If you’re planning, or already have, a double-height extension or a room with unused roof space above it, then a mezzanine level – think home office, den or extra bedroom – could be a smart way to make the most of it while still enjoying the benefits of an airy room with a high ceiling.

Here, three building and architecture experts share their knowledge on which kinds of spaces are suitable and how best to plan the project.

Know your measurements

Not every space suits a mezzanine, so you’ll need to measure carefully. “Generally, mezzanine levels are located either within the roof space or in a room with oversized head height,” James Hood says.

“As a rule of thumb, you’ll need a minimum of 2.2m under the mezzanine platform, plus a floor thickness of 250mm, and a minimum of 1.6m to 1.8m to the top of the mezzanine itself,” he says.

When it comes to regulations, Michael Schienke explains: “No Planning Permission is needed for a mezzanine, unless you intend to extend your property externally.”

However, any work must adhere to Building Regulations. “It’s important to check with your designer, architect, engineer or local building control department to ensure the upper mezzanine level doesn’t fall outside of Building Regulations,” James says. “Usually, they’re classed as uninhabitable spaces and don’t have the same restrictions as a normal room.”

Consider what lies beneath

A mezzanine normally works best above a living area that doesn’t require a high ceiling or much daylight, such as a kitchen or bathroom, according to Stephen Fletcher. “Then the upper area should be something like an occasional bedroom, study or library,” he says.

“Mezzanines also work best when they only occupy one part of a grand space, so a double-height element remains and dominates,” he adds.

“When designing the structural calculations for the mezzanine level, it’s important to consider what the space will be used for,” James says. “Elements such as a large piano or bookshelf might need an increase in beam size. If the mezzanine is to cantilever out of a wall, then the structural design is critical from the start of the

Raise your roof

“The best mezzanines are created in the roof space,” Michael says. “Imagine partially removing your first-floor ceiling, then adding a circular staircase to the next level up from your first floor bedroom.

“You can then add rooflights into the roof slope, which will create views from the mezzanine and add light to both levels. This also gives you unique views from the mezzanine to the outside.”

Keep kids in mind

Mezzanines can be a brilliant option in children’s rooms, Michael suggests. “Give them great stairs up onto a private and fun higher level, with railings, of course, then add beanbags or other low-level chairs,” he says.

As well as adding a sense of adventure and a place to hide away, a mezzanine also makes practical sense for kids. “They can make the upstairs level into a space for playing while keeping the lower level where they sleep much tidier,” Michael says.

Plan as early as possible

If you can, James advises, think about your mezzanine at the start of your design process. “They often affect the general structural design,” he says.

“For a new build, the platform level will need to be integrated into the overall structural design of the building,” he says. “For a renovation project, new structural beams may be required, so this will need planning early in the process to avoid costs spiralling.”

Build in good access

“The most important thing to consider is whether to go for a full staircase or a ladder,” James says.

“Consider whether you want something interesting and sculptural or discreet and out of the way,” Stephen says. “Your staircase might also be integrated into a joinery unit that includes bookshelves.

“Don’t forget to assess the floor area your staircase will occupy,” he adds. “Spiral designs have a more compact footprint.”

James says, “A balustrade or guard rail is usually required, as a mezzanine area is open to the space below. Materials can vary; traditional timber, metal, glass, or a combination can all be used.”

“The balustrade should be high and sturdy enough to provide a sense of security and safety,” Stephen says.

Sneak in a study

In a bedroom with a high ceiling, a mezzanine can make a great home office.

“If your master bedroom needs space for a desk, but you don’t want it to be the first thing you see when you wake up, assess whether you can create a mezzanine,” Michael says. “Add comfortable stairs up to a ‘room within a room’, where you can have a more private area just for yourself.”