A Guide to Bricks, Blocks and Pavers

This article is an outline of various concrete bricks & blocks we have done in the past & can offer as custom moulds on request. This article is an overview; but ultimately each of these sections will become their own page with more information.

Standard Concrete Bricks

Standard bricks are the starting point in construction. They offer the most viable way to transport building materials and fill up outlined spaces between supporting structures; or act as supporting structures themselves.

Standard Concrete Blocks

Concrete blocks are building units that have met a size criteria that graduates them from the term "brick" as a description. Most blocks you are familiar with have two or more cavities. These act as a benefit, volumetrically, in that they allow a wall to be build with fewer resources.

Cavity blocks also provide a benefit of insulation when it comes to both thermal conductivity as well as weather factors (mostly rain water absorption in particular). Whilst concrete is generally colder than clay brick counterparts, the cavity block is superior to solid bricks because of these intracellular spaces.

Another benefit is that for hollow-through cavities, blocks can act as a scaffold for inserting rebar structural steel and pouring concrete into columns to provide additional strength (tensile from the steel & compressive from the solid concrete).

Decorative Breeze Blocks

Decorative breeze blocks are used for aesthetics as well as function. Whilst not functionally utilised for structural support, they offer airflow between spaces without allowing actual access. This can be for security (protection of copper pipes on the outside of a building or an adjoining courtyard) or for something like a refuse area.

Aesthetically, these blocks can be used near a top of a wall to add a style to an otherwise solid boundary wall.

Retaining Wall Blocks

Paving Bricks

Paving is so important that it constitutes its own category when considering building materials. Choosing a paving brick will allow for a style to match the vision of a home's aesthetic.

Various paving bricks can be combined in a multitude of ways; and adding colour variation to create patterns makes for visually appealing options leveraged by the creativity of the paver.

Lintel U-Blocks

Purchasing lintels can be expensive or inaccessible in rural areas. However, lintels can be cast on-site. The U-Block allows for a scaffold in which concrete is poured over rebar steel (for tensile reinforcement) to be used (upside down) above windows and door frames.

Stretcher Blocks

While standard blocks have strength gathered at the ends where only a layer of mortar mix separates the end bridges of two blocks in a row, stretcher blocks have a more uniform distribution of load-bearing across the distributed bridges when laid. Usually seen with three cavities, a row of blocks offers continuous cavity spacing which also provides normalised distribution of concrete slurry poured into the spaces.

Interlocking Blocks

The name is somewhat misleading - whilst the blocks may interlock to some degree of fit, eliminating mortar mix to set a wall is not advised. The interlocking notches allow for easy alignment of blocks and reduced horizontal mortar usage; but the true benefit is a huge increased in wall strength laterally where each block is secured by the block on either side.

Knock-out Blocks

Conduit channels and piping have to be taken into consideration when constructing a wall. Using knock-out blocks allows for an easy way to break apart the top of bridges to lay inserts. These knocked-out gullies can also be used for horizontal rebar steel reinforcement.

Rib / Deck blocks

Building double-storey requires a cast slab spanning the length and breadth of the floor space. For support, pillars are constructed to take the weight of the floor; but to pour the actual flooring you would use a deck block (or rib block). Typically, lintels are placed along the distance between the support walls. Between the lintels you have columns of these blocks to create a scaffold for the poured concrete to be held in place whilst curing. The sloped angle of the block creates archways for the concrete slab to rest upon the cross-support lintels.

Corner Blocks

In all building systems there is a relationship between the width of the wall and the length of the building unit. For most of the conventional sizes, the is an accumulated gap where the length of a wall meets up with its right-angle counterpart. Corner blocks are specialist blocks that provide a single-cast unit to meet that gap; as opposed to simply using a half-block to fill it.

Half Blocks

In place of corner blocks or for door-frames and other in-wall structures, the half-block allows for a gap-filler on alternate rows of blocks to create vertical surfaces.

Sill Blocks

As an aesthetic finisher to a window frame, consider a row of sill blocks. The occupy a single building unit in height but provide a nice finish to an otherwise flat-frame.

Wall Pillar Blocks

For boundary walls of a certain thickness, support structures are necessary at periodic intervals. This ensures the longevity of the wall and creates strength points along its span. Aside from strength, it is aesthetically superior than a plain wall. These blocks offer various combinations one requires.

Wall Caps

Whether using a wall pillar or not, a wall cap is a very neat finish to a wall. It also hides and protects cabling that could run along the top of the wall to light points, surveillance cameras or electric fencing. Adding an oxide for colour and the structure can be very attractive for something that exists to prevent trespassers.

Curb Stones

All along the road side and walkways of public parks you will find curbing. Curb stones are usually made with vibrating tables in a mould using the wet mix method. The mould is poured with concrete, left to set, and demoulded before a period of curing ensues.

Grassblocks

For muddy areas or grass paths that can be prone to erosion from car tyres, the grassblock is a solution to both offering grip for the rubber treads as well as protective the ground for vegetation to rebuild.

Roundhouse Blocks

Roundhouse, reservoir or South African "rondawel" (rondavel) block is an interlocking solution for creating a cylinder structure of a given diameter. As a water holding vessel, the blocks inter-connect to meet back up in a circle; and after several levels, reinforcement is applied in the cavities and waterproofing on the inside of the holding area before being capped to prevent evaporation.

Alternatively, as an abode - several layers are built to create a home space in the style of many rural dwellings of the Eastern Cape up to KwaZulu-Natal.