Introduction

The walls of buildings have undergone a dramatic transformation over time. From thick, rough stone structures to the sleek, modern designs we see today, the evolution of wall construction reflects our changing needs and technological advancements. Let’s explore this fascinating journey and understand the key factors driving the changes.

The Early Days

In the early days of construction, walls were built using readily available materials such as stone, wood, bamboo, and grasses. Stone walls, while durable, were incredibly labor-intensive to construct. Wood and grasses, although easier to work with, were prone to deterioration. The development of baked clay bricks in the Middle East marked a major turning point, revolutionizing building practices worldwide. Later, concrete blocks became popular alternatives for many applications.

The Function of Walls

The fundamental purpose of walls remains the same:

• To support the roof
• To enclose the interior space, providing protection from the weather and helping to regulate temperature

However, different regions have addressed these needs in various ways. In Britain, for example, walls tend to be structural, supporting the roof with double layers of strong bricks or concrete blocks. In contrast, in America and Australia, buildings often feature a wooden frame that bears the structural load of the roof. This frame is then clad with internal plasterboard and an external veneer of siding or bricks.

The Rise of Cavity Walls

It was discovered that walls easily transfer heat, especially in cold climates where even the thickest walls could not retain heat effectively. The advent of cavity walls dramatically improved insulation. A cavity wall is a double-layered wall with an air gap between the two layers. This air gap acts as an insulator, significantly improving a building’s ability to retain heat in winter and keep it out in summer. The air gap also hinders the transfer of sound and prevents water from penetrating the inner wall. In many parts of the world, including Britain, cavity walls are a legal requirement.

In double-layered brick cavity walls, steel “ties” are embedded between the bricks to enhance the structural strength of the walls. In Australia and America, the air gap is within the wooden structure, with the internal layer being plasterboard and the external layer being a brick or siding veneer. Often, insulation material such as glass wool, aluminum foil, and waterproof membranes are added into the cavity for better insulation.

The advantages of cavity walls are:

• Improved Heat insulation
• Improved Sound insulation
• Reduced Water penetration

Despite these advantages, cavity walls are not commonly used in tropical climates, likely due to the increased building costs. The rise in air conditioning use may prompt the introduction of cavity walls in these regions. However, a double layer aluminum sandwich insulation fixed to the inner surfaces of solid concrete walls can provide similar results.

The Modern Marvel: Plasterboard

Another major advancement in wall construction is the development of plasterboard. Also known as gypsum board or drywall, plasterboard consists of a layer of gypsum plaster sandwiched between two pieces of cardboard. It is easy and quick to install, creating a smooth, flat surface. This is in contrast to the traditional plastering, a skilled trade, that is becoming less common due to the rise of plasterboard.

Plasterboard is widely used in tropical climates, particularly for ceilings. However, it has two main weaknesses:

• It breaks easily when impacted
• It is susceptible to water damage and can fall apart if it gets wet

Traditional Methods Persist

Despite these modern developments, many walls are still built using traditional methods. These walls use light concrete blocks covered with a thin layer of concrete. In the past, this method produced high-quality, stable finishes. However, modern applications often result in hard cement skins that crack and delaminate.

Conclusion

The journey of wall construction is one of continuous innovation and adaptation. From the heavy stone walls of the past to the insulated cavity walls and plasterboard finishes of today, each development has contributed to more comfortable and efficient buildings. These ongoing advancements demonstrate the importance of staying up-to-date with the latest building practices to ensure structures are not just functional but also sustainable and cost-effective.