What is a skirting board?

A skirting board (also called a baseboard in North America) is a length of timber, MDF, or PVC moulding fixed horizontally to the bottom of an internal wall at floor level. It serves three functions: it conceals the junction between the wall plaster or plasterboard and the floor, which is rarely clean enough to be left exposed; it protects the lower part of the wall plaster from kicks, vacuum cleaners, and furniture; and it provides a decorative transition between the wall and floor. Skirting boards are almost universal in UK domestic interiors.

What are the standard skirting board sizes?

Standard skirting board heights range from 70mm (minimal, modern) through 95mm and 119mm (common in most post-war housing) to 145mm and 170mm (for period-appropriate detailing in Victorian and Edwardian properties). Thickness is typically 15-18mm for MDF and 18-25mm for solid timber. Common profiles include: ogee (a traditional S-curve moulding), torus (a semicircular top edge), chamfered (a flat face with a stepped chamfer at the top), and plain square edge (for contemporary interiors). Heritage properties may have skirtings of 200mm or taller.

How are skirting boards fixed?

Skirting boards are fixed by nailing into timber stud framing (masonry nails or lost-head oval nails), by screwing and plugging into masonry walls, or by adhesive using a strong construction adhesive applied in a wavy bead to the back of the board. Modern practice increasingly uses adhesive only, as it avoids surface holes and works on any substrate. Internal corners are fitted with mitre joints or with a coped joint (one board cut square and butted into the corner, the second board coped to fit over the profile of the first). External corners are always mitred at 45 degrees.

What is the best material for skirting boards?

MDF (medium density fibreboard) is by far the most common material - it is stable, takes paint well, is available in all standard profiles, and is significantly cheaper than softwood. Softwood (typically redwood or whitewood pine) is used for period properties and where skirting will be stained or varnished (MDF cannot be stained). Hardwood (oak, tulipwood) is used for premium natural timber finishes. PVC skirting is used in wet areas (bathrooms, kitchens) and commercial settings where moisture resistance is needed. All timber skirting in contact with masonry walls needs to be kept off damp masonry with a DPC or sealant.

Finishes noun

Skirting Board

/ ˈskɜːtɪŋ bɔːd /

Also known as: skirting, baseboard, base moulding, floor trim

Definition

A skirting board is a length of timber, MDF, or PVC moulding fixed horizontally at the base of an internal wall to conceal the junction between the wall finish and the floor, protect the plasterwork from scuffs and knocks, and provide a decorative detail. Standard heights range from 70mm (slim, contemporary) to 170mm or taller (for period-appropriate interiors). Common profiles include ogee, torus, chamfered, and square edge.

In practice

MDF skirting (18-25mm thick) is the standard choice for painted interiors - it is dimensionally stable, machines to crisp profiles, and takes gloss or satinwood paint well. Solid softwood is used where the finish is to be clear-varnished or where a period repair requires matching existing timber. Skirting is fixed by nailing to timber studs, screwing and plugging to masonry walls, or adhesive bonding (which avoids surface nail holes). All joints between lengths are scribed (internal corners) or mitred at 45 degrees (external corners) to produce tight, crack-resistant joints.

When fitting skirting to a dot-and-dab plasterboarded wall, care is needed to avoid pushing the board back behind the dabs and distorting the face. A thin packing strip of the same thickness as the dabs (typically 3-5mm) may be needed to hold the skirting plumb. The gap between the bottom of the skirting and the floor finish is typically filled with a flexible decorator's caulk rather than mastic, allowing for floor movement without visible cracking. Skirting boards fitted before the floor covering are set at finished floor height to allow the floor finish to slip underneath.

Building Regulations

Fire (Part B)Timber skirting acceptable on walls up to 18m in most settings

Moisture (Part C)Timber skirting must not bridge DPC level at external walls

Thermal (Part L)Skirting over insulated wall lining must not bridge the insulation

Skirting boards are not themselves subject to Building Regulations approval, but their installation must not compromise the performance of the systems they sit against. Timber skirting must not be fixed through a DPC, be fixed to damp masonry below DPC level, or bridge a thermal break between wall insulation and the floor. In fire-rated compartment walls, intumescent strips or acoustic sealant behind the skirting maintain the fire and acoustic integrity of the wall at the floor junction.

Full Building Regulations guidance

Skirting Board

Just so you know...