How to Prefabricate the Roof Surface of a Terrace

The treatment of the prefabricated roof surface of a terrace can be carried out according to the following steps, requiring scientific construction that combines structural safety and functional requirements:

1. Mortar Layer Application and Base Leveling First, apply a concrete mortar layer approximately 5 centimeters thick on the prefabricated roof surface as the foundation for subsequent construction. The material should be cement mortar, which needs to be thoroughly mixed before construction to achieve a uniform state, avoiding particle sedimentation or uneven wetness and dryness. During application, use a trowel to compact the layers gradually, ensuring that the surface flatness error does not exceed 3 millimeters. Simultaneously, use a level to check the overall levelness to prevent water accumulation or uneven structural stress due to tilting. After the mortar layer dries, perform a roughening treatment to enhance the bonding strength with the insulation layer.

2. Insulation Layer Construction Select insulation materials based on local climate conditions, with common options including expanded polystyrene (EPS) boards or polyurethane foam (PU) boards. In cold regions, it is recommended to use XPS extruded polystyrene boards with a thermal conductivity of ≤0.032W/(m·K) and a thickness of no less than 5 centimeters; in temperate regions, EPS boards with a thickness of 3 centimeters can be selected. During construction, lay the boards with staggered joints to avoid thermal bridging effects, and secure them with special adhesives or anchors to ensure complete adhesion to the mortar layer. The edges of the insulation layer should extend to the inner side of the parapet wall to form a continuous insulation zone.

3. Waterproof Layer Treatment Waterproofing is a core aspect of terrace construction. The base treatment requires thorough removal of dust and oil stains, and repairing cracks with cement mortar. Any protrusions should be ground smooth. Waterproof materials can be selected from polyurethane waterproof coatings or SBS modified bitumen waterproof membranes:

• For coating application, apply 2-3 coats with a total thickness of ≥1.5 millimeters, with each coat applied perpendicular to the previous one. Reinforce corners with non-woven fabric.
• For membrane application, first apply a base treatment agent, then lay the membrane using hot melt or cold adhesive methods, with an overlap width of ≥10 centimeters. Additional layers should be applied at nodes such as parapet walls and pipe roots. After the waterproof layer is completed, conduct a 48-hour closed water test to confirm no leakage before proceeding to the next step.

4. Prefabricated Terrace Installation (Optional) If using a modular prefabricated terrace, confirm the load-bearing capacity of the steel structure in advance. During installation, note the following:

• The steel structure frame should be fixed to the roof embedded parts using chemical bolts, with anti-corrosion treatment applied to the connections.
• Fill the joints around the perimeter with silicone weather-resistant sealant with a thickness of ≥5 millimeters to form an elastic seal.
• Reserve a drainage slope of 2%-3%, with the floor drain position being 10 millimeters lower than the terrace surface. The drainage pipe diameter should be ≥75 millimeters and equipped with a trap.

5. Surface Decoration and Protection Select decoration materials based on usage requirements:

• For residential terraces, it is recommended to lay non-slip tiles or anti-corrosion wooden flooring. The wooden flooring should be installed on a raised frame with expansion joints reserved.
• For landscape terraces, pebble paving or artificial turf can be used, with a geotextile laid first to prevent weed growth.
• The top can be installed with lightweight aluminum ceiling panels, which provide both sunshade and concealment of pipelines. All metal components should be treated for rust prevention, and wood should be coated with outdoor wood oil.

Construction Key Points: Throughout the process, strictly adhere to the principle of "combining prevention and drainage" to ensure the drainage system is unobstructed and prevent long-term erosion of the structure by accumulated water. If the load-bearing capacity of the prefabricated roof is limited, structural reinforcement or reducing the weight of decoration materials should be considered to meet safety requirements.