Gyproc GI Intermediate Section

• Manufacturer: Gyproc (Saint-Gobain)
• Product: GI Intermediate Channel — the primary supporting member of a false ceiling grid
• Function: Suspended from the slab, it carries the ceiling sections beneath it
• Dimensions: 15 x 45 x 15 x 3660 mm
• Length: 3660 mm (12 feet) — the same length as the Gyproc ceiling section
• Material: GI — galvanised steel, for a humid ceiling void
• Knurled surface so screws bite instead of skating
• Please note: Different from a ceiling section — see below

Gyproc GI Intermediate Channel is the primary supporting member of a suspended plasterboard ceiling — the channel that hangs from the structural slab and carries the ceiling sections beneath it, in a 3660 mm (12 foot) length.

It sits at the top of the load path, and the order runs like this: the slab carries the hangers, the hangers carry the intermediate channels, the intermediate channels carry the ceiling sections running perpendicular beneath them, and the ceiling sections carry the plasterboard. Everything above the board is there to hold the board flat and still.

One thing surprises people: the intermediate channel is narrower than the ceiling section it supports — a 45 mm web against 80 mm. It still carries the load, because the two are shaped for different jobs. The intermediate channel is a deep, narrow channel, and depth is what resists bending along a span. The ceiling section is wide and flat because its job is to present a face for the board, not to span distance. Judge them by shape rather than by width.

GI — galvanised steel — is specified throughout a ceiling grid for the same reason: a ceiling void is humid, unventilated and never inspected, and plain steel corrodes there for years before anything shows. The knurled surface gives screws something to bite into rather than skating across smooth galvanised steel.

Technical Specifications

Applications

1) What is the difference between an intermediate channel and a ceiling section?

They do opposite halves of the job and are not interchangeable. The intermediate channel supports — it hangs from the slab and carries the load. The ceiling section is what the plasterboard screws into. They run at right angles to each other, and a grid needs both. Mixing the two up is the commonest ordering error in drywall work.

2) Why is the primary member narrower than the one it supports?

Because they are shaped for different jobs. The intermediate channel is a deep, narrow channel, and depth is what resists bending along a span. The ceiling section is wide and flat because its job is to present a face for the board, not to span distance. Judge a section by its shape and depth rather than its width.

3) How do the channels and sections join together?

With connecting clips, which are a separate item. The clip holds the ceiling section to the underside of the intermediate channel where they cross. Without clips the two main components of your grid cannot be assembled to each other, so include them in the order.

4) How far apart should the channels be spaced?

Follow the spacing specified for your ceiling system, which depends on the board weight, the span and the hanger spacing. It is not a rule-of-thumb decision. Spacing channels wider saves material up front and is precisely what causes a ceiling to sag into shallow waves that become obvious under raking light — long after the boards are up and painted.

5) Is it the same length as the ceiling section?

Yes — both are 3660 mm (12 feet), which makes ordering and cutting simpler since you are working to one length across the grid.

1. Return within 24 hours of delivery for:
   • Damaged or defective product
   • Wrong or missing item
2. Product cannot be returned once installed or used
3. Refer to Refund Policy for complete details

Please check the channels for bends or transit damage on delivery — a bent primary member transfers its bend into the finished ceiling.