall at end of pitched roof.

Galvanized - Steel coated with zinc for corrosion protection. Common for nails, pipes, flashing.

Gambrel Roof - Roof with two slopes on each side, lower slope steeper than upper. Common on barns.

Gang - Multiple electrical boxes mounted together, like double or triple switch box.

General Contractor (GC) - Person coordinating all aspects of construction. As owner-builder, you perform this role.

GFCI (Ground Fault Circuit Interrupter) - Safety device detecting current imbalance and shutting off power. Required near water: bathrooms, kitchens, exterior.

Girder - Large horizontal beam supporting joists. May support entire floor section.

Glazing - Glass in windows and doors; or the process of installing glass.

Glulam (Glue-Laminated Timber) - Engineered lumber made from layers of dimensional lumber glued together. Used for beams and headers.

Grade - Ground level around building; or quality rating of lumber.

Grade Beam - Reinforced concrete beam at ground level, typically connecting piers.

Grading Plan - Drawing showing existing and final ground elevations around building.

Green Lumber - Freshly cut lumber with high moisture content. Should be avoided for framing.

Grout - Thin mortar filling joints between tiles; or concrete filling CMU cells.

Gusset - Plywood or metal plate connecting and strengthening truss or frame joints.

Gutter - Horizontal trough at roof edge collecting rainwater.

Gypsum Board - See drywall.

H

Hanger - Metal bracket supporting joist, beam, or other member. Examples: joist hanger, beam hanger.

Header - Horizontal structural member spanning opening (door, window) and supporting load above.

Hip - Exterior angle where two roof slopes meet.

Hip Roof - Roof with slopes on all four sides meeting at roof peak.

Hold-Down - Metal bracket anchoring wall to foundation, resisting uplift in high-wind or seismic areas.

House Wrap - Synthetic fabric wrapped around exterior sheathing as air and moisture barrier. Brand example: Tyvek.

HVAC - Heating, Ventilation, and Air Conditioning system.

I

I-Joist - Engineered floor joist shaped like steel I-beam, with OSB web and lumber flanges. Stronger and more consistent than dimensional lumber.

Impact Fee - Fee charged by municipality for infrastructure impact of new construction.

Insulated Concrete Form (ICF) - Foam forms remaining in place as insulation after concrete pour. Creates highly-insulated walls.

Isolation Joint - Separation between concrete slabs or between slab and structure allowing independent movement.

IRC (International Residential Code) - Model building code adopted by most US jurisdictions for one- and two-family dwellings.

J

J-Channel - Vinyl siding accessory trim shaped like "J" used around windows and at corners.

Jack Rafter - Shortened rafter running from wall plate to hip rafter or from valley rafter to ridge.

Jack Stud - Vertical framing member supporting header at side of door or window opening. Also called trimmer stud.

Jamb - Side and top members forming door or window frame.

Joist - Horizontal framing member supporting floors or ceilings. Typically spaced 12", 16", or 24" on center.

Joist Hanger - Metal bracket supporting end of joist where it meets beam or header.

K

Keyway - Groove formed in concrete footing to lock foundation wall in place.

Kiln-Dried - Lumber dried in kiln to reduce moisture content, typically to 19% or less. More stable than air-dried lumber.

King Stud - Full-length vertical framing member beside door or window opening, running from bottom plate to top plate.

Knee Wall - Short wall under sloped ceiling in attic space, typically 3-4 feet tall.

Knockout - Removable disk in electrical panel or junction box for bringing in conduit or cable.

L

Lag Bolt - Large wood screw with hex head, also called lag screw. Used for heavy connections.

Laminate - Material made of thin layers bonded together; often refers to plastic laminate countertops or laminate flooring.

Landing - Platform in stairway where direction changes, or at top/bottom of stairs.

Lap Siding - Horizontal siding where upper pieces overlap lower pieces. Also called clapboard.

Lateral Load - Horizontal force from wind or earthquake. Resisted by shear walls and diaphragms.

Lath - Thin strips of wood or metal providing base for plaster application.

Ledger - Horizontal board attached to wall or beam supporting joists.

Let-In Brace - Diagonal brace notched into wall studs to prevent racking.

Lien - Legal claim against property for unpaid materials or labor. See mechanic's lien.

Lien Waiver - Document releasing lien rights upon payment. Critical for owner-builders to collect from all subcontractors and suppliers.

Lineal Foot - One foot of length, regardless of width. Used for pricing molding, base, etc.

Lintel - Horizontal support above opening, similar to header. Often refers to masonry or steel.

Live Load - Variable weight from occupants, furniture, snow, etc. Compare to dead load.

Load-Bearing Wall - See bearing wall.

Lookout - Horizontal framing member supporting roof overhang at gable end.

Lot Line - Legal boundary of property. Setbacks measured from lot lines.

Louver - Slatted opening allowing ventilation while blocking rain and light.

Low-E (Low Emissivity) - Window coating reflecting infrared light, reducing heat transfer.

LVL (Laminated Veneer Lumber) - Engineered lumber made from thin wood veneers glued together. Used for beams, headers, and rim joists.

M

Main Panel - Primary electrical distribution panel containing main breaker and branch circuit breakers.

Mansard Roof - Roof with two slopes on all four sides, lower slope nearly vertical. French architectural style.

Mastic - Thick adhesive for setting tile or adhering materials.

MDF (Medium-Density Fiberboard) - Engineered wood product made from wood fibers and resin. Common for painted trim and cabinets.

Mechanic's Lien - Legal claim by contractor or supplier against property for unpaid work. Owner-builders must carefully manage lien waivers to prevent.

Millwork - Finished wood products: doors, windows, trim, stairs, cabinets. Typically manufactured in mill.

Miter - Angled cut, typically 45°, where two pieces join at corner.

Moisture Barrier - Material preventing water vapor transmission. See vapor barrier.

Molding - Decorative trim with shaped profile: crown, base, casing, etc.

Monolithic Slab - Concrete slab and footing poured in single operation.

Mortar - Mixture of cement, lime, sand, and water bonding masonry units.

Mudsill - See sill plate.

Mullion - Vertical member separating and supporting window or door units.

Muntin - Thin bar dividing glass panes within window sash. Modern windows often have false muntins.

N

Nailer - Blocking installed to provide nailing surface, like for drywall or cabinets.

Nail Pop - Drywall nail or screw pushing through finished surface, usually from lumber shrinkage.

National Electrical Code (NEC) - Standard for electrical installations, adopted by most jurisdictions.

Newel - Large post at top, bottom, or turn of stairway supporting handrail.

Nominal Dimensions - Named size of lumber before planing. A "2x4" is nominally 2"x4" but actually 1.5"x3.5". See actual dimensions.

Non-Bearing Wall - Partition wall supporting no structural load. Can be removed without structural concerns.

Nosing - Rounded edge of stair tread projecting beyond riser.

O

O.C. (On Center) - Measurement from center of one framing member to center of next. Standard spacings: 12", 16", 24".

Oriented Strand Board (OSB) - Engineered wood panels made from compressed wood strands. Common for sheathing and subflooring.

Outrigger - Extension of rafter or joist beyond wall to support overhang.

Owner-Builder - Property owner serving as their own general contractor. You.

Owner-Builder Permit - Special permit for property owners acting as their own contractor. Requirements vary by jurisdiction.

P

Panel - Electrical distribution box containing circuit breakers. Also, large sheet material like plywood or drywall.

Parapet - Low wall extending above roof line.

Parging - Thin coat of mortar applied to foundation or chimney for waterproofing or appearance.

Partition - Interior wall dividing space. May be bearing or non-bearing.

Penny (d) - Nail sizing system. 16d (16-penny) nail is 3.5" long. Originated from price per 100 nails.

Perimeter Foundation - Foundation walls around building perimeter supporting exterior walls.

Perm - Measure of water vapor transmission through material. Low-perm = vapor barrier; high-perm = vapor permeable.

PEX (Cross-Linked Polyethylene) - Flexible plastic pipe for water supply. Easier to install than copper, resistant to freezing.

Pier - Isolated concrete column supporting concentrated load. Common for decks and posts.

Pilaster - Thickened vertical section of masonry wall, providing lateral support or carrying concentrated load.

Pitch - Slope of roof expressed as rise over run. 6:12 pitch rises 6" per 12" of horizontal distance.

Plan Check - Building department review of construction plans for code compliance.

Plank - Thick lumber, typically 2" to 4" thick and 6" or wider.

Plate - Horizontal framing member. Bottom plate at floor; top plate at ceiling; sole plate synonymous with bottom plate.

Platform Framing - Modern framing method where each story built as separate platform. Compare to balloon framing.

Plenum - Space used for air circulation, like cavity above suspended ceiling or below raised floor.

Plumb - Exactly vertical. Checked with level or plumb bob.

Plumb Bob - Weight on string establishing vertical line.

Ply - Single layer in plywood or built-up material. 1/2" plywood is typically 5-ply.

Plywood - Engineered wood panels made from thin wood layers (plies) glued with grain alternating directions.

Pointing - Finishing mortar joints in masonry; or repairing deteriorated mortar joints.

Post - Vertical structural member, typically larger than stud. Supports beams.

Post-and-Beam - Framing system using larger, widely-spaced posts and beams rather than stud walls.

Pressure-Treated (PT) - Lumber treated with preservative forced deep into wood under pressure. Required for ground contact or weather exposure.

PSF (Pounds per Square Foot) - Unit for measuring distributed loads, like floor live loads or snow loads.

PSI (Pounds per Square Inch) - Unit for measuring pressure or material strength. Concrete specified by compressive PSI.

Punch List - List of incomplete or defective items to be corrected before final payment.

Purlin - Horizontal roof framing member perpendicular to rafters, providing intermediate support.

PVC (Polyvinyl Chloride) - White plastic pipe used for cold water supply and DWV systems.

Q

Quarry Tile - Unglazed ceramic tile, typically for floors.

Quarter Round - Small molding with quarter-circle profile, used to cover gap between floor and baseboard.

Queen Post - Vertical member in truss, typically in pairs between peak and lower cord.

Quoin - Decorative corner treatment using contrasting material or larger masonry units.

R

R-Value - Measure of insulation's resistance to heat flow. Higher R-value = better insulation.

Rabbet - L-shaped groove cut along edge of lumber.

Racking - Lateral distortion of wall or frame under load. Prevented by bracing or sheathing.

Radiant Barrier - Reflective material in attic reducing radiant heat transfer. Common in hot climates.

Rafter - Sloped roof framing member running from ridge to wall plate.

Rafter Tail - Portion of rafter extending beyond exterior wall forming eave overhang.

Rail - Horizontal member in door, window sash, railing, or fence panel.

Rake - Sloped edge of gable roof.

Receptacle - Electrical outlet for plugging in devices. Not technically called an "outlet" in electrical code.

Rebar (Reinforcing Bar) - Steel bar embedded in concrete for tensile strength. Specified by number indicating diameter in eighths of inch (#4 = 4/8" = 1/2" diameter).

Retaining Wall - Wall holding back earth at grade change.

Retainage - Portion of payment withheld until project completion, typically 5-10%.

Return - Finish trim returning around corner to wall, like at end of window sill.

Reveal - Portion of surface left exposed, like narrow edge of door jamb visible beyond casing.

Ridge - Horizontal line at top of roof where slopes meet.

Ridge Board - Horizontal board at roof peak where rafters meet. Not structural in conventional framing.

Ridge Vent - Continuous vent along roof ridge allowing hot air to escape attic.

Rim Joist - Vertical board at perimeter of floor framing, closing off joist bays. Also called band joist.

Rise - Vertical height of stairs, roof, or other sloped element.

Riser - Vertical board between stair treads. Maximum 7-3/4" in residential construction.

Romex - Brand name for non-metallic sheathed cable (NM cable), commonly used for residential wiring.

Roof Truss - Engineered roof framing component, typically pre-fabricated, replacing rafters and ceiling joists.

Rough Opening (RO) - Framed opening for door or window before installation. Typically 1" larger than unit size.

Rough-In - Installation of mechanical/electrical/plumbing systems before walls are closed, while framing is still exposed.

Rough Sawn - Lumber surface as it comes from saw, not planed smooth. Used for rustic appearance.

Run - Horizontal distance of stairs, roof, or drain pipe slope.

S

Saddle - See cricket. Also, threshold at exterior door.

Sash - Movable part of window holding glass.

Scab - Short piece of lumber fastened alongside another for reinforcement.

Scarf Joint - Angled joint connecting two pieces end-to-end.

Schedule - List or table on plans showing repeated items like doors, windows, or finishes.

Scratch Coat - First layer of stucco or plaster, scored to provide key for subsequent coats.

Screed - Tool or process for leveling concrete; or strip establishing level for concrete.

Scribing - Marking material to fit irregular surface, like cabinet to uneven wall.

Seismic - Related to earthquakes. Seismic zones have special structural requirements.

Self-Closing - Door or gate required by code to close automatically, like at pool or garage.

Service - Electrical utility connection to building.

Service Panel - See main panel.

Setback - Required distance between building and property line, established by zoning.

Settlement - Downward movement of building or foundation due to soil compression or consolidation.

Shear Wall - Wall designed to resist lateral (horizontal) loads from wind or earthquakes. Requires special sheathing and nailing.

Sheathing - Structural panels covering exterior wall or roof framing: OSB, plywood, foam board.

Shed Roof - Roof with single slope, like half of gable roof.

Shim - Thin wedge of wood or plastic used to level or plumb during installation.

Shoe - See bottom plate.

Siding - Exterior wall covering: wood, vinyl, fiber-cement, metal, etc.

Sill - Horizontal bottom member of door or window opening. Also, see sill plate.

Sill Plate - Horizontal lumber member bolted to top of foundation, supporting wall framing. Also called mudsill.

Sill Sealer - Foam gasket between foundation and sill plate reducing air infiltration.

Single-Ply Roofing - Rubber or synthetic membrane roofing applied in single layer. Common for flat roofs: TPO, EPDM, PVC.

Skylight - Window installed in roof.

Slab - Concrete floor poured directly on grade.

Slab-on-Grade - Foundation type where concrete floor slab poured at ground level serves as foundation and floor.

Sleeper - Wood strip laid on concrete as nailer for finish floor.

Slope - Angle of roof, drain pipe, or grade. Roof slope often expressed as pitch.

Soffit - Underside of eave overhang; or boxed-in area above cabinets.

Soil Stack - Vertical DWV pipe carrying toilet waste.

Sole Plate - See bottom plate.

Span - Horizontal distance between structural supports.

Span Table - Reference showing maximum allowable spans for joists, rafters, beams based on size, species, spacing, and load.

Spalling - Flaking or breaking of concrete or masonry surface, often from freeze-thaw cycles.

Specifications (Specs) - Written detailed description of materials, equipment, and workmanship requirements. Accompanies drawings.

Square - 100 square feet of surface area. Roofing and siding often sold by square. Also, right angle (90°).

Stack - Vertical run of soil or waste pipe.

Stair Carriage - See stringer.

Starter Strip - First course of siding or shingles, often special profile.

Stile - Vertical member in door panel or window sash.

Stirrup - U-shaped rebar in concrete beam resisting shear forces. Also, see joist hanger.

Stop - Molding or edge preventing door or window from opening too far.

Stringer - Diagonal board supporting stair treads and risers. Also called stair carriage.

Structural Engineer - Licensed professional designing structural systems and stamping structural drawings.

Stucco - Cement-based exterior plaster finish applied in multiple coats.

Stud - Vertical framing member in wall, typically 2x4 or 2x6 spaced 16" or 24" o.c.

Subcontractor - Specialty contractor hired to complete specific scope: electrician, plumber, HVAC, etc.

Subfloor - Structural floor surface, typically OSB or plywood, installed on floor joists. Finish floor installed over subfloor.

Subpanel - Secondary electrical panel fed from main panel.

Sump - Pit in basement floor collecting water, with pump to remove it.

T

Tack Strip - Wood strip with protruding tacks securing carpet around room perimeter.

Tape - Process of finishing drywall joints with paper tape and compound. Also, surveyor's measuring tape.

T&G (Tongue and Groove) - Lumber milled with projection on one edge (tongue) fitting into groove on adjacent board.

Tempered Glass - Heat-treated glass that breaks into small pieces rather than sharp shards. Required by code in hazardous locations.

Termite Shield - Metal barrier on top of foundation preventing termite passage. More common in high-termite areas.

Thermal Break - Insulating material separating conductive materials to reduce heat transfer.

Threshold - Bottom piece of exterior door opening, sloped to shed water.

Tie - Metal device connecting structural elements; or horizontal member in concrete form holding sides together.

Toenail - Driving nail at angle to join perpendicular pieces.

Top Plate - Double horizontal framing member at top of wall supporting ceiling joists or roof framing.

TPO (Thermoplastic Polyolefin) - White rubber membrane for flat or low-slope roofing.

Transom - Window above door.

Tread - Horizontal board on stair you step on. Minimum 10" in residential construction.

Trimmer - See jack stud.

Truss - Engineered structural component using triangular web design. Common for roofs and floors.

Turn of Nut - Method of tightening bolts by specific angular rotation rather than torque measurement.

U

U-Factor - Measure of heat transfer through windows. Lower U-factor = better insulation. Inverse of R-value.

UBC (Uniform Building Code) - Older model building code, replaced by International Building Code (IBC).

Underlayment - Layer between structural floor and finish floor, or between roof deck and shingles. Provides smooth surface or waterproofing.

Utility Easement - Legal right for utility company to access portion of property for infrastructure.

V

Valley - Interior angle where two roof slopes meet.

Valley Rafter - Diagonal rafter in valley where two roofs meet.

Vapor Barrier - Material preventing water vapor passage. In cold climates, installed on warm side of insulation. Also called vapor retarder.

Variance - Permission from zoning board to deviate from code requirements due to property hardship.

Veneer - Thin decorative layer over structural substrate. Examples: brick veneer, wood veneer.

Vent - Opening allowing air circulation; or pipe allowing sewer gases to escape above roof.

Vent Stack - Vertical DWV pipe extending through roof, allowing sewer gases to escape and maintaining atmospheric pressure in drains.

Verge Board - See barge board.

W

Wainscoting - Decorative wall covering from floor to waist height, typically wood panels or bead board.

Waiver of Lien - See lien waiver.

Wall Tie - Metal connector linking brick veneer to structural wall.

Waste Pipe - Pipe carrying wastewater (not sewage). Compare to soil pipe.

Waterproofing - Treatment preventing water penetration, typically below-grade applications.

Weatherstripping - Material sealing gaps around doors and windows to prevent air infiltration.

Weep Hole - Small opening in masonry allowing water drainage.

Wet Wall - Wall containing plumbing, typically thicker to accommodate pipes.

Wind Bracing - Diagonal or structural sheathing resisting wind loads.

Window Schedule - Table on plans listing all windows with sizes, types, and specifications.

Wire Mesh - Steel mesh reinforcing concrete slabs. Also called welded wire fabric (WWF) or wire mesh.

WRB (Weather Resistant Barrier) - Layer preventing water infiltration while allowing vapor passage. Common example: house wrap.

Z

Zone - Area served by single heating/cooling thermostat. Also, geographic area with specific building code requirements (seismic zone, climate zone, etc.).

Zoning - Local ordinance regulating land use, setbacks, building height, and property development.

Zoning Variance - See variance.

Owner-Builder Specific Terms

Owner-Builder Permit - Special building permit issued when property owner acts as general contractor. Requirements vary: some jurisdictions require affidavit, testing, or insurance; others treat same as contractor permits.

Owner-Builder Exemption - Exemption from contractor licensing requirements when building your own residence. Typically requires owner intent to occupy, not sell immediately.

Construction-to-Permanent Loan - Single loan converting from construction financing to permanent mortgage after completion. Simplifies financing for owner-builders.

Draw Schedule - Timeline for releasing construction loan funds based on completion milestones. Owner-builders must carefully coordinate draws with subcontractor payments.

Builder's Risk Insurance - Property insurance during construction covering structure, materials, and equipment from theft, vandalism, fire, weather, etc. Critical for owner-builders who may not be covered by subcontractor policies.

Interim Occupancy - Temporary certificate allowing limited use before final certificate of occupancy. Rarely granted for residential construction.

Lien Release Requirements - Documentation owner-builders must collect from all subcontractors and suppliers with each payment, preventing future mechanic's lien claims.

Sweat Equity - Value of owner-builder's labor contributing to project. May count toward down payment for some construction loans.

Self-Help Building - Another term for owner-builder construction, more common historically.

Code and Permitting Terms

AHJ (Authority Having Jurisdiction) - Local building department with authority to enforce codes and issue permits. Your AHJ interprets code for your project.

Code Cycle - Period between updates to building codes, typically 3 years. Projects typically built to code in effect when permit applied for.

Adopted Code - Model code officially adopted by jurisdiction. May include local amendments.

Amendment - Local change to model code. Critical to review your jurisdiction's amendments.

Certificate of Occupancy (CO) - Final permit sign-off allowing occupancy. Issued after final inspection passes.

Temporary Certificate of Occupancy (TCO) - Allows occupancy with minor items incomplete. Time-limited and may have conditions.

Red Tag - Notice from inspector stopping work due to code violation or unsafe condition. Work cannot continue until violation corrected and re-inspected.

As-Builts - Final drawings showing construction as actually built, including any deviations from approved plans. Required in some jurisdictions before CO issued.

Substantial Completion - Point where building is usable for intended purpose even if minor items remain. Affects warranties and insurance.

Final Inspection - Last inspection before certificate of occupancy issued. Verify all required inspections passed and punch list complete before scheduling.

Related Resources

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