Material Quality Standards
1. Base Material Properties: Paper-faced gypsum boards must comply with the GB/T 9775 national standard, featuring a smooth surface free from powdering or damage. Aluminum panels for integrated kitchen and bathroom ceilings must have a thickness of at least 0.6 mm and be free from oxidation, deformation, or scratches. Light-gauge steel furring channels must have a thickness of ≥0.6 mm; wooden furring strips must be kiln-dried and free from rot, insect damage, or warping. Adhesives and coatings used in conjunction must meet environmental protection requirements.
2. Environmental Indicators: Formaldehyde emissions from ceiling panels must meet the E0 or ENF grade standards. VOC content must comply with the regulations set forth in GB 50325, "Code for Indoor Environmental Pollution Control of Civil Building Engineering," and the materials must be free from distinct, pungent odors.
Installation and Construction Standards
1. Furring/Grid Installation: The spacing between main channels must be kept within 1,200 mm, and the spacing between furring channels must be ≤400 mm (for gypsum board ceilings); hanger spacing must be ≤900 mm. L-shaped reinforcement is required at ceiling corners to prevent cracking, and the installed framework must be secure with no looseness or wobbling.
2. Panel Installation: When securing gypsum boards to the framework, self-tapping screws should be spaced 150–200 mm apart; screw heads must be countersunk and treated against rust, and expansion gaps of 3–5 mm must be left between panels. For integrated ceiling panels, joints must be flush and seams uniform in width, with no warping or looseness.
3. Detailing and Finishing: Internal and external corners must be straight and plumb; edge trims must fit tightly against walls and the ceiling, with no visible gaps or curling edges.
Safety and Performance Standards
1. Load-bearing capacity: Ceilings in standard residential areas must support a load of at least 3 kg/m²; integrated ceilings in kitchens and bathrooms must support the weight of auxiliary equipment such as bathroom heaters and light fixtures, with all mounting points remaining secure and free from loosening or detachment.
2. Fire and moisture resistance: The fire resistance rating of gypsum board ceilings must comply with relevant building fire safety regulations; metal furring channels and panels for kitchen and bathroom ceilings must be rust- and moisture-resistant to prevent corrosion or deformation during long-term use.
3. Electrical safety: Electrical wiring installed within the ceiling void must be enclosed in PVC conduit; wiring connections must be standardized and well-insulated; designated locations for electrical appliances must be accurately positioned, with no exposed live parts.
