Suspended plasterboard ceilings in Sydney

No, and it is the most common mix up on this subject. An office ceiling is usually a demountable grid holding mineral fibre or vinyl faced tiles that lift out for access, and you can see the grid lines from the floor. What we install is a plasterboard ceiling hung on a concealed steel grid: it is jointed, set and painted like any other ceiling, and when it is done you cannot tell it is suspended. Most of the prices and products that come up when you search this phrase are for the tile version.

We price these per job rather than per square metre, because the grid is the work and the grid depends on the room. What moves it is the area, the height you are dropping to, what the hangers can be fixed to above, whether the ceiling is flat or raked, how many services are going into it, and how many control joints a large area needs. The per square metre figures that come up in search results are almost all for tile grid systems, which is a different product. Send dimensions and we will price the real thing.

Three real ones. You lose ceiling height, which is fine if you were lowering the ceiling on purpose and a genuine cost if you were not. It is more expensive than fixing board straight to the joists, because you are buying and installing a steel grid first. And anything that needs to change above it later means opening the ceiling, so services have to be thought about properly before it closes rather than afterwards.

No, it costs more, and where a direct fixed ceiling will do the job we will tell you to do that instead. It earns its cost in specific situations: where there is a concrete slab overhead, where the existing structure is uneven or not at usable centres, where services have to be concealed, or where you want the ceiling to move independently of the walls. Outside those, the simpler ceiling is the better answer.

That depends on what has to fit above it rather than on the ceiling itself. The grid and the board account for relatively little; the drop is usually set by the deepest thing going through the space, which on a retrofit is normally the air conditioning ducting. That is why we ask about services before setting a height, and it is why the answer is a number we work out with you rather than one we can quote in advance.

Yes, and that is often the whole reason for having one. The important part is that they are set out before the board goes up, not cut in afterwards. Cutting into a finished ceiling risks the acoustic or fire performance it was built to achieve, which matters particularly in apartments, and it means patching a ceiling that was flat. Give us the lighting plan and the ducting layout at the start and all of it gets planned into the grid.

Some, but there is a limit and it is lower than people expect. The ceiling framing is rated to carry 5 kilograms per square metre of insulation, and loading past that will put a slow sag into a ceiling that was perfectly flat when it was finished. If you are planning to insulate, or thinking of adding more later, tell us at the quote stage so the ceiling is built for it.

It is less prone to it, provided the perimeter is done properly. A suspended ceiling is deliberately isolated from the walls so that it floats as one plane and the building can move around it, which is exactly why it does not need the back-blocking a directly fixed ceiling requires. The catch is that this only works while that isolation is real. A suspended ceiling screwed hard to the walls at the edges will crack along that line like any other ceiling, and there is no finishing technique that fixes it afterwards.