Carpentry work: cost per piece 2026 and the process

In a renovation, the joiner almost always arrives near the end. The reason is simple: timber and wood-based materials change with the moisture in the air. If plaster, screed or skim coats are still drying in a room, lining frames, doors, skirting, cladding and fitted wardrobes do not belong there yet. As a rough guide, cement screed dries for about a week per centimetre of thickness, and longer if the layer is thick or the weather is cold. Do not rely on the calendar alone, though. The floor layer can measure the actual moisture in the screed with a meter.

The usual order runs like this: wet trades first, then the floor, then decorating, and only at the end frames, doors and skirting. The exception is a steel door frame, which goes in during bricklaying or before plastering. In practice, people often order their doors right at the start, and the doors then sit wrapped up in a half-finished house. If plastering happens in the meantime, the leaves can soak up moisture and twist as they dry out. You will have fewer worries if you arrange the door delivery for after the wet trades have finished.

The type of frame decides when it goes in and how the finished door looks. Both types have their place:

• Steel frame: it copes with knocks and damp, so it suits basements, plant rooms and busy hallways. It is built into the masonry and filled with mortar. If you ever want to replace it, you will have to break it out and repair the plaster around the opening.
• Lining frame: it wraps around the full thickness of the wall and matches the colour of the door leaf. It goes into the finished opening, held by expanding foam and spacers, and you can replace it later without damaging the wall. It is more sensitive to knocks and long-term damp, though.

Every lining frame is made for a certain range of wall thicknesses. So measure the wall including plaster and tiles. In a bathroom, tiling adds several centimetres to the wall, and you need to allow for that when you order. For bathrooms, it pays to choose a frame with a more moisture-resistant bottom edge or to seal it at floor level. Otherwise water from a wet floor can creep up into the chipboard core.

Internal doors are described by the width of the leaf. In much of continental Europe the usual widths are 60, 70, 80 and 90 cm, while in the UK and some other markets you will often see sizes such as 686, 762 or 838 mm. The structural opening for a lining frame is usually about 10 cm wider than the leaf. The manufacturer sets the height of the opening, always measured from the finished floor, not from the bare concrete. That is why the supplier will ask how high the whole floor will be, including the floor covering.

How do you know whether you need a left-hand or a right-hand door? This is where people get caught out, because the conventions differ between countries and manufacturers. In the common continental system, you look at the door from the side it opens towards, the side where you can see the hinges. If the hinges are on the left, it is a left-hand door. Other systems work the other way round. Ask the supplier which convention they use and check the drawing before you confirm the order. A door that opens the wrong way is a common complaint, even though the product itself is fine and the mistake happened when ordering.

Doors to the bathroom, WC and kitchen also help with ventilation. When an extractor fan or cooker hood is running, the air needs somewhere to come in from. A larger gap under the leaf, a ventilation grille or an undercut door solves this. If your home has a gas appliance that takes its air from the room, the air supply is a matter for a qualified, registered gas engineer, not the joiner. And if you ever smell gas, leave the property straight away and call the gas emergency line or 112 from outside.

The door from your flat to the shared corridor is not an ordinary internal door. It usually has to be fire-rated as set out in the building's fire safety design, for example EI 30 or EW 30 under the European classes, or FD30S in the UK, and it often needs a self-closer too. Fire doors are certified as a complete set: leaf, frame, ironmongery and the way they are fitted. If you replace only the leaf and keep the old frame, or swap a fire-rated handle for an ordinary one, you can make the whole assembly worthless as a fire door.

Before you start, talk to the building management or owners' association. They know what the building requires and how the corridor doors are meant to look. If the width of the opening changes or the work touches a load-bearing wall, it counts as a structural alteration. What kind of approval you need depends on local building regulations, so check directly with the local building authority rather than assuming a simple notice will do. Any work on a load-bearing wall needs to be assessed by a structural engineer.

Timber is hygroscopic, which means it takes moisture in from the air and gives it back again. Solid wood moves mostly across the grain. So stair treads, window boards and cladding must never be gripped tightly on every side, as the wood needs a little room. Timber for interiors usually has a moisture content of around 8 to 12%. In living spaces, aim to keep the relative humidity at roughly 40 to 60%.

Everyday doors and furniture also use wood-based boards and surface materials:

• Chipboard and MDF: they change size less than solid wood, but once they soak up water they swell and never go back to their original shape.
• Veneer: a thin layer of real wood. You can sand it, but only once, twice at most.
• Foil and CPL or HPL laminate: tough and easy to keep clean. Damage is hard to repair, though, and usually means replacing the whole part.

It is worth knowing exactly what you have been supplied with. A veneered door leaf can be refinished in a few years' time, a foil-wrapped one cannot.

A made-to-measure wardrobe is built from a survey of the finished room, so only after plastering and flooring. Walls, ceilings and floors are never perfectly square. That is why the carcasses stand on adjustable feet and the cover strips are scribed to fit on site. With sliding doors, the top track matters most: it has to be straight and firmly fixed to the ceiling. If you have a plasterboard ceiling, there must be a load-bearing profile or a timber noggin above it.

Is the wardrobe going against an external wall? Then it needs a ventilation gap behind the back panel and openings at the plinth and at the top. Without air moving, moisture condenses on the cold wall and mould grows behind the wardrobe. Owners usually only notice it when they pull the wardrobe out on moving day.

Wall-hung kitchen units and shelves rely on the right wall plug for the wall. Aerated concrete blocks, hollow bricks and plasterboard need special anchors, or a timber noggin that has to go in while the partition is being built. Before you drill, find out where the cables and pipes run. They usually follow installation zones near the ceiling, in corners and around windows and doors. Hard-wiring appliances, lighting under the units and new sockets are jobs for a qualified electrician, not for the joiner or for you.

Before you clad a concrete staircase in timber, measure whether every step has the same height. Even a one-centimetre difference feels like a trip underfoot. Make up differences underneath the tread, not by using timber of different thicknesses. To tell whether stairs will feel comfortable, use the step rule: twice the height of a step plus its depth should come to roughly 600 to 650 mm. The exact stair dimensions come from the design and your local building regulations.

Treads are bonded to the concrete with an elastic adhesive made for timber, or fixed mechanically. The surface underneath must be dry and level. Risers close the gap between treads, so the staircase looks more solid and small objects do not fall through. They do not add to the strength of the stairs, which comes from the supporting structure.

The choice of timber depends on how much wear the stairs will take. Softwoods such as spruce or pine cost less, but they dent quickly on stairs. For treads, people usually choose hardwoods such as oak or beech. Original solid timber stairs can be brought back by sanding and applying three coats of lacquer. With veneered treads, find out first how thick the veneer is, or you may sand right through it. Lacquer forms a hard film on the surface. Oil soaks into the wood and lets you repair just the damaged spot without sanding the whole tread. Whichever finish you choose, think about an anti-slip treatment as well.

Handrails and balustrades stop people from falling. Their height and the gaps allowed in the infill are set by local building regulations and the design. Handrail brackets must go into the solid material of the wall, not just into the plaster.

Tongue-and-groove boards and other timber cladding go onto battens. The battens even out an uneven wall and leave a ventilated gap behind the cladding. Vertical boards need horizontal battens, and horizontal boards need vertical ones. Leave an expansion gap at the floor and ceiling, then cover it with a trim. Concealed clips let the timber move. If you nail the boards straight through the face, they will crack sooner or later.

An internal window board slides under the window frame or up against its sill profile. It is bedded and packed underneath so that it does not bend when someone leans on it. It usually sticks out about 2 to 5 cm beyond the plaster. If there is a radiator under the window, the window board must not block the warm air rising from it. With a deep overhang, fit a ventilation grille into the board. Otherwise the window mists up and mould can appear in the corners.

If a door rubs on the frame or will not latch, you often do not need a new one, just an adjustment. On fire-rated entrance doors, though, replace ironmongery only with certified parts.

1. Find out what hinges the door has, pin hinges with an adjusting screw or concealed adjustable hinges, and look up the manufacturer's instructions for them.
2. Look at where the leaf rubs and how the gaps around it vary, and work out which way it needs to move.
3. Open the door and push a wedge under the bottom edge so that the leaf does not drop when you loosen the hinges.
4. Turn the adjusting screws a little at a time and check how the door closes after each change.
5. Check that the gaps between leaf and frame are even all round, usually a few millimetres according to the manufacturer.
6. To replace the handle, undo the screws on the backplates or roses and pull the handle out together with the spindle.
7. Measure the spindle, usually 8 mm on interior doors, and the spacing of the lock holes so that the new handle fits.
8. Fit the new handle, tighten the screws without overtightening them, and check that the handle springs back and the latch engages.

At handover, check how things work as well as how they look. It is easiest in daylight, with a spirit level in your hand:

• Frames stand plumb, sit flush with the wall and show no gaps between the lining and the plaster
• Doors do not swing open or shut on their own in any position
• Gaps around the leaf are even, and the gap above the finished floor matches the manufacturer's instructions or the ventilation needs
• Locks, handles and keys work, and the latch engages without pushing
• You have received documents confirming the fire rating of the complete entrance door assembly
• Stair treads are firm, do not creak and all have the same height
• The handrail is securely anchored and has no sharp edges
• Skirting boards hold tight to the wall and meet neatly in the corners
• Cabinets are level, and doors and drawers have even gaps
• Surfaces are free of scratches, adhesive marks and foam residue
• You have the care instructions, warranty documents and details of the surface finish