What are Lintels? Types and Uses of Lintels in Building Construction

Lintels is a horizontal member which is placed across the openings to bear the load of above structure. In a building construction, there are windows or doors for which some space needs to be left. Above that space we can't directly put bricks and Hence, these are used whose some portion lies on sideways bricks and then, it helps to distribute loads.

Firstly, be clear that lintels are different from beams. A beam carries the load from slab and transfers it to columns to footing and then, finally to soil. But, lintels carries support of wall above it and then, transfers to adjacent wall portions.

What does opening corresponds to?

During, openings are left in wall due to doors, windows, cupboards, wardrobes, etc. Lintel on these openings supports the portion of wall situated above the openings and transmit the loads to adjacent wall portions.

History of Lintels

In classical western construction methods, a lintel is a load-bearing member and is placed over an open entrance way. But in ancient western classical architecture, it is called an architrave. It is a structural element that is usually rested on stone pillars or stacked stone columns, over a portal or entranceway.

In ancient, lintels were also used as a decorative building element overs portals, with no structure function. It has been employed in architectural traditions and styles of most cultures over the centuries.

Types of Lintels:

According to materials (like Timbers, Stone, Brick, Steel, etc.) used for construction, it has been classified into five types.

Timber Lintels

• These are provide over the width of wall and timber pieces are joined together by steel bolts.
• For better joints, mild steel plates are used at top and bottom. Then, it is also called fletched lintels.
• Easily available in hilly area because of the forests and hence, relatively cheap.
• But these are vulnerable to fire, structurally weak and can easily decay if it not properly ventilated.

Stone Lintels

• Commonly used in those places where stones are available in abundance.
• Consist of a simple stone stone slab of greater thickness. Secret joggles on keystone are made to join all stones.
• They are much more structurally strong than timber lintels.
• Used for span of 2 m.

Brick Lintels

• Bricks are hard, well burnt, first class bricks.
• Suitable for small span less than 1m.
• The bricks having Frogs are more suitable because when filled with mortar, form joggles which increase the shear resistance of end joints, called as joggled brick lintel.

Reinforced Brick Lintel

• Suitable for large spans and heavy loads.
• Brick lintels are reinforced with mild steel bars and hence, structurally strong. Main reinforcements are provided at bottom of lintels.
• Commonly used because of its durability, strength and fire resisting properties.
• Bricks are arranged so that 2-3 cm wide space between adjacent bricks for the insertion of reinforcement.

Steel Lintels

• Provided at large opening and where the super-imposed loads are heavy.
• It consists of rolled steel joists or channel sections. Either used singly or in combination of two-three units and joined with bolts.
• When used singly, steel joist either embedded in concrete, and when more than one units are placed side by side, they are kept in position by tube separators.

RC Lintels

• In today's word, this one is most commonly used.
• Precast concrete lintels are used for smaller spans.
• It has replaced many other lintels because of its strength, rigidity, fire resistance, economy and ease in construction properties.
• Longitudinal reinforcement in form of steel bars to resist tensile stresses and transverse reinforcement in form of stirrups to resist shear.