Renovation of Single-Story Prefabricated Slab Houses

The renovation of single-story prefabricated slab houses requires an assessment of applicability based on specific needs, with a focus on structural safety, functional upgrades, and construction specifications, as detailed below:

I. Applicability Assessment
For single-story bungalows in rural areas, renovating with prefabricated slabs offers advantages such as a short construction period (3-7 days for the main structure), low cost (30%-50% lower than cast-in-place structures), and adaptability to soft soil foundations (reducing settlement risks). However, the following conditions must be met:

1. Usage Limitations: Only suitable for temporary buildings or light-structure houses, with a single-slab load capacity of ≤200kg/㎡. Not suitable for heavy roofs or second-story additions.
2. Geological Conditions: Soft soil foundations should prioritize prefabricated slabs to reduce settlement risks, but proper foundation treatment must be ensured.
3. Seismic Requirements: In areas with a seismic fortification intensity of 7 degrees or higher, steel reinforcement must be added; otherwise, seismic performance will be inadequate.

II. Key Construction Points

1. Foundation Treatment:
   • A 30cm thick gravel cushion + 15cm plain concrete leveling is required to ensure a flat and solid foundation.
   • For old houses with foundation settlement, pile reinforcement or other foundation treatment techniques should be applied first.
2. Installation Specifications:
   • Install slabs from the corners of the house towards the center, with staggered joints to avoid continuous seams that weaken the structure.
   • Fill gaps between slabs with C20 fine aggregate concrete to prevent water leakage and structural loosening.
3. Waterproofing and Reinforcement:
   • An additional SBS modified asphalt waterproofing layer should be laid on the roof slabs to address roof leakage issues.
   • Old houses should first undergo a comprehensive inspection by a professional team to develop solutions for issues such as wall cracks and steel bar rust, such as grouting for small cracks and steel plate reinforcement for severe cracks.

III. Material and Functional Upgrades

1. Material Selection:
   • Recommended slab specifications: length 3-6m × width 0.5-1.2m × thickness 12-18cm, with a strength grade not lower than C30 concrete standard.
   • Reinforcement requirements: main reinforcement diameter ≥8mm, spacing ≤15cm, to ensure structural durability.
2. Functional Optimization:
   • Improve sound insulation: Install soundproof panels on walls and replace windows with double-glazed units.
   • Enhance living experience: Add insulation layers, ventilation systems, or modern decorations as needed.

IV. Precautions
Before renovation, a comprehensive assessment of the house's current condition is necessary to avoid safety hazards caused by blind construction. If structural modifications (such as wall removal or additional stories) are involved, a reinforcement plan must be designed by a professional engineer and comply with local building codes.