Maintenance of PTFE/PVC membrane buildings

I. Maintenance of PTFE Membrane Structures

1. Cleaning

Frequency:
PTFE membrane surfaces have a contact angle >110°, exhibiting superhydrophobic properties. Rainwater can remove most dust. In lightly polluted areas (e.g., suburban regions), professional cleaning is required every 5-10 years. In industrial zones or areas prone to sandstorms, the cleaning interval may be reduced to 3-5 years.

Methods:

• Use high-pressure water jets (pressure ≤50 bar) with neutral cleaning agents (e.g., fluorocarbon surfactants with pH=7).
• Avoid scratching the surface.

2. Inspection

Inspection Cycle:

• Conduct a comprehensive inspection every 2-3 years, focusing on connection points (e.g., steel cables, anchors) and membrane surface damage.

Repair Costs:

• Localized damage: Repair using a heat gun (requires professional equipment) for spot fixes.
• Steel cable slack: Adjust pre-tension.

3. Replacement

Lifespan:

• PTFE membranes have a design lifespan of 25-30 years. In practice, only localized damaged areas (e.g., large tears caused by falling objects or extreme weather) need replacement.

Replacement Frequency:

• Approximately 5% of the membrane surface area is replaced every 10 years.

II. Maintenance of PVC Membrane Structures

1. Cleaning

Frequency:

• PVC membrane surfaces have high roughness (Ra >0.5μm), making them prone to dust accumulation and microbial growth (e.g., algae, mold). In heavily polluted areas, cleaning is required every 1-2 years; in cleaner areas, this can be extended to 3 years.

Methods:

• Use high-pressure water jets (pressure ≤30 bar) with alkaline cleaning agents (e.g., sodium carbonate solution with pH=10).
• Ensure thorough rinsing to avoid residue.

2. Coating Protection

Frequency:

• After each cleaning, reapply a fluorocarbon protective coating (e.g., PVDF coating) to delay UV aging and microbial adhesion.

3. Inspection and Repair Costs

Inspection Cycle:

• Inspect annually, focusing on membrane surface cracks, plasticizer migration (surface stickiness), and corrosion at connection points.

Repair Costs:

• Localized cracks: Repair using hot-air welding.
• Plasticizer migration: Requires partial replacement of the membrane material.
• Steel cable corrosion: Replace the cables.