Installation of Plasterboard Partition/Furred Wall with Knauf Diamant Boards (Enhanced Acoustics/Hardness)

Both are high-hardness plasterboards. Compared with a standard board they are denser, with a tougher surface and a stronger core. The difference lies mainly in what each board is designed to do.

• Diamant is an all-round hard board. It suits rooms where you want better acoustics and a tougher wall, such as a bedroom, a child's room or an office.
• Habito is stronger still and is designed mainly for fixing things to the wall. According to the manufacturer, you can hang light and medium-weight items straight into the board without hunting for a stud. Check the exact load per fixing point in the manufacturer's technical data sheet.

If you already know the wall will carry kitchen units, a bookcase or heavier equipment, consider Habito. For a quieter, tougher partition without heavy loads, Diamant is usually enough.

A hard board alone will not work miracles. The result depends on the whole build-up, meaning all the layers working together.

• Metal frame made of perimeter tracks (often called U or UW profiles) and vertical studs (C or CW profiles). Studs usually sit at roughly 60 to 62.5 cm centres, depending on board width. For heavier loads or tiling they go closer together.
• Acoustic sealing tape under every profile that touches the floor, ceiling or side walls. It reduces the vibration passed into the surrounding structure.
• Mineral wool in the cavity. It absorbs sound that would otherwise bounce around an empty cavity like the inside of a drum.
• Lining in one or two layers on each side. Two layers improve sound insulation and strength a lot. The joints of the second layer are staggered against the first.

Why does weight help against noise? A heavier board vibrates less when sound hits it, so it passes less energy to the other side. That is why a double layer of hard board with insulation dampens voices or a TV noticeably better than a lightweight partition.

1. Set out the position of the partition, mark it on the floor and transfer it to the ceiling with a laser or plumb line.
2. Stick sealing tape to the tracks, fix them to the floor and ceiling, then fit the end studs against the walls.
3. Insert the studs at the specified spacing and fit reinforced door-frame profiles at any openings.
4. Run electrical cables or pipes through the cavity. Where heavy items will hang, add noggins or reinforcement if the system requires it for that load.
5. Board one side, fit mineral wool with no gaps and without squashing it, then board the other side.
6. With a double lining, fit the second layer with staggered joints.
7. Fit corner beads, fill the joints and screw heads according to the manufacturer's system, and seal the perimeter with a permanently flexible sealant.
8. Once dry, sand, prime and prepare the surface for painting.

If the partition hides a riser or services that will need attention later, plan an access panel from the start.

Hard boards are heavier than standard plasterboard and harder to cut. They also need screws made for this type of board. An ordinary screw often will not sink in properly or snaps. The work therefore takes longer, and two people are needed to handle the boards.

The job gets harder with:

• a high ceiling and an uneven ceiling or floor,
• a double lining and higher acoustic requirements,
• door openings, corners, sloping ceilings and junctions with windows,
• many cables, sockets and reinforcements in the wall,
• difficult access, for example carrying boards up several flights of stairs.

A level, dry room that is cleared and ready makes the work easier. So do a clear plan for services and an agreed list of where furniture will hang.

In a block of flats, speak to the building management or owners' association before you start. Whether a layout change needs a notification, an approval or nothing at all depends on local building regulations and the scope of work, so check with your local building authority. Wiring in the partition should be connected by a qualified electrician, as local rules usually require.

• Missing sealing tape, or a rigid connection to the ceiling and walls that lets sound through.
• A cavity without mineral wool, or wool with gaps, which loses much of the acoustic benefit.
• Studs spaced too far apart, so the wall flexes and the joints crack.
• Too few screws, heads left proud, or ordinary screws instead of screws for hard boards.
• Sockets placed back to back on both sides of the wall, which creates an acoustic hole.
• A rigid connection to a ceiling that may deflect. In that case a sliding head detail is used.
• Rushed jointing without enough drying time, which leads to hairline cracks.

A handy DIYer can manage a simple partition without a door in a room with a normal ceiling height. Expect heavier boards and more dust when cutting. Leave all electrical work to an electrician.

1. Check the manufacturer's system build-up and the specified screws for your chosen board.
2. Mark the position of the partition on the floor, walls and ceiling.
3. Stick on sealing tape and fix the tracks and end studs.
4. Fit the studs at the spacing given by the manufacturer and check them with a spirit level.
5. Board the first side. Cut boards with a plasterboard saw or a knife with spare blades, and wear a dust mask while cutting.
6. Fit mineral wool over the whole cavity with no gaps.
7. Board the second side, staggering the joints if you use two layers.
8. Fill the joints and screw heads, seal the perimeter with flexible sealant and let everything dry thoroughly.
9. Sand, prime and paint.

• The wall is plumb and flat, with no visible flex when you push on it
• A continuous bead of flexible sealant runs around the perimeter with no gaps
• Screw heads are sunk and filled
• Joints are smooth, without cracks, bubbles or lifting tape
• Corner beads protect the external corners and the edges are straight
• Any door opens freely and the frame is solid
• You have a drawing or photos of the services and reinforcement positions inside the wall
• Sockets and switches are connected by an electrician and are not back to back on both sides