Brick & Block Calculator

Standard Brick Sizes Used in India

Indian construction uses two primary brick standards. Modular bricks (190×90×90 mm with mortar, 190×90×90 nominal) are used in most new construction and are designed to maintain a consistent module. Non-modular (traditional) bricks are 9×4.5×3 inches and are more commonly found in older or budget construction. Concrete Hollow Blocks (400×200×200 mm) are the third option — they are lighter, provide better thermal insulation, and lay faster but cost more per unit. Our calculator handles all three.

4.5 Inch vs 9 Inch Walls: Which to Use

A 4.5-inch wall (bricks laid on their side, half-brick thick) is fine for interior partitions and compound walls that do not carry structural load. A 9-inch wall (bricks laid flat, full-brick thick) is mandatory for external load-bearing walls, retaining walls, and any wall that carries beam or slab loads. In frame-structure buildings (RCC columns and beams), partition walls can safely be 4.5 inches. In load-bearing structures, all walls must be 9 inches minimum.

Mortar Mix Ratios and Quantities

The standard mortar mix for brickwork is 1:6 (cement:sand) for interior walls and 1:4 for areas exposed to rain or moisture. Mortar joints are typically 10–12mm thick. For every cubic meter of brickwork, you will need approximately: 500 bricks, 0.35 cubic meters of mortar, which translates to 2 bags of cement (50kg each) and 0.25 cubic meters of sand at a 1:6 ratio. Cement should be stored off the ground and used within 3 months of manufacture.

Hollow Concrete Blocks vs Fired Bricks

Hollow concrete blocks (also called CMU or AAC blocks) are increasingly popular in modern construction. They lay 3–4× faster than bricks, weigh less (reducing structural load), and provide 30–40% better thermal insulation — important for reducing AC costs. Their downside is higher unit cost and lower compressive strength, making them unsuitable for load-bearing use without special engineering. AAC (Autoclaved Aerated Concrete) blocks are the premium variant — extremely light, great insulation, but require special mortar and skilled labor.

Brick Quality Checks Before Buying

• Ring test: Strike two bricks together — a clear ringing sound indicates good quality.
• Absorption test: A good brick absorbs less than 15% of its weight in water after 24 hours of soaking.
• Scratch test: A nail should not easily scratch the surface — soft bricks are under-fired.
• Uniform color: Consistent red-orange color means even firing throughout the kiln batch.
• Sharp edges: Edges and corners should be sharp and well-defined, not rounded or chipped.

Site Planning Checklist

• Order 5–10% extra to account for breakage during transport and cutting at corners.
• Store bricks on a raised platform to prevent ground moisture absorption.
• Cure brickwork for at least 7 days by keeping it wet — this dramatically increases strength.
• Use a spirit level constantly — even small deviations in the first few courses compound upward.
• Plan door and window openings in advance to minimize cuts and wastage.