Definition:
Gypsum ceiling also referred to as suspended drywall is a type of false ceiling used by interior designers to aesthetically cover services in the ceiling like electrical conduits, fire fighting pipes, air conditioning ducts etc.
Products available in the market:
Gypsum ceiling is made up of two things, 1. The galvanized iron (GI) framework 2. The Gypsum sheets fixed to the GI framework from below. Manufacturers produce Gypsum boards as well as GI sections for the framework. Accessories involved are jointing compound, jointing tape and self-tapping screws. The major manufacturers specified by interior designers in Mumbai, India are India Gypsum (now Saint Gobain) and La Farge
The sheets are available in 3 types:
1. Standard
2. Moisture resistant (Specified by architects and interior designers for washrooms and wet areas)
3. Fire resistant (Specified by architects and interior designers to prevent fire from
The min. thickness of gypsum board is 9.5mm and the size of boards is 8’0” x 4’0”
Installation process:
The GI frame is suspended from the ceiling using GI suspenders. Architects and interior designers specify appropriate GI sections and centre to centre distances between the grid as per manufacturer’s specifications. The boards are fixed to the GI frame using self-tapping screws (drywall screws).
Most important part of the installation process (This is going to make or break the finish of the ceiling):
1. Make a v groove at the joints between two sheets. Sheets come with this groove (like a shallow 2” wide niche) by default. But you have to make this groove or niche for boards that are cut to size. (see pic)
2. Apply a paste of jointing compound between the joints. (see pic)
3. Apply jointing tape over the joint just when the jointing compound is wet. (see pic)
4. Apply another layer of jointing compound immediately over the tape and level it off. (see pic)
Later when the joint dries you can sand the joints using sanding paper. If this process is not done correctly you will see a wavy and unfinished surface.
