MF Ceiling Components Explained: MF5, MF6A, MF7 and MF9

An MF ceiling is a suspended plasterboard ceiling fixed to a lightweight galvanised steel grid. It is the standard way to drop a ceiling below a concrete slab or an uneven timber floor, hide services, or get a flat, level ceiling where the structure above is anything but. If you have been handed a spec that mentions MF5, MF6A, MF7 and MF9 and are not sure what goes where, this guide explains each part and how the system goes together.

The components at a glance

Part	What it is	What it does
MF6A	Perimeter channel	Fixed around the walls at ceiling level. Supports the edges of the grid and sets the ceiling line.
MF7	Primary channel	The main bars of the grid, hung from the soffit on hangers.
Hangers	Angle or strap hangers	Suspend the MF7 from the structure above and set the drop.
MF5	Furring (ceiling) section	Runs at right angles under the MF7. The plasterboard is screwed to it.
MF9	Connecting clip	Clips the MF5 to the MF7 at every crossing.

We stock MF6A perimeter channel, MF7 primary channel and MF5 furring sections from Hadley and Alpha, all sold in packs of 10 × 3.6m lengths, plus MF9 clips by the box.

Typical spacings

Spacings depend on the system, the board and any fire or acoustic specification, so always work from the manufacturer's guidance. As a guide, British Gypsum's published guidance for a standard MF ceiling is:

• MF7 primary channels at no more than 1200mm centres, spanning the shorter side of the room, with joins overlapped by 150mm.
• Hangers at no more than 1200mm centres along each MF7, giving a 1200 × 1200mm suspension grid.
• MF5 furring sections at a maximum of 450mm centres for 12.5mm and 15mm board. Closer 400mm centres let every end of a 2400mm board land on a section.
• MF9 clips at every point where an MF5 crosses an MF7.
• MF6A perimeter channel fixed to the walls at 600mm centres.

How an MF ceiling goes together

1. Set out the ceiling line. Mark a level line around the room at the height of the finished ceiling, less the board thickness.
2. Fix the perimeter channel. Fix MF6A to the walls along the line.
3. Fix the hangers. Fix hangers to the soffit on the 1200mm grid, cut to the drop.
4. Hang the primary channels. Fix the MF7 to the hangers and level the grid.
5. Clip on the furring sections. Fix MF5 at right angles below the MF7 using MF9 clips, at your chosen centres.
6. Board the ceiling. Fix the plasterboard with its long edges at right angles to the MF5, stagger the end joints, and screw at 230mm maximum centres, reducing to 150mm at board ends. For a single layer of 12.5mm board, a 25mm drywall screw gives the recommended 10mm penetration into the steel.

Plan for light fittings, access panels and anything heavy that will hang from the ceiling. These usually need extra MF5 sections or supplementary framing.

Fire, acoustic and insulation

If the ceiling has to achieve fire resistance or sound insulation, build it exactly to a tested system specification, including the board type, number of layers and screw centres. Acoustic hangers are used in some systems to isolate the ceiling from the structure above. Adding mineral wool above the ceiling adds weight, which is one reason to use closer MF5 centres. Our guide to acoustic insulation explains the basics.

Work out your materials in a minute

Our free MF ceiling calculator takes your room length, width and drop and works out the MF7, MF5, MF6A, hangers, clips, boards and screws, following British Gypsum's guidance. It rounds metal up to whole packs, prices everything live and adds the list to your basket in one click. For irregular rooms, split the room into rectangles or send us your drawings.

Frequently asked questions

Should I use 450mm or 400mm MF5 centres?

450mm is the normal maximum for 12.5mm and 15mm plasterboard. Use 400mm if you want every board end to land on a section, if you are adding insulation above, or if your specification asks for it.

Can I mix Hadley and Alpha sections?

It is best to use one manufacturer's sections throughout so the profiles and clips match. The calculator lets you choose either range.

Order your MF ceiling system

Browse the full MF ceiling system range. Prices are shown ex VAT, and we deliver across mainland England and Wales (see delivery information). Call us on 03330 908479, email sales@insulationwarehousedirect.co.uk, or order online.

Sources: British Gypsum White Book, GypCeiling MF guidance and Site Book good practice guide; Hadley MF section datasheets. Always follow the system manufacturer's current specification.