To most people plasterboard is just the white sheet behind the paint. On a build it is a specification decision, and getting it wrong is costly: the wrong board in a bathroom fails early, the wrong board on a boundary wall fails certification and has to come off.
This guide covers the types of plasterboard you will actually meet on a job, in the order you will meet them. It is written by the team at MYT Buildings Solutions who fix and finish these boards on Adelaide sites daily, so the warnings below are the mistakes we are called in to fix.
The five main types of plasterboard
Almost every residential and commercial job uses some combination of five boards. They look broadly similar on a pallet, which is exactly why substitution mistakes happen so often.
| Board type | Typical thickness | Where it belongs |
|---|---|---|
| Standard | 10mm | General walls and ceilings in dry areas |
| Ceiling | 13mm | Ceilings, matched to batten or joist spacing |
| Moisture resistant | 10mm | Bathrooms, ensuites, laundries, behind sinks |
| Fire rated | 13mm and 16mm | Boundary walls, party walls, risers, shared garage walls |
| Acoustic | 13mm | Bedrooms, media rooms, intertenancy walls |
Standard plasterboard
The default sheet for general internal walls and ceilings in dry areas: bedrooms, living rooms, hallways and robes. Usually 10mm thick in 1200mm wide sheets, with lengths from 2400mm to 3600mm chosen to suit your ceiling height and minimise the number of joints a flusher has to hide.
Use it everywhere a wall has no special demand placed on it. It is the cheapest board per square metre and there is no benefit in upgrading where there is nothing to upgrade for. Sheet length selection matters more than most people realise: choosing a length that matches your ceiling height can eliminate a horizontal joint across an entire wall.
Ceiling plasterboard
Ceilings are a different engineering problem from walls: the sheet has to resist sagging under its own weight across the span between joists or battens, with insulation sitting on top of it. Ceiling board is manufactured for that, commonly 13mm, in longer sheets from 3000mm to 4200mm.
Moisture resistant plasterboard for wet areas
Usually recognisable by its green face. The core and liners are treated to resist moisture absorption, which makes it the correct board for bathrooms, ensuites, laundries, powder rooms and the wall behind a kitchen sink.
One clarification that matters enormously: moisture resistant board is not waterproofing. Wet areas still require a compliant waterproofing membrane installed over the substrate in line with the National Construction Code. The board resists incidental moisture and humidity, the membrane keeps water out of the structure. You need both, and a failure of either shows up as a very expensive problem two years later.
Fire rated plasterboard and compliance
Fire rated board has a denser core with additives that hold it together longer under fire, buying time for the wall assembly to maintain its rating. It comes in 13mm and 16mm, and where it is specified it is not a preference, it is a legal requirement.
You will find it on boundary and party walls, service risers, corridors in multi residential buildings, garage walls sharing a boundary with the house, and anywhere your certifier has nominated a fire resistance level.
The critical point that catches people out is that fire ratings apply to a tested system, not to a sheet. The FRL comes from the specific combination of board, stud, insulation, fixings and jointing used in the original test. Substituting any component, including the screws, can invalidate the rating. If you want to understand how these assemblies are verified, the ABCB publishes a fire safety verification method handbook that explains the framework.
Acoustic plasterboard for quieter rooms
Denser and heavier than standard board, engineered to reduce sound transmission through the wall. Common in 13mm.
Worth specifying around bedrooms, home offices, media rooms, bathrooms shared with living spaces, and any intertenancy wall in a townhouse or apartment. It works best combined with acoustic insulation in the cavity and acoustic sealant at the perimeter. The board alone will disappoint if the wall is full of gaps, which is why we treat acoustic walls as a system rather than a board upgrade.
Which plasterboard type for each room
| Room | Recommended board |
|---|---|
| Bedrooms and living areas | Standard 10mm, acoustic if noise separation matters |
| Ceilings | Ceiling board 13mm at correct batten spacing |
| Bathroom, ensuite, laundry | Moisture resistant, plus compliant waterproofing |
| Kitchen splashback zone | Moisture resistant behind sink and wet zones |
| Garage wall to house | Fire rated to the specified FRL |
| Boundary or party wall | Fire rated, often with acoustic requirements as well |
| Media room or home office | Acoustic board with acoustic batts and sealant |
| Apartment intertenancy wall | Fire and acoustic rated tested system |
Our full Plasterboards range covers all five board types plus the compounds, tapes, screws and cornice that complete the system, and we supply either on its own or as part of a supply and installation package.
How to choose between the types of plasterboard
Work through three questions for every wall and ceiling on your plan, in this order. It takes minutes and it prevents almost every specification error we see.
- 1Is it compliance driven? If a fire resistance level or an acoustic rating is nominated for that wall, the answer is decided for you. Install the tested system exactly as specified, with no substitutions of board, framing, insulation or fixings.
- 2Is moisture present? Bathrooms, ensuites, laundries and the zone behind a kitchen sink call for moisture resistant board, with waterproofing on top where the code requires it.
- 3Will anyone be annoyed by noise through it? Bedrooms, media rooms and home offices benefit from acoustic board plus acoustic batts. This is the question people forget, and the one that generates the most regret after handover.
If the answer to all three is no, standard board is the correct and most economical choice. Upgrading a hallway wall achieves nothing except cost.
Costly mistakes when specifying types of plasterboard
These are the errors that generate call backs, and every one of them is cheaper to avoid than to remedy.
- Substituting a fire rated board for a cheaper equivalent. The rating belongs to the tested system, not the sheet. A substitution can invalidate certification and the wall may have to come off.
- Using standard board in a laundry. It is technically a dry area on the plan, but the reality is a humid room with a washing machine in it. Moisture resistant board is a small upgrade that avoids a premature failure.
- Ordering short sheets to save money. Extra joints mean more flushing labour and more places for a visible line to appear later. Sheet length should suit the wall, not the invoice.
- Treating one side of an acoustic wall. Sound passes through both faces. Boarding one side with acoustic sheet and the other with standard board wastes most of the upgrade.
- Forgetting the cornice and finish level. These are specified far too late in most jobs, and by then the budget has already been allocated elsewhere.
Finish levels matter as much as the board type
The sheet is only half the outcome. The finish level determines what the wall actually looks like once painted, and it is where budget quotes quietly differ from good ones.
- Level 4 is the standard finish for most painted walls and ceilings, suitable for typical domestic lighting and matt paint.
- Level 5 adds a full skim coat over the entire surface, and it is what you want on feature walls, in raking natural light, or under gloss and low sheen paints where every joint would otherwise telegraph through.
If you have ever walked past a wall at sunset and seen every joint and screw head appear, you have seen a Level 4 finish in a location that needed Level 5. It is not a defect in the work, it is a specification decision that was made without anyone explaining the consequence.
Frequently asked questions
Moisture resistant plasterboard, commonly identified by its green face. It resists humidity and incidental moisture, but it is not a substitute for waterproofing. A compliant waterproofing membrane is still required in wet areas under the National Construction Code.
