Gypsum Plaster Board
Types and Durability
| Description
Gypsum plaster board |
Expected Lifespan
(Years) |
Adjustment Factors |
| Gypsum board to BS 1230: Part 1, Type 3 (moisture resistant) | 30 | Routine access to ceiling void (more than twice/ year: -30% years
Excessive exposure to steam and moisture or under category ‘high humidity‘ to BS8290:Part 2: – 15% years Near overhead pipe: – 10% years. Test certificate from approved local testing authority : +15% years |
| Gypsum board to BS 1230: Part 1, Type 1, 2, 4 or 5 | 25 | |
| Gypsum board not to BS 1230: Part 1 or less than above specification | < 25 |
In case of 2 or more conditions of adjustment factor occur, the percentage of year shall be added.
Classification to BS 1230: Part 1: 1985
| Type | Description | Use |
| 1 | Gypsum wall board | Linings to walls, ceilings and partitions to receive decoration |
| 2 | Gypsum base wall board | Linings to walls, ceilings and partitions to receive veneer finishes |
| 3 | Gypsum moisture resistant wallboard | Lining where there is a risk of limited exposure of the board to moisture |
| 4 | Gypsum moisture repellent wallboard | Lining where there is a risk of limited exposure to moisture on the surface of the board. Comes with moisture resistant paper. |
| 5 | Gypsum wallboard F | Lining, as in type 1, but where improved fire protection performance required. |
| 6 | Gypsum baseboard | Linings to walls, ceilings and partitions, to receive a gypsum plaster |
| 7 | Gypsum baseboard F | Linings as in type 6 but where improved fire protection performance is required. |
Type 3 is the one recommended to be used as wet area ceiling.
Note: Certain types of plasterboard are not suitable for damp or humid environments. Reference should be made to manufacturer guide.
BS 8290 provides useful complementary information to this work section:
- Part 1 deals with design issues generally.
- Part 2 specifies materials, manufacturing tolerances and strength requirements for suspension grids.
- Part 3 deals with installation issues.
Other sources of information include the Specialist Ceilings and Interiors Association (SCIA) guides and Health Technical Memorandum 60.
Some non-metal materials are susceptible to dimensional changes and distortions caused by exposure to inappropriate environmental conditions either before or after installation.
BS 8290:Part 2 specifies the method for measuring the manufacturing tolerances (dimensional accuracy, squareness and flatness) of tiles, panels, etc. and includes for conditioning under the following environments:
- Normal: Relative humidity 65 ± 5% at 25 ± 2°C for 36 hours.
- High humidity: Relative humidity 90 ± 5% at 25 ± 2°C for 24 hours.