ADRIN SARWAR

Building a home requires more than just hiring a contractor. Landowners need to monitor these things for ensuring the safety and longevity of their investment.

Structural Steel (Rod) Quality

• Ensure the use of Grade 500W (72.5 TMT) or Grade 400 (60-grade) rebars. Grade 500W is preferred for modern high-rises.

• Verify that the diameter (e.g., 10mm, 12mm, 16mm, 20mm, or 25mm) matches the structural engineer’s drawing exactly.

• Rods should be free of heavy rust or scales.

Cement & Concrete Mix

• Use OPC (Ordinary Portland Cement) for columns and beams for faster strength gain, and PCC (Portland Composite Cement) for plastering and walls.

• Look for the BSTI seal on bags. Check the manufacturing date (cement loses strength after 3 months).

• For standard RCC (Reinforced Cement Concrete), a common ratio is 1:1.5:3 (Cement:Sand:Stone chips).

• Use crushed stone chips for columns and foundations for higher load-bearing capacity.

Earthquake Resilience (Seismic Safety)

• Ensure “Stirrups” (the rings holding the main rods) are spaced closely near joints and have 135-degree hooks to prevent the column from bursting during a quake.

• Verify the depth matches the Soil Test Report.

Fire Safety Measures

• Buildings over a certain height must have two exit points. Check if the stairwell width meets the code (min 1.1m to 1.5m depending on building type).

• Ensure high-quality FRLS (Flame Retardant Low Smoke) cables are used to prevent toxic smoke during a fire.

• If building a high-rise (above 7 stories), fire-rated doors are mandatory for stairwells.

Plumbing & Damp-Proofing

• Ensure a DPC((Damp Proof Course) layer is applied at the plinth level to stop moisture from rising into the walls.

• Ensure sewage pipes have a minimum 1:80 slope to prevent clogs.

Documentation & Verification

• Ask the company for a steel tension test test report from BUET or PCSIR for the specific batch of rods delivered.

• During casting the contractor should take samples to a lab to test “Crushing Strength” after 7 and 28 days.

• Ensure the construction matches the RAJUK (Dhaka), CDA (Chittagong), or Pourashava approved plan to avoid future demolition orders.