Atlas of Roof Construction Practices for Prefabricated Slab Houses

For the roof construction practices of prefabricated slab houses, refer to the following atlases and technical highlights:

1. "Prefabricated Ribbed Base Plate Concrete Composite Floor Slabs" (Hunan 2021 G301)
This atlas, issued by the Hunan Provincial Department of Housing and Urban-Rural Development, is applicable to the design of floor and roof slabs in areas with seismic fortification intensities ranging from 6 to 8 degrees. Its core contents include:

• Types of Prefabricated Base Plates: Utilizes prestressed concrete ribbed base plates, with rib shapes categorized as rectangular, T-shaped, or wedge-shaped, enhancing overall structural integrity.
• Span and Post-Cast Layer: The composite slab spans range from 3 to 9 meters, with the post-cast layer thickness required to be no less than 1.3 times the thickness of the prefabricated base plate, ensuring structural safety.
• Node Details: Provides structural node construction drawings, covering key areas such as slab end connections and support treatments, directly applicable for construction guidance.
• Access Method: Available for free download from the official website of Hunan Provincial Architectural Standard Design Atlases, suitable for standardized design needs.

2. Prefabricated Roof Node Drawings (Unnumbered)
This set of drawings includes 9 architectural node details, focusing on resolving roof waterproofing and structural connection issues:

• Waterproofing Construction: Specifies the lapping sequence and material requirements for each structural layer of the prefabricated roof (e.g., leveling layer, waterproofing layer, protective layer) for Grade I fortification requirements.
• Flashing Treatment: Provides node drawings for gable and longitudinal wall flashings, preventing rainwater backflow through metal pressing strips or sealant caulking.
• Expansion Joint Design: Differentiates between equal-height and unequal-height expansion joints, using elastic material filling or cover plates to accommodate roof thermal expansion and contraction.
• Slab Joint Treatment: Defines sealant materials and construction depths for different slab joint forms, such as ridge joints and butt joints, to prevent leakage.
• Ancillary Components: Includes details such as internal gutter drainage slopes and eave wind-uplift prevention, enhancing roof functionality.
  Although this set of drawings lacks an atlas number, the node details can be directly referenced, suitable for localized structural detailing design.

3. Typical Drawings for Roof Photovoltaic Installation on Prefabricated Slabs (PDF Format)
This set of drawings provides a structural solution for inclined roof photovoltaic systems, with attention to applicable conditions:

• Structural Layers: Adopts a combination of cast-in-place reinforced concrete flat roofs + wooden beam purlins + red tiles/glazed tiles, requiring assurance that the original roof structure's load-bearing capacity meets requirements.
• Restrictions: Explicitly excludes scenarios such as dilapidated houses, flat roof leaks, occupancy or renovation beneath the tile layer, to avoid structural safety hazards caused by photovoltaic installation.
• Download Method: Requires points redemption to obtain the PDF file, suitable for specialized photovoltaic project design reference.

Recommendations:

• For standardized design, prioritize the use of the Hunan 2021 G301 atlas, with its authoritative technical parameters and node details;
• For localized structural detailing, supplement the design with the 9 unnumbered node details;
• For inclined roof photovoltaic installation, strictly assess the house's current condition to ensure compliance with applicable conditions before referencing the relevant drawings.