Renovating a Queenslander: Raising, Restumping and Building In Underneath Without Losing the Character, or the Ceiling Height

Raising a Queenslander and building in underneath is one of the most common ways to add space to an older timber home without giving up the yard. It's also where character rules, ceiling heights and a house that has been settling on its stumps for decades all meet. Get the order wrong and you find out on site that the house needed to go higher, or that the street front needed council approval.

This guide covers renovating a Queenslander home by raising, restumping and building in under: what to check in the planning rules, the standard ceiling height in Queensland for the new rooms, how far the house has to go up, what happens to the house during the lift, and what to measure before anyone designs. It's written for owners of older timber homes across South East Queensland.

What makes renovating a Queenslander different

A Queenslander is a timber-framed house on stumps, often with VJ board walls, a tin roof and verandahs, built to let air move underneath. That construction is what makes it easy to lift, and what makes it sensitive to being lifted.

• Timber that has moved. Floors fall, walls are out of plumb and doors have been planed to fit. The house you're renovating isn't the one on any old drawing.
• Stumps and bearers. The whole house sits on a grid of stumps and bearers. Its condition, spacing and direction decide what can be removed or opened up.
• Character rules. Many older houses are covered by a character or heritage overlay that controls what can change, especially at the front.
• Hidden materials. Houses built before 1990 may contain asbestos in eaves, wet areas, old flooring and cladding.

Character overlays: check before you brief a designer

Before any design work, look up your property in your council's planning scheme. In Brisbane, the traditional building character overlay applies to many houses built in 1946 or earlier, and some extensions and renovations to those houses need planning approval as well as building approval. Brisbane's rules say raising a house in the overlay doesn't need planning approval if the new height doesn't exceed 9.5 m, and enclosing under an existing house can be minor work, but changes to the street front, demolition and larger extensions are assessed.

Other councils have their own character and heritage rules, and a house on a heritage register has more. The rules change, so check your council's current planning scheme, or ask a town planner, before you commit to a design.

Building in under: the ceiling height you need

The standard ceiling height in Queensland comes from the National Construction Code: at least 2.4 m in habitable rooms such as living areas and bedrooms, and 2.1 m in kitchens, bathrooms, laundries and corridors. Building in under means fitting those heights between the new floor and the underside of the house above.

Three things sit inside that gap besides the room itself:

• The ceiling and services zone. The new ceiling lining, battens, and any pipes or ducts run under the bearers. Allow about 0.1 m if you're not sure.
• The new floor build-up. A new slab usually sits at least 150 mm above the finished ground. Your designer confirms the level.
• The real clearance. Measure from the ground, or where the new slab will sit, to the underside of the lowest bearer, not to the floorboards.

For a bedroom with 2.1 m of clearance now, that's roughly 2.4 m plus 0.1 m plus 0.15 m, or about 2.65 m needed: a raise of around 0.55 m. Enter your own numbers in the calculator below to see roughly how far the house would need to rise, the new ridge height against your council's limit, and what the raise sets off. It's indicative only; your designer, engineer and certifier set the real levels.

Raising and restumping: what happens to the house

A house raise is planned by an engineer, approved by a building certifier and carried out by a licensed house-raising contractor. The house is jacked up off its stumps, held on temporary supports, then set down on new stumps or posts, usually steel or concrete, at the new height. Restumping on its own follows the same steps without the extra height.

Everything attached to the house has to follow it: stairs, downpipes, plumbing, power, gas and the meter box. And because the frame moves, plaster and VJ boards can crack, doors can bind and windows can stick, even on a well-run job.

That's why the condition of the house before it moves matters. A dated record of every room before the lift answers the question that comes up after it: was that crack already there? It helps you and the house-raising contractor equally.

Asbestos, termites and what's under the floor

If the house was built before 1990, have it tested for asbestos before anything is cut, drilled or sanded, including eaves, wet-area linings, old vinyl and fibre-cement sheeting. Removal of more than a small amount needs a licensed removalist.

Check the stumps and bearers for rot, lean and termite damage before design, because the repair plan affects the raise. Note the pipes, cables and gas lines running under the floor too: the new rooms below will have to work around them or move them. Before You Cut has a checklist for walls, floors and the ground.

Measure the house for the design

Your designer needs the house as it stands: floor levels that fall, the stump grid and bearer directions, existing ceiling heights, and the clearance underneath. Old plans rarely show any of it accurately.

A 3D capture of the house, the subfloor and the roof space gives your designer and engineer measurements, levels and framing directions to work from before concept design starts, and the same capture is a dated record of the house before the lift. It's an architectural-grade record for design, not a survey, so a registered surveyor still sets boundaries and levels tied to a survey datum. The scan-to-BIM brief template sets out what to ask for, and our extension guide covers the approvals and stages that follow.

Renovating a Queenslander: FAQs