Architrave is the strip of moulding that runs up both sides of a door opening and across the top. It is the most-seen and least-thought-about piece of joinery in a house, and it is the difference between a door that looks fitted and a door that looks installed. This guide covers what architrave actually does, the profiles and materials you can buy, how to size it, the margin you set it to, and how to cut and fix it so the mitres stay closed.
Short answer
Architrave covers the junction between the door lining and the plaster. Buy it slightly thinner than your skirting so the skirting can meet it cleanly, set it back from the inside face of the lining by a consistent 6mm to 10mm margin, cut the corners at 45 degrees with a mitre saw, and fix it with pins and adhesive. We hold 16 products in our door architraves range and 16 in skirting.
What an architrave actually is
The joint it covers
When a door lining is fitted into a structural opening there is always a gap between the timber lining and the plaster or plasterboard around it. That gap is never neat, it moves slightly as the building settles, and it cannot be filled reliably. Architrave covers it. Everything else architrave does is secondary to that one job.
Architrave, lining and frame
The lining is the timber box that the door hangs in. The frame is the heavier equivalent used on external openings. The architrave is the decorative moulding fixed over the outside edge of either one. They are three different things and they are bought separately. We hold over 30 products in internal frames and linings and 2 in external frames.
It is not an arch
The word architrave has nothing to do with arches. It comes from classical architecture, where it described the lowest band of an entablature sitting directly on the columns. A straight run of moulding around a rectangular opening is still an architrave.
What it does not do
Architrave does not stop draughts. Draughts come around the door leaf itself, through the gap between the door and the lining, and they are dealt with by seals fitted to the lining or the door. Our guide on draughty doors covers the actual fixes. Architrave also does not protect the door. It protects the plaster edge of the reveal, which is the most easily damaged part of any opening.
The parts of an architrave set
The two legs
The vertical pieces. On a standard 1981mm opening these need to be a little over 2.1m long once you allow for the margin at the top and the cut at the floor. Most architrave is sold in lengths that give you a leg with a little to spare.
The head
The horizontal piece across the top. It is mitred at both ends to meet the legs. On a standard 762mm door the head is around 900mm once the margins and the mitres are accounted for.
How much you need per opening
One side of one opening takes two legs and one head. If the opening is visible from both rooms, and most internal openings are, you need that twice. Working out your order in sides rather than doors is the single easiest way to avoid coming up short.
Plinth blocks
A plinth block is a thicker, taller block fitted at the bottom of each leg. Its job is to give a thick skirting board something square to die into, rather than trying to scribe a heavy skirting profile against a thin moulded architrave. In period properties they are often a design feature in their own right.
Rosette or corner blocks
Square blocks fitted at the top corners so the legs and head butt into them rather than being mitred together. They suit Victorian and Edwardian interiors and they remove the mitre from the equation entirely, which is worth knowing if your walls are badly out of true.
Profiles: the shapes you can buy
Ogee
An S shaped curve, concave at the top and convex at the bottom. The most common traditional profile in British housing and the safest choice if you are matching existing joinery in a Victorian or Edwardian house.
Torus
A single bold convex bead. Heavier looking than ogee and very common in twentieth century housing. It reads as traditional without being fussy.
Chamfered
A flat face with an angled edge. Simple, cheap, and a good match for mid century and plain modern interiors. It is also the least likely profile to collect dust.
Pencil round
A flat face with one softly rounded edge. The quiet default in new build housing. It suits almost anything and draws no attention to itself, which is often exactly what you want.
Bullnose
A flat face with a fully rounded edge, more pronounced than pencil round. Slightly softer and slightly more traditional feeling.
Square edge
Completely flat with sharp arrises. The right choice for contemporary and minimal interiors, particularly alongside flush doors and shadow gap detailing. It is the least forgiving profile to fit, because a flat face shows every gap.
Choosing a profile for your property
Match the age of the house rather than the fashion of the moment. A square edge architrave in a 1900s terrace with deep ogee skirting will look like a mistake, and a heavy Victorian profile in a new build flat will look like fancy dress. If some original joinery survives anywhere in the house, copy it.
Materials
Primed MDF
The default for painted architrave. It is stable, it machines to a crisp profile, it does not have knots that bleed through paint, and it arrives ready for a topcoat. Its weakness is water, so it is a poor choice anywhere it will get repeatedly wet.
Softwood
Pine and other softwoods take a stain or a paint finish and are easy to work. Knots need sealing with a knotting solution before priming or they will telegraph through the paint within a year.
Oak and hardwood
Solid oak architrave is the right partner for oak doors, and it is the only material on this list that looks better after twenty years. It is harder to cut cleanly, it needs pilot holes for every fixing, and it costs several times what MDF costs. We hold over 290 products in internal oak doors if that is the look you are building towards.
Veneered and foil wrapped
A core wrapped in a real veneer or a printed foil to match a prefinished door. Useful when you are matching a specific door finish exactly, but the wrap can be damaged by heavy handed fixing and it cannot be sanded back.
What the older version of this article got wrong
The previous version listed plaster and metal as common architrave materials and suggested pairing wooden doors with metal frames. In a UK domestic setting architrave is timber, MDF or a wrapped board. It also suggested skirting boards and picture rails as a cheaper alternative to architrave. They are not alternatives. They do completely different jobs in different places, and none of them will cover the lining junction around a door.
Sizing: getting the dimensions right
Face width
The face width is how much wall the architrave covers. Common widths run from around 55mm up to 95mm and beyond. Narrow architrave suits small rooms, low ceilings and modern interiors. Wide architrave suits high ceilings and period proportions, and it needs the wall space either side of the opening to carry it.
Thickness
Thickness is how far the architrave stands off the wall. Typical thicknesses sit around 15mm to 25mm. This number matters more than most people realise, because it dictates how the architrave meets the skirting.
Why architrave must be thinner than skirting
Skirting runs along the wall and stops when it reaches the architrave. If the skirting is thicker than the architrave, it can be cut square and butted straight into the side of the architrave with a clean shadow line. If the architrave is thicker than the skirting, you are left with a step and no tidy way to finish it. Always order skirting at least as thick as the architrave, and preferably a little thicker.
Matching the scale of the room
Architrave, skirting and any picture rail should read as a family. A 70mm architrave with a 220mm skirting looks mean. A 95mm architrave with a 95mm skirting looks like the skirting has been forgotten. As a rough guide the skirting is usually noticeably deeper than the architrave is wide.
Ceiling height
Rooms with high ceilings carry wider mouldings comfortably. In a room with a 2.4m ceiling, a very wide architrave crowds the door and makes the ceiling feel lower. Measure the wall between the top of the opening and the ceiling before you choose a width, because that gap is where a wide architrave causes problems.
The margin explained
What a margin is
The margin, sometimes called the reveal, is the strip of lining left visible between the inside edge of the lining and the inside edge of the architrave. Architrave is never fixed flush to the inside face of the lining.
The usual figure
Somewhere between 6mm and 10mm is standard. Smaller looks tight and leaves no room for error. Larger starts to look like a deliberate design decision, which is fine if that is what you intended.
Keeping it consistent
The single most visible mistake in architrave fitting is a margin that varies. The eye picks it up instantly even if it cannot name it. Set a small offcut of timber to your chosen margin and use it as a gauge all the way round, rather than measuring each mark with a tape.
Where hinges and the strike interfere
Check that your margin leaves room for the hinge knuckles and the strike plate. On a lining that has been fitted tight into an opening, a generous margin can bring the architrave into contact with the door as it swings past. Test the door before you fix anything permanently. Our guide on where to fit door hinges covers the setting out.
Fitting architrave step by step
1. Finish the lining and the plaster first
The lining must be plumb, square and flush with the plaster on both faces. Architrave will not hide a lining that stands proud of the wall, and it will not straighten a lining that is out of plumb. Fix the opening first.
2. Mark the margin
Pencil the margin line up both legs and across the head using your gauge block. Take an extra minute over this, because every cut that follows references these lines.
3. Cut and fit the head first
Cut the head to length with a 45 degree mitre at each end and offer it up to the margin line. Fixing the head first means that if the opening is slightly out of square, the discrepancy ends up at the floor where a small adjustment is invisible, rather than at eye level in the mitre.
4. Cutting the mitres
Both cuts are at 45 degrees, and the two pieces meeting at a corner must be cut on opposite bevels. Cut slightly long and creep up on the fit. Every millimetre you take off a mitre changes the length of the piece, so trimming a tight mitre also shortens the leg.
5. Scribing to the floor
Floors are rarely level. Rather than leaving a wedge shaped gap under one leg, hold the leg in position, set a compass or a small block to the largest gap, and scribe a line along the bottom that follows the floor. Cut to that line and the leg sits down tight.
6. Fixing
A bead of grab adhesive on the back plus lost head nails or pins into the lining and into the studwork behind the plaster. Adhesive alone will let go of a wall that flexes. Nails alone will let the mitre open as the timber moves. Both together is what keeps a mitre closed for twenty years.
7. Walls that are not flat
If the plaster falls away from the lining, the architrave will rock and the mitre will open. Pack behind the architrave with slivers of card or thin packers before you fix it, so it is supported along its whole length rather than bridging a hollow.
8. Filling and caulking
Punch the nail heads below the surface and fill them. Fill the mitre joint itself if it has opened even slightly. Then run a fine bead of decorator's caulk along the junction between the outer edge of the architrave and the wall, and tool it off. That caulk line is what makes the whole thing look like it grew there.
Tools
A mitre saw
A powered mitre saw, or a decent mitre box and a sharp fine toothed saw, is the essential tool. Accuracy at 45 degrees is the entire job.
Why a jigsaw will not do
The previous version of this guide suggested renting a jigsaw. A jigsaw cannot hold a straight line, cannot hold an accurate 45 degree bevel, and its blade wanders off square through the thickness of the timber. It is the wrong tool for this job in every respect. Use a mitre saw.
Marking and measuring
Tape measure, sharp pencil, combination square, and a gauge block cut to your margin. A small spirit level is useful for checking the head before you fix it.
Fixing
Grab adhesive, lost head nails or a second fix nailer, a nail punch, and a drill with a fine pilot bit if you are working in oak.
Finishing
Two part or lightweight filler, decorator's caulk and a caulking gun, fine abrasive, and a damp cloth for tooling the caulk.
Where architrave meets skirting
The thickness rule again
Skirting thicker than architrave, always. Then the skirting is simply cut square and butted into the architrave leg.
Plinth blocks as the solution
If you have inherited a heavy period skirting and want a slim architrave, a plinth block solves the problem cleanly. The skirting butts into the block, the architrave sits on top of it, and no scribing is needed.
Scribing the skirting
Where the skirting is thinner than the architrave and you cannot change either, the skirting has to be scribed to the architrave profile. It is fiddly, it never looks quite right on a moulded profile, and it is why the thickness rule exists.
Painting and finishing
Primed MDF
The factory primer is a base coat, not a finish. Sand it lightly, fill and caulk, then apply two topcoats of a water based trim paint. Do this after fixing, not before, because you will be filling nail holes and mitres afterwards anyway.
Softwood
Seal any knots with a knotting solution first, then prime, then two topcoats. Skipping the knotting is why so many painted softwood mouldings develop brown patches.
Oak and hardwood
Oak architrave is normally finished with a clear lacquer, oil or hardwax to match the doors. Sand with the grain, keep the finish thin, and treat the end grain at the mitres, which absorbs far more finish than the face.
Matching the door or contrasting it
Painting the architrave the same colour as the wall makes an opening recede and a small room feel larger. Painting it the same colour as the door makes the opening read as a single object. Painting it white against a coloured wall is the traditional approach and still the safest. Our guide on painting an interior door covers the finishes.
The caulk line
Caulk the wall junction, but do not caulk the mitre. Mitres want filler, which can be sanded flush. Caulk stays flexible and will not sand, so a caulked mitre always shows.
Costs
What drives the price
Material first, profile complexity second, and width third. Primed MDF in a simple profile is the cheapest route to a good result. Solid oak in a period profile can cost many times more per metre.
Working out how much you need
Per side of a standard 1981mm by 762mm opening, allow roughly 2.2m for each leg and 1m for the head, so around 5.4m per side and around 10.8m for an opening finished on both faces. Add 10 percent for cutting waste and for the mitre you get wrong.
Where people overspend
Buying architrave and skirting from different ranges and then discovering the profiles do not relate. Buying solid oak for openings that are going to be painted anyway. Buying short lengths that force extra joints into a leg. Order the full set for the whole floor in one go.
Common mistakes
An inconsistent margin
Use a gauge block, not a tape measure.
Mitres cut on the same bevel
The two halves of a corner are mirror images. Cutting both on the same bevel is the classic first timer error and it wastes a full length.
Nailing without adhesive
The mitre opens within a season. Use both.
Architrave thicker than the skirting
There is no tidy way out of this once both are bought. Check before ordering.
Fitting before the plaster has dried
Fresh plaster carries a lot of moisture. MDF and softwood fixed against it will move as it dries and the mitres will open.
Forgetting the door has to open
Check the swing with the architrave held in position, particularly on the hinge side and where a handle may hit the moulding.
Cutting the legs before the head
Fit the head first and let any error in the opening run out at the floor.
Cleaning and maintenance
Painted architrave
Dust with a soft brush or a vacuum brush attachment. Marks come off with a damp cloth and a mild detergent. Avoid abrasives and solvents, which cut straight through a trim paint. See our product care advice.
Oak architrave
Dust regularly and refresh the oil or hardwax when the surface starts to look dry. Our guide on cleaning and maintaining oak doors applies equally to oak mouldings.
Chips and dents
On painted MDF, fill, sand and touch in. On oak, a small dent can often be raised with a damp cloth and a warm iron before you refinish. Keep a metre of spare architrave from the original order, because matching a profile years later is close to impossible.
Architrave and fire doors
Architrave is decorative and sits outside the fire rated assembly, so on its own it does not carry a rating. What matters is that the architrave does not obstruct the intumescent seals, does not interfere with the door closing fully, and that the gap between the lining and the structural opening is packed and sealed as the doorset specification requires. Confirm the detail with the doorset manufacturer or building control rather than assuming. We hold over 240 products in fire doors, over 150 in FD30 fire doors and 11 in intumescent strips and pads.
Frequently asked questions
What is the standard architrave margin?
Between 6mm and 10mm from the inside edge of the lining, kept identical all the way round.
Should architrave be thicker or thinner than skirting?
Thinner, so the skirting can butt cleanly into it.
What angle do you cut architrave?
45 degrees at each corner, with the two meeting pieces cut on opposite bevels.
Do I fit the head or the legs first?
The head first, so any error in the opening runs out at floor level.
How much architrave do I need per door?
Around 5.4m per side, so around 10.8m for an opening finished on both faces, plus 10 percent waste.
Can I fit architrave with a jigsaw?
No. Use a mitre saw or a mitre box.
Does architrave stop draughts?
No. Draughts come around the door leaf. Fit seals to the lining instead.
Do I have to use plinth blocks?
No, but they are the neatest solution when the skirting is much thicker than the architrave.
Can I paint architrave before fitting it?
Prime it beforehand if you like, but leave the topcoats until after fixing, filling and caulking.
Does architrave need to match the door?
It needs to relate to it. Matching exactly is one valid option, painting it to match the walls is another, and white against a coloured wall remains the traditional choice.
Related ranges and guides
The opening
We hold over 30 products in internal frames and linings, 16 in door architraves and 16 in skirting. Our guide on measuring a door and the door size guide cover sizing the opening itself.
The door
We hold over 710 products in internal doors, over 350 in fully finished internal doors, over 80 in internal white primed doors, over 280 in glazed doors and over 250 across the Deanta range.
Fitting
See how to plane a door and where to fit door hinges. We hold over 350 products in door hinges and over 2,900 across door hardware.
Walls and panelling
If you are detailing a whole room, our wall panelling guide covers how panelling relates to skirting and architrave, and we hold 15 products in wall panelling and 10 in acoustic wall panels.
Why buy your architrave from Doors2Floors
We have supplied doors and flooring to homes and businesses across the UK. Buying the door, the lining, the architrave and the skirting from one supplier means the profiles relate to each other and everything arrives together, which matters more on this job than on almost any other. If you are unsure which profile suits your property, talk to our team before you order.
Wide openings and double doors
Architrave detailing gets more demanding on a pair, because the two leaves meet in the middle and any inconsistency in the surround is immediately visible. If you are creating that pair from two single leaves, the rebate kit comes from pair makers, and it is worth setting out the architrave and the lining together before either is fixed.
Where architrave is being fitted around a fire doorset, confirm the detail with the doorset manufacturer's certification and with your local building control body or a competent professional. The guidance above is general and does not replace advice specific to your building.