Choosing the correct size cornice is important to ensure the moulding looks balanced in proportion to the room and ceiling height.
Cornice is available in a wide range of sizes and designs. The correct size will usually depend on the dimensions of the room, the ceiling height and the level of decorative detail required.
This guide explains how cornice is measured and provides recommended cornice sizes to help you select the right profile for your space.
What Size Cornice Do I Need?
As a general rule, rooms with standard ceiling heights usually suit cornice with a drop and projection of between 80mm and 130mm. Larger rooms or properties with higher ceilings can accommodate considerably larger and more decorative cornice profiles.
The style of the cornice can also influence the size you choose.
- Plain or contemporary cornice profiles often work well in smaller rooms or where a subtle finish is required.
- Traditional Victorian or Edwardian cornice is generally more decorative and often works best in standard to larger rooms.
- Large decorative cornice is typically used in rooms with high ceilings, period properties or spaces where the cornice is intended to become a prominent architectural feature.
Understanding Cornice Drop and Projection
Cornice size is normally shown using two measurements:
Drop – the distance the cornice extends down the wall.
Projection – the distance the cornice extends across the ceiling.
For example, a cornice measuring 120mm drop × 120mm projection will extend approximately 120mm down the wall and 120mm across the ceiling.
Some cornice profiles have an equal drop and projection, while others extend further across either the wall or ceiling. It is therefore important to check both measurements before selecting a profile.
Cornice Size Guide by Room and Ceiling Height
The following table provides a general guide to selecting the correct cornice size based on typical room dimensions and ceiling heights.
| Room or Ceiling Type | Recommended Cornice Drop and Projection |
|---|---|
| Small rooms, hallways or cloakrooms | 60mm – 90mm |
| Standard bedrooms | 80mm – 120mm |
| Standard living rooms and dining rooms | 100mm – 150mm |
| Large rooms or open-plan spaces | 140mm – 200mm |
| High ceilings and period properties | 180mm and above |
These recommendations provide a general guide. The ideal cornice size will also depend on the proportions of the room, the cornice design and the overall style of the property.
Cornice Size Guide by Ceiling Height
Ceiling height is one of the most important factors when selecting cornice.
| Ceiling Height | Recommended Cornice Size |
| Up to 2.4 metres | 60mm – 100mm |
| 2.4 metres to 2.7 metres | 80mm – 130mm |
| 2.7 metres to 3 metres | 120mm – 170mm |
| 3 metres to 3.5 metres | 150mm – 220mm |
| Over 3.5 metres | 200mm and above |
A larger cornice may look impressive when viewed closely, but it can appear too heavy in a room with a low ceiling. Equally, a small cornice can become lost in a large room or on a high ceiling.
Common Plaster Cornice Sizes
The table below shows common plaster cornice sizes and the types of rooms in which they are typically used.
| Approximate Cornice Size | Suitable Room Type |
| 60mm – 80mm | Small rooms, hallways and low ceilings |
| 80mm – 110mm | Bedrooms, home offices and smaller reception rooms |
| 110mm – 150mm | Living rooms, dining rooms and standard period properties |
| 150mm – 200mm | Large reception rooms and higher ceilings |
| 200mm and above | Grand rooms, large period properties and very high ceilings |
Choosing Cornice for a Standard Ceiling Height
For a standard ceiling height of approximately 2.4 metres, a cornice with a drop and projection of around 80mm to 120mm will usually provide a balanced appearance.
Smaller profiles create a more subtle transition between the wall and ceiling, while profiles closer to 120mm provide a stronger and more traditional decorative finish.
In a larger room with the same ceiling height, it may be possible to use a slightly larger cornice. However, care should be taken to avoid reducing the apparent height of the room.
Choosing Cornice for High Ceilings
Rooms with ceilings above 3 metres can generally accommodate larger and more decorative cornice profiles.
Cornice with a drop or projection of 150mm to 220mm often works well in Victorian and Edwardian properties, particularly in large living rooms, dining rooms, entrance halls and reception rooms.
Very high ceilings may require cornice exceeding 200mm to ensure the profile remains visible and correctly proportioned when viewed from floor level.
Choosing the Right Cornice for Your Room
Choosing the correct cornice size helps create a balanced transition between the walls and ceiling.
Small rooms and standard ceiling heights usually suit cornice between 60mm and 120mm, while average living rooms and dining rooms often work well with profiles between 100mm and 150mm. Larger rooms, high ceilings and period properties will usually benefit from a larger cornice to prevent the moulding from appearing undersized.
When selecting a cornice, it is also important to consider:
- The height and dimensions of the room
- The depth of any existing skirting boards or wall mouldings
- The architectural period and style of the property
- The amount of decorative detail within the cornice
- Whether the cornice will be used for concealed LED lighting
- Any restrictions caused by windows, fitted furniture or door frames
A well-proportioned cornice will complement the room, frame the ceiling and provide a finished architectural detail without overwhelming the space.
Need Help Choosing a Cornice Size?
If you are unsure which cornice size is suitable, send us the dimensions of the room, ceiling height and photographs of the space.
Our team can recommend suitable plaster or lightweight cornice profiles based on the proportions and style of your property.