The Column
A classical column is a stack of named parts with fixed proportions. Doors, mantels and walls borrow the same stack, so learn it once here.
- Pedestal
- The block the column stands on.
- Column
- The round post itself: base, shaft, capital.
- Entablature
- Everything the column holds up; a decorated beam.
- Order
- One whole set, pedestal to cornice, with its own rules of proportion. Tuscan is the plainest of five.
- Cornice
- The top part that sticks out, like the brim of a hat. It throws rain and shadow.
- Frieze
- The flat band in the middle.
- Architrave
- The beam at the bottom, resting on the columns.
- Abacus
- The square slab on top.
- Echinus
- The cushion that flares out under the slab.
- Necking
- The plain band just below.
- Capital
- Abacus, echinus and necking together: the column’s head.
- Shaft
- The long round body.
- Entasis
- The shaft’s slight bulge. A dead-straight shaft looks pinched in the middle.
- Torus
- The fat round ring at the foot.
- Base plinth
- The square pad under the ring.
- Cap
- Its little cornice.
- Die
- The plain block in the middle.
- Plinth
- Its foot.
- D, the diameter
- The shaft’s width at the bottom. Every other size is counted in D’s: this column is 7 D tall.
On the job. When you set or wrap a column, the shaft sits centered on its base and the beam above lands on the capital, not beside it.
The Eight Moldings
A molding is a strip with a shaped edge. Every crown, casing and baseboard is some mix of these eight shapes, shown here mounted on a board with the cut ends facing you.
- Molding
- A long strip of wood, plaster or stone with a shaped face.
- Profile
- The outline you see if you slice a molding straight through. The pale end of each piece here.
- Section
- Any drawing of a thing as if sliced through.
- Fillet
- A small flat band. It separates the curves so each one reads.
- Bead
- A small half-round, like a pencil laid on the surface. Around a column it’s called an astragal.
- Torus
- A big half-round, like a tire. The ring at a column’s foot.
- Ovolo
- A quarter-round that bulges out. It catches the light.
- Cavetto
- A quarter-round scooped in; also called a cove. It holds shadow.
- Scotia
- A deep scoop between two flat bands. The dark line in a column base.
- Cyma recta
- An S-curve, scooped on top and bulging below. The usual top of a crown.
- Cyma reversa
- The S the other way up. Also called an ogee.
- Convex and concave
- Convex bulges out and catches light. Concave scoops in and holds shadow. Good trim alternates the two.
- Built-up
- A big molding made by stacking several small ones.
On the job. Name the profile before you order or match it. A photo of the cut end next to a tape is the fastest way to match existing trim.
Trim Around a Door
Trim is the wood that covers the joint where a door frame or a ceiling meets the wall. Each piece stands a little proud of the one behind it, and that step is what you judge.
- Jamb
- The door frame; the wood the door closes into.
- Casing
- The flat trim around the frame, like a picture frame around the doorway.
- Reveal
- The thin strip of frame left showing beside the casing, about 3/16 in. It should be the same width all the way round.
- Door gap
- The space between door and frame, about 1/8 in., so the door can swing.
- Back band
- An extra strip wrapped around the outside edge of the casing to make it look thicker.
- Plinth block
- A thick block at the foot of the casing. The baseboard runs into it.
- Baseboard
- The board along the bottom of the wall.
- Base cap
- The shaped strip on top of the baseboard.
- Shoe
- A small strip at the floor that hides gaps. Good floors don’t need one.
- Miter
- Two pieces each cut at 45° so they meet in a neat diagonal line.
- Cope
- One molding cut to fit over the shape of the other. Used at inside corners because it doesn’t open up.
- Crown
- The molding where wall meets ceiling. It leans out, leaving a hollow behind it.
- Spring angle
- How far the crown leans away from the wall: 38° or 45°.
On the job. Set the reveal with a gauge block and keep it the same on both legs and the head before you nail.
A Paneled Wall
A traditional wall is divided like a column: a heavy base, a plain middle and a decorated top. The wood panels at the bottom are built to move.
- Crown
- The molding at the ceiling.
- Frieze
- The plain band of wall just under the crown.
- Picture rail
- A thin molding you can hang pictures from. It also makes a tall room feel lower.
- Chair rail
- A molding at about chair-back height. It tops the paneling.
- Wainscot
- Wood paneling on the lower part of a wall.
- Dado
- The lower part of the wall, from the floor to the chair rail.
- Baseboard
- The board along the floor.
- Stile
- An upright piece of the frame.
- Rail
- A piece of the frame that runs side to side.
- Panel
- The board that fills the frame.
- Field
- The flat middle of a panel.
- Bevel
- The sloped edge around the field. A panel with one is a raised panel.
- Floating
- The panel sits loose in a groove and isn’t glued, so it can swell and shrink without cracking.
- The wall as a column
- Paneling is the pedestal, about a fifth of the height. Frieze and crown are the entablature, about a sixth. Most rooms use a lighter top.
On the job. Lay out panels from the center of the wall so the two end panels match.
From Log to Board
How a board behaves is decided by where it sat in the tree. Scroll to saw this oak log into slabs, then pull three boards out of it: the same wood cut three ways, with three different faces. Every grain line you see is where a growth ring meets the saw.
- Growth rings
- One ring for each year the tree grew.
- End grain
- The cut end of a board, where you can see the rings.
- Heartwood
- The darker, older wood in the middle. It lasts longest.
- Sapwood
- The paler young wood just under the bark.
- Plain-sawn
- Sliced straight across the log. The cheapest cut, with arched grain on the face.
- Cathedral grain
- Those arches, like pointed church windows.
- Rift-sawn
- Sliced so the rings cross the board on a slant. Straight, quiet grain.
- Quartersawn
- Sliced so the rings stand straight up in the board. The steadiest cut.
- Ray fleck
- Shiny ribbon-like marks in quartersawn oak.
- Movement
- Wood swells in damp air and shrinks in dry air, for as long as it exists.
- The 2-to-1 rule
- It moves about twice as much along the rings as across them, and hardly at all along its length.
- Cupping
- A board curling across its width as one face dries faster than the other.
On the job. Read the end grain before you place a board. Put rift or quartersawn stock where movement would show.
Three Joints
A joint has to hold two pieces together and still let the wood swell and shrink. These three, which pull apart as you scroll so you can see inside, do most of the work in a fine house.
- Tenon
- The tongue.
- Mortise
- The pocket.
- Shoulder
- The flat step around the tongue. It stops the frame from wobbling.
- Stile and rail
- The upright piece and the crosswise piece of any frame.
- Tail
- A wedge shaped like a bird’s fanned tail.
- Pin
- The piece between two tails.
- Through dovetail
- One you can see from both sides.
- Half-blind
- One hidden from the front, as on a drawer face.
- End grain
- The cut ends of the fibers. Glue holds badly, so joints are shaped to avoid relying on it.
On the job. Dry-fit every joint before glue. If it needs a clamp to close, it is not fitted yet.
The Stair
A stair is the hardest thing a finish carpenter builds, and the building code fixes most of its sizes. White risers and oak treads are shown so you can tell them apart.
- Tread
- The flat part you step on.
- Riser
- The upright board between two treads.
- Nosing
- The front edge of a tread, where it sticks out past the riser.
- Rise
- The height of one step.
- Run
- The depth of one step, front edge to front edge.
- Stringer
- The sloped board down the side that carries the steps.
- Landing
- A flat floor at the top of a flight or at a turn.
- Handrail
- The rail you hold.
- Baluster
- One of the thin posts under the rail.
- Balustrade
- The whole railing: posts, balusters and rail.
- Newel
- The big post at the bottom, top or turn of the stair.
- Gooseneck
- The bend where the rail rises to meet a taller post.
- Guard
- A railing whose job is to stop a fall from a landing or balcony.
- Why they’re fixed
- Feet learn a stair in two steps. One odd step trips people, so the code limits every size and allows almost no variation.
- Headroom
- The clear height above the steps.
On the job. Measure every rise before you cut. Under the residential code the tallest and shortest riser in a flight may differ by no more than 3/8 inch.
The Roof
A roof is a few sloped planes, and the lines where they meet all have names. Beside the house: how two-piece clay tile fits together.
- Ridge
- The level line along the very top, where two slopes meet.
- Hip
- A sloped outside corner, where two slopes meet and point outward.
- Valley
- A sloped inside corner. Water gathers here, so it leaks first.
- Eave
- The low, level edge of the roof.
- Gable
- The triangle of wall under two slopes.
- Rake
- The sloped edge of the roof at a gable.
- Pitch
- How steep the roof is.
- Rafter
- One of the sloped beams that hold the roof up.
- Rafter tail
- The end of a rafter where it sticks out past the wall.
- Fascia
- The board nailed across the ends of the rafters.
- Soffit
- The underside of the overhang.
- Gutter
- The trough that catches the water.
- Overhang
- How far the roof sticks out past the wall.
- Pan
- A tile laid like a trough; it carries the water.
- Cover
- A tile laid like a cap over the gap between two pans.
- Two-piece mission tile
- Pans and covers as separate tiles. The traditional Santa Barbara roof.
- S-tile
- A one-piece shortcut: pan and cover molded together.
On the job. Know these names so you can tell the roofer exactly where a leak or a trim problem is.
Wood Moves
Wood swells when the air is damp and shrinks when it is dry, and it never stops. Scroll to dry the room out and watch what good joinery does about it.
- Floating panel
- A panel that sits loose in grooves, with no glue, so it can shrink and swell without cracking.
- Groove
- The slot in the frame that the panel edge hides in. It is cut deeper than the panel needs, to leave room to move.
- Rail
- A horizontal piece of the frame. It lifts here so you can see the panel edge inside its groove.
- Miter
- Two pieces cut at 45° to meet at a corner. When the wood shrinks, the inside of the joint opens into a gap.
- Cope
- One piece cut to the exact shape of the other and lapped over it. When the wood shrinks the corner stays closed.
- Cupping
- A board curling across its width as it dries, like a shallow trough. Plain-sawn boards do it most.
On the job. Let trim and panels sit in the house before install, and never glue a panel into its frame.
The Arch
An arch carries weight over an opening by turning it into squeeze. Every wedge-shaped stone pushes on its neighbors, and the last stone in locks them all.
- Keystone
- The wedge at the very top. It goes in last and locks the others in place.
- Voussoir
- Any one of the wedge-shaped stones that make the arch. Say voo-SWAR.
- Springer
- The lowest stone on each side, where the curve starts.
- Impost
- The block on top of the pier that the arch sits on.
- Pier
- The solid upright that carries the arch down to the ground.
- Intrados
- The inside curve of the arch; the underside you look up at.
- Extrados
- The outside curve, along the backs of the stones.
On the job. Arched casings are laid out from the springing line, where the curve starts. Mark it level on both sides first.
The Window
A traditional window is a frame of glass set inside a frame of wood, then trimmed like a door. Seen here from inside the room; scroll and it comes apart toward you.
- Sash
- The frame that holds the glass. It is the part that moves when a window opens.
- Muntin
- A thin bar that divides the glass into smaller panes.
- Lite
- One pane of glass. A true divided lite window has a separate pane in every opening.
- Jamb
- The frame lining the opening in the wall. The sash sits inside it.
- Casing
- The flat trim around the window that covers the gap between the jamb and the wall.
- Stool
- The flat shelf at the bottom on the inside. Most people call it the sill, but the sill is outside.
- Apron
- The trim board under the stool.
- Sill
- The sloped piece at the bottom on the outside. It sheds rain away from the wall.
On the job. The stool goes in first, the casing sits on it and the apron goes on last.
Inside a Plaster Wall
A plaster wall near the ocean is a stack of layers, and each one has one job: hold the house up, keep water out, or let it drain. Seen from outside; scroll to peel the layers apart.
- Stud
- An upright framing piece inside the wall, usually 16 inches apart.
- Sheathing
- Plywood nailed across the studs. It stiffens the wall and gives everything else a backing.
- Water-resistive barrier
- Building paper or wrap over the sheathing. Water that gets through the plaster runs down it instead of into the wood. Often called the WRB.
- Drainage gap
- A thin air space behind the plaster so trapped water can drain and the wall can dry.
- Lath
- Wire mesh fastened over the wall that gives wet plaster something to grip.
- Scratch coat
- The first coat of plaster, pushed into the lath and scored with lines so the next coat grips.
- Brown coat
- The second coat, trowelled flat. It makes the wall straight and true.
- Finish coat
- The thin last coat. Its color and texture are what you see.
- Weep screed
- A metal strip along the bottom edge of the plaster with holes that let water drain out.
On the job. Anything fastened through exterior plaster is a hole in the water barrier. Seal it and flash it.
The Eave, Cut Through
The eave is where the roof runs past the wall. Sliced open, it is a short stack of parts with one job between them: get rain off the roof and away from the wall. Many Spanish-style houses leave the rafter tails showing; this one is boxed in so you can see every piece.
- Rafter
- One of the sloped beams that hold the roof up.
- Rafter tail
- The end of a rafter that sticks out past the wall.
- Top plate
- The flat timber along the top of the wall that the rafters sit on.
- Roof deck
- The boards or plywood nailed over the rafters. The tile sits on it.
- Fascia
- The board across the ends of the rafter tails. The gutter hangs on it.
- Soffit
- The flat underside of the overhang, closing in the rafter tails.
- Gutter
- The trough that catches water running off the roof edge.
- Overhang
- How far the roof sticks out past the wall. It shades the windows and keeps rain off the plaster.
On the job. Prime every cut end of fascia and trim before it goes up. End grain takes in water first.
Three Cabinet Doors
The same box can wear its door three ways, and the choice sets the look and much of the cost. Scroll to pull the doors off and see what each one sits on.
- Carcass
- The plain box of a cabinet, before doors and trim. Also spelled carcase.
- Face frame
- A frame of solid wood fixed to the front of the box. The doors hang on it.
- Inset
- The door sits inside the face frame, flush with it. Every flaw in the fit shows, so it is the hardest to build and the most expensive.
- Partial overlay
- The door sits on top of the face frame and covers part of it, leaving frame showing all round.
- Frameless
- No face frame at all. The door covers the whole front of the box. Also called European or full overlay.
- Reveal
- The even gap around an inset door. Usually between 1/16 and 1/8 inch. What matters is that it is the same all the way round.
On the job. Inset doors are fitted one at a time. Allow the hours for it.
Scribing
No wall is flat or truly upright, so a board cut square will always show a gap against it. Scribing copies the wall onto the board. Scroll to trace the line, drop the waste and slide the board home.
- Scribe line
- The pencil line that copies the shape of the wall onto the board.
- Compass
- The tool that does the tracing. One point rides the wall while the pencil marks the board a fixed distance away.
- Waste
- The sliver cut off along the line.
- Out of plumb
- Not truly vertical. Walls also bulge and dip, which is why trim is scribed and not just cut square.
- Scribe
- To trace an uneven surface onto a board, then cut to the line so the two fit with no gap.
- Back-bevel
- Leaning the cut in a few degrees so only the front edge touches the wall. It makes a tight fit easier.
On the job. Scribe to the wall. Do not caulk a gap you could have cut out.
Crown at a Corner
Crown molding does not sit flat. It leans across the corner between wall and ceiling, with a hollow behind it. Scroll to drop it away and see what it is fixed to.
- Crown
- The molding that covers the joint between wall and ceiling.
- Spring angle
- The angle the crown leans out from the wall. Common crowns are made at 38 or 45 degrees, and every cut depends on it.
- Cope
- At an inside corner, one piece runs square into the corner and the other is cut to its shape and laps over it.
- Backing
- A strip or blocks fixed in the corner behind the crown, so there is solid wood to nail into.
- Projection
- How far the crown reaches out across the ceiling.
- Drop
- How far the crown comes down the wall.
- Outside miter
- At an outside corner both pieces are cut at an angle and meet at a point. Outside corners are mitered, inside corners are coped.
On the job. Cope inside corners and miter outside corners. Test the fit on scrap first.
A Three-Piece Baseboard
A tall baseboard is usually built from three pieces, so each one can follow the wall or the floor on its own. Scroll to lift them apart and open the joint in the long run.
- Baseboard
- The flat board along the bottom of the wall.
- Base cap
- The small shaped molding on top of the baseboard. It bends to follow a wavy wall.
- Shoe
- The small rounded strip at the floor. It bends to follow an uneven floor and hides the gap.
- Scarf joint
- Two boards joined end to end on a long slant, so the seam stays closed when the wood shrinks.
- Miter return
- A tiny mitered piece that turns the profile back into the wall, so no end grain shows where a molding stops.
On the job. Join long runs with a scarf joint over a stud, glued and nailed.
The Mantel
A fireplace mantel is the classical column and beam again, at furniture scale: two legs, a beam across and a shelf on top. Scroll to pull it off the wall.
- Mantel shelf
- The flat top you set things on.
- Bed mold
- The molding tucked under the shelf, easing it into the board below.
- Frieze
- The wide flat board across the top, under the shelf.
- Pilaster
- A flat column fixed to the wall. Here, the legs of the mantel.
- Plinth
- The plain block at the foot of each leg.
- Surround
- The band of stone or tile around the opening. It must not burn, because it is closest to the fire.
- Hearth
- The stone floor in front of the fire.
- Firebox
- The chamber where the fire burns.
On the job. Wood trim has to stay a set distance from the firebox opening. Check the code clearance before layout.
A Built-In Bookcase
A built-in is a plain box set level and plumb, then dressed so it looks like part of the house. Scroll to pull off the trim and slide the shelves out.
- Carcass
- The plain box: two sides, a top and a bottom.
- Face frame
- The frame fixed to the front of the box. It hides the plywood edges and stiffens the case.
- Adjustable shelf
- A loose shelf that rests on pins and can be moved up or down.
- Shelf pins
- Small pegs that fit a row of holes in the sides and carry the adjustable shelves.
- Fixed shelf
- A shelf joined to the sides. It stops a tall case from bowing.
- Toe kick
- The recessed board at the floor that lets your feet stand close.
- Filler strip
- A strip left wide, then scribed to the wall, to close the gap between a square box and an uneven room.
- Crown
- The molding across the top that ties the case to the ceiling or finishes it off.
- Back
- The thin panel that closes the back and keeps the box square.
On the job. Set the box level and plumb on shims first. The face frame and filler strips hide the gaps to the room.
Hanging a Door
A door frame is not nailed tight to the wall framing. It floats in a slightly bigger hole and is wedged true with shims. Scroll to swing the door and slide the shims out.
- King stud
- The full-height stud on each side of the opening.
- Trimmer
- The shorter stud beside the king stud that carries the header. Also called a jack stud.
- Header
- The beam across the top of the opening that carries the wall above.
- Rough opening
- The framed hole in the wall, made a little bigger than the door frame so there is room to adjust.
- Shim
- A thin wedge slipped between the frame and the framing to make the jamb straight and plumb.
- Jamb
- The door frame itself: two sides and a head.
- Hinge
- The pivot the door swings on. Each leaf is let into a shallow recess called a mortise so it sits flush.
- Stop
- The strip the door closes against.
- Strike plate
- The metal plate on the jamb that the latch clicks into.
- Margin
- The even gap between the door and the jamb. On a well-hung door it is the same on all three sides.
On the job. Plumb the hinge side first. Shim behind each hinge and at the strike, check the margin is even, then fix.
A Drawer
A drawer is a small box that gets pulled thousands of times, so everything about it is built around that pull. Scroll to take the front off and drop the bottom out.
- Drawer front
- The show face. Here it is a separate piece fixed to the box, so it can be adjusted to line up.
- Side
- The long pieces of the box that the slides fix to.
- Drawer box
- The four-sided box behind the front. On good work its corners are dovetailed.
- Bottom
- The thin panel that slides into grooves in the sides. It is left unglued so it can move.
- Groove
- The slot near the bottom edge of the sides that holds the drawer bottom.
- Slide
- The metal runner the drawer rides on. Side-mount slides show when the drawer is open; undermount slides hide beneath it.
On the job. Fit the box to its slides first, then set the drawer front to its reveal with spacers.
Four Wall Treatments
Four common ways to dress a wall in wood. They look alike from across a room and are built quite differently. Scroll to pull a piece off each.
- Board and batten
- Wide flat panels with narrow strips over the seams.
- Batten
- One of the narrow strips.
- Beadboard
- Narrow boards with a small rounded bead along each joint.
- Cap
- The molding that finishes the top edge of a wainscot.
- Shiplap
- Boards with stepped edges that overlap, laid here on the flat.
- Nickel gap
- The thin, even shadow line left between boards, about the thickness of a nickel.
- Box molding
- Thin molding fixed to a flat wall in rectangles to look like panels. Also called picture-frame molding.
On the job. Find and mark the studs before layout, and plan the spacing so no sliver ends up in a corner.
Beams, Corbels and Rafter Tails
The heavy dark timber of Spanish-style houses: beams that carry, brackets that hold them and shaped rafter ends left on show under the eave.
- Beam
- A heavy timber that carries load across a span. Many decorative beams are hollow boxes made of three boards.
- Corbel
- A shaped bracket that sticks out from the wall to hold up a beam.
- Rafter tail
- The end of a rafter left showing past the wall.
- Tail cut
- The decorative shape sawn into the end of an exposed rafter tail.
- Roof deck
- The boards laid over the rafters. With open eaves you see their underside, so they are chosen for looks.
- Box beam
- A hollow beam built from boards to look like solid timber. Lighter, straighter and cheaper than the real thing.
On the job. Seal every face of exterior timber before install, especially end grain and the top.