Carpentry terms, defined
Plain definitions of the carpentry words that come up on estimates, inspections and supplier calls, written for carpenters. Each term says where it matters on the job and links the Koira calculator, cost guide or template that goes with it.
A
Shared with FlooringAcclimationAcclimation is letting wood flooring or trim sit in the room where it will be installed so it reaches the room's moisture level before it goes down.CarpentryAnchor boltAn anchor bolt is a bolt set in concrete, usually as it is poured, that ties the sill plate or a post base to the foundation.
B
CarpentryBalusterBalusters are the vertical posts between a handrail or guard rail and the stair or floor, filling the open space.CarpentryBaseboardBaseboard is the trim along the bottom of interior walls where they meet the floor.CarpentryBeamA beam is a horizontal structural member that carries loads across a span to posts, columns or walls.CarpentryBoard footA board foot is a unit of lumber volume used to price hardwood and rough lumber, worked out from nominal thickness, width and length.CarpentryButt jointA butt joint is the simplest joint: two pieces meeting end to end or edge to face without any interlocking cut.
C
CarpentryCeiling joistCeiling joists span between walls to carry the ceiling below and often tie the bottoms of the rafters together so the roof cannot push the walls out.CarpentryChamferA chamfer is a flat, angled cut along an edge or corner that takes off the sharp edge.Shared with RoofingCollar tieA collar tie is a horizontal board that connects opposing rafters in the upper part of the roof, near the ridge.Shared with HandymanConstruction adhesiveConstruction adhesive is a heavy glue in a caulk tube used to bond wood, drywall, subfloors, trim and masonry, usually along with fasteners.CarpentryCripple studCripple studs are the short studs above a header or below a window sill that fill in the wall between the opening and the plates.CarpentryCripple wallA cripple wall is a short framed wall between the top of the foundation and the first floor, enclosing a crawl space.CarpentryCrown moldingCrown molding is the angled trim that covers the joint where walls meet the ceiling.
D
F
CarpentryFireblockingFireblocking is lumber, gypsum, mineral wool or approved sealant placed in concealed spaces, such as stud bays and around pipes, to slow fire spreading through them.CarpentryFloor joistFloor joists are the horizontal framing members, set on edge in parallel rows, that hold up a floor.Shared with ConcreteFootingA footing is the wide concrete base at the bottom of a foundation wall, column or post that spreads the load onto the soil.CarpentryFurring stripFurring strips are thin strips of wood or metal fastened to a wall, ceiling or masonry to create a flat, spaced surface for drywall, paneling or siding.
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H
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K
CarpentryKerfThe kerf is the width of the cut a saw blade makes, the material that turns to sawdust.CarpentryKiln-dried lumberKiln-dried lumber has been dried in a heated chamber to a lower, controlled moisture level, so it shrinks and warps less after install.CarpentryKing studA king stud is the full height stud on each side of a door or window opening, nailed to the jack stud and the header.
L
Shared with HandymanLag boltA lag bolt is a heavy screw with a hex head, driven with a wrench or driver into wood to make a strong connection.Shared with PaintingLead-safe work practicesLead-safe work practices are the federal rules and methods for disturbing paint in older homes without spreading lead dust: containment, no dry sanding or open flame removal, and careful cleanup.Shared with DecksLedger boardA ledger board is the board bolted to the side of a house that carries one end of a deck's joists.Shared with FencingLinear footA linear foot is a foot of length along a line, the unit fences, gutters, trim and edging are measured and priced in.Shared with General ContractorLoad-bearing wallA load-bearing wall carries weight from the roof or floors above down to the foundation.CarpentryLVL beamAn LVL is laminated veneer lumber: thin wood veneers glued into a stiff, straight beam used for headers, beams and rim boards.
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P
Shared with ConcretePier and beam foundationA pier and beam foundation holds the house up on concrete piers or posts with beams across them, leaving a crawl space under the floor.CarpentryPlatform framingPlatform framing builds a house one floor at a time: each floor deck is framed and sheathed, then the walls for that story are built standing on it.CarpentryPlywoodPlywood is a panel made of thin wood veneers glued with the grain of each layer crossed, which makes it strong and stable in both directions.Shared with Windows and DoorsPrehung doorA prehung door comes already hung on hinges in its own jamb, ready to set into the rough opening.CarpentryPressure-treated lumberPressure-treated lumber is wood forced full of preservative under pressure so it resists rot and insects, for use outdoors and in contact with concrete or soil.
R
CarpentryRabbet jointA rabbet is a step shaped recess cut along the edge of a board.Shared with RoofingRafterA rafter is one of the sloped framing members that run from the wall plate up to the ridge and carry the roof deck.Shared with RoofingRidge boardA ridge board is the horizontal board at the peak that the tops of the rafters frame against.CarpentryRim joistThe rim joist is the board around the outside edge of a floor frame, capping the ends of the joists and sitting on the sill plate.Shared with RoofingRoof trussA roof truss is a factory built triangle of lumber joined with metal plates.
S
CarpentryScribingScribing is tracing an irregular surface, like a wavy wall or floor, onto a piece of trim, cabinet or countertop and cutting it to match.Shared with HandymanShimA shim is a thin tapered piece of wood or plastic slid into a gap to level, plumb or pack out a door, window, cabinet or appliance.CarpentryShiplapShiplap is boards with a rabbeted edge on each side so they overlap, leaving a small reveal line between boards.CarpentrySill plateThe sill plate is the board laid flat on top of the foundation wall, bolted down, that the floor framing or wall sits on.CarpentryStair nosingThe nosing is the front edge of a stair tread that sticks out past the riser below.CarpentryStair rise and runRise is the height of each step and run, or tread depth, is its depth.CarpentryStair stringerStringers are the notched or housed boards on each side, and sometimes the middle, of a stair that carry the treads and risers.CarpentryStudA stud is one of the vertical framing members in a wall, running from the bottom plate to the top plate.Shared with FlooringSubfloorThe subfloor is the structural layer of plywood, OSB or boards fastened to the joists, under the finished flooring and any underlayment.
T
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