Prefabricated and Non-prefabricated Floor Slabs

Prefabricated floor slabs are concrete slabs manufactured in a factory and then transported to the site for installation, while non-prefabricated slabs generally refer to cast-in-place slabs. There are significant differences between the two in terms of construction, quality, cost, etc..

Construction

Prefabricated slabs are like "semi-finished products" produced in a factory. After being transported to the site, they can be directly laid without the need for on-site concrete mixing, formwork erection, or waiting for hardening. This can significantly shorten the construction period, especially suitable for scenarios in the early days of rural areas where transportation was inconvenient and concrete mixing plants were not widespread. It also reduces labor costs and material waste. Cast-in-place slabs, on the other hand, require on-site formwork erection, steel bar tying, concrete pouring, and waiting for hardening, resulting in a long construction cycle and high labor and material costs.

Quality

Prefabricated slabs are produced in a factory with standardized processes, ensuring a uniform internal load-bearing structure and better quality controllability compared to on-site mixed concrete, reducing construction errors. Although cast-in-place slabs are poured as a whole, their quality depends on the on-site construction level. If the mixing ratio is inaccurate or curing is improper, it may affect the structural stability.

Integrity and Seismic Resistance

Prefabricated slabs are composed of multiple slabs spliced together, resulting in poor integrity. In the event of an earthquake or foundation settlement, the slab joints are prone to displacement, and in extreme cases, the floor slab may slide off. Cast-in-place slabs firmly connect the walls and floor slabs through integral pouring, forming a "hoop" effect, and their seismic performance is significantly better than that of prefabricated slabs.

Cost and Environmental Protection

Prefabricated slabs can reduce on-site labor and time costs, as well as waste and noise, making them more environmentally friendly. However, if reinforcement (such as adding ring beams or structural columns) is required, the cost may approach or even exceed that of cast-in-place slabs. Cast-in-place slabs have higher initial costs but lower long-term maintenance costs and do not require additional reinforcement.

Daily Use and Maintenance

Prefabricated slabs may have issues with joint water leakage, especially in wet areas such as kitchens and bathrooms. When maintenance is required, only the damaged slab needs to be replaced, making the operation simple. Cast-in-place slabs have no joints and good waterproof performance, but if cracks occur, the entire slab needs to be treated, making maintenance more difficult.

Design and Transportation

The size and weight of prefabricated slabs are limited by transportation conditions, resulting in lower design flexibility and suitability for standardized buildings. Cast-in-place slabs can be poured on-site according to needs, supporting complex structures and personalized designs, but require advance planning of formwork and steel bar layouts.