Pre-cast concrete blocks are made from cement, sand, and gravel, and they tend to get stronger over time, thus make them a great choice for building.
Concrete has been used in construction since the late 1800s. It was first used in South Africa when the first reinforced concrete, coal-washing plant was constructed in Vereeniging in 1929.
Pre-cast concrete blocks come in different shapes and sizes.
They can be used for a variety of purposes, from foundations to walls and floors. Pre-cast concrete blocks are affordable because they allow for rapid construction on any project, saving not only time but money.
These concrete blocks are economically feasible and durable. They can resist a wide range of deteriorating agents while maintaining their original strength and aesthetic appeal.
Concrete blocks use less jointing material due to their larger size and regular shape. They also require less plastering. The blocks are less absorbent than bricks, so they also reduce dampness in the walls. They are very easy to work with, so they’re also perfect for your home décor projects!
What about eco-efficiency?
Low-maintenance concrete homes are a great investment for many reasons. They are energy efficient, so can meet the energy needs of any project. They are resistant to natural disasters such as fire, and they reduce noise by almost 1/4, . When the design of a building is done well, the pre-cast concrete blocks help to cool down during summer, and warm up during winter, so they reduce running costs.
Concrete masonry also has low embodied carbon compared to other building materials, and permanently isolates carbon dioxide throughout its lifetime.
PJ Projects offers two types of pre-cast concrete block: solid pre-cast concrete blocks, and hollow pre-cast concrete blocks.
Solid Pre-cast Concrete Blocks:
These blocks have high density and are 55% solid, sturdy, and give structures a lot of solidity. These solid blocks are great for any scale project. PJ Projects produces The Maxi / RDP Brick, which only needs 33 bricks to cover one square metre.
The M6 Building Block – the big brother to the Maxi Brick – requires 12 bricks per square metre.
Hollow Pre-cast Concrete Blocks:
These blocks are manufactured in a range of sizes to provide the designer with full flexibility to determine an appropriate slab depth and rib arrangement to suit their needs. Hollow concrete blocks are typically employed in building and fabricating construction. This reduces the cost of cement, steel, and labour costs on the job, while speeding up the construction process.
These blocks reduce the natural weight of masonry structures while also improving physical wall qualities like noise reduction and thermal insulation.
Hollow pre-cast concrete blocks come in various shapes, sizes, and designs, depending on the shape, needs, and design. The Hollow Block comes in the following sizes:
FT110 – Depth: 110mm x Width: 500mm x Length: 200mm – Approx. Mass Per Block (20KG)
FT140 – Depth: 140mm x Width: 500mm x Length: 200mm – Approx. Mass Per Block (21KG)
FT200 – Depth: 200mm x Width: 500mm x Length: 200mm – Approx. Mass Per Block (26KG)
FT250 – Depth: 250mm x Width: 500mm x Length: 200mm – Approx. Mass Per Block (31KG)
Blocks are manufactured under strict control procedures, from concrete with a 28-day cube strength. This ensures that, when tested in a compression testing machine, they have a minimum crushing strength of 7MPa measured on the net section when axially loaded in the direction of compressive stress in the finished slab.
Hollow pre-cast concrete blocks are also available in polystyrene, which is 90% lighter than concrete blocks, therefore reducing 1.6KN/m2 of dead load. This is approximately 140kg per m² on a 255mm slab. Compared to an in-situ, the weight saving is even greater – being 320kg per m2! The lower-weight advantage allows engineers to use polystyrene slabs on buildings where the foundation history is unknown.
PJ Projects has been manufacturing pre-cast concrete rib and block first-floor slabs for more than 20 years.
We are big enough to provide all your pre-cast concrete requirements, but small enough to build a relationship with you. We are well-known for our reliability and prompt service.
PJ Projects is situated in Cullinan, just outside Pretoria. We supply pre-cast concrete rib and block first-floor slabs to building contractors, developers, and individual builders in the whole of Gauteng, Limpopo, and Mpumalanga provinces. We deliver within a 300km radius of our yard.
Our value-added services
We know the cost of construction – especially if contract deadlines are not met! PJ Projects is committed to making it easy for you to obtain concrete material, in time and on budget. We take pride in the quality of our products and offer value-added services for your convenience:
- On request for a quotation, building plans are collected or emailed.
- Should an engineer’s appointment letter be required, it can be arranged with our office.
- An engineer’s site visit will take place after installation.
- A certificate will be issued upon completion.
Contact us today to request a quotation or contact our offices for any queries you may have.
Office Telephone: 012 736 9056 or Mobile: 072 049 9560