House Extension Contractors in Kundrathur

If your house in Kundrathur is starting to feel tight, house extension contractors in Kundrathur are usually brought in for one clear reason: you need more usable space without giving up the plot you already own. It may be a first-floor room, a rear kitchen block, or a terrace room for a growing family.

We handle extensions as real structural work, not just a bit of extra masonry. That means checking the old house first, matching the new work to the existing footing and frame, and getting the approval route right before you spend on drawings or material.

Kundrathur and what changes on site

Kundrathur is outside the Corporation side of Chennai, so the licence route is different from central city plots. You usually deal with the local municipality or town panchayat side, while CMDA remains the planning authority for the metropolitan area. That matters because extension work is rarely only about adding walls; it also means checking whether your existing house papers, drawings and drainage details line up with what the local body will ask for.

In this part of the city, many plots are still family houses with later additions done in phases. Some sit on narrower approach roads, some have little space for stacking bricks or sand, and some were built before current design practice. A first-floor extension on such a house needs more than a mason and a shuttering crew. It needs a proper look at load path, old concrete condition, and how the new roof will meet the old one without cracking at the joint.

The ground side also matters. In west and south-west Chennai, including Kundrathur, the soil can be firmer than the low-lying marsh side of the city, but you never assume that for a specific plot. We still ask for a soil investigation before foundation design. If the log shows soft layers or a weak patch, the right answer may be a raft, tie beams, or a different support arrangement. If it is firm, isolated or strip footings may be enough. The test is cheap beside the cost of repairing a settlement crack later.

What a safe extension really needs

An extension succeeds when the old and new parts behave like one building. That sounds simple until you see a top slab that was never meant for another floor, or a side wall that carries more than it should. We design to IS 456:2000 for RCC, IS 875 for loads, IS 1893:2016 for earthquake forces, and NBC 2016 for the broader building rules. Chennai sits in Seismic Zone III, so the frame, beam sizes and connections cannot be treated casually just because the house is “only one extra room”.

Before we touch the structure, we inspect the existing house for column size, beam continuity, wall cracks, roof slope, damp patches and any signs of old settlement. We also look at the service side: where the sump sits, how rainwater leaves the terrace, whether the septic line or drainage line can still work after the new block comes in, and whether RWH needs to be added or reworked. In Tamil Nadu, rainwater harvesting has been mandatory for years, and an extension should not make an already weak drainage situation worse.

Where people get it wrong

The common mistake is to treat extension work like a normal room addition. They add a staircase, close a balcony, or build a terrace room without checking whether the old columns were meant to take that extra load. Another one is skipping the joint detail between old and new masonry. That joint opens first in monsoon and gives you a fine vertical crack that keeps coming back. Paint hides it for a season. Structure does not.

1. Site inspection and measurement — We check the existing house, take actual dimensions, and note visible cracks, slope issues and access. This usually takes one visit, sometimes two if the house is occupied.
2. Structural review — Our civil engineer and structural engineer study the existing load path, the proposed addition and the available headroom. If needed, we ask for a soil investigation before foundation design.
3. Drawings and BOQ — We prepare the architectural and structural drawings, then a detailed BOQ so you know what is included before any contract is signed.
4. Execution and inspection — The site engineer is on site every working day, with stage checks for steel, shuttering, concreting, curing and waterproofing. Weekly photo updates are available if you cannot visit.

How to verify a contractor before you sign

If you are comparing firms for an extension, ask for the boring details. That is where the answer lives. A fair contractor should show you how the old structure will be assessed, what part of the work is structural, what part is finish work, and what happens if the existing house turns out weaker than expected. If someone gives you only a square-foot rate and a quick promise, stop there.

You should also ask what the contract contains. For extension work, the important parts are scope, drawings, BOQ, payment stages, who handles approvals, what happens to hidden defects found during demolition, and whether the new work includes waterproofing, drainage changes and final handover documents. A proper contract is not long for the sake of it. It is specific where disputes usually happen.

• Ask for the existing-house assessment before they quote a final number.
• Check whether steel, cement, waterproofing and labour are all included in the same scope.
• See the payment stages in writing, not only a verbal plan.
• Confirm who will deal with approval drawings, structural drawings and drainage details.
• Ask how the joint between old and new work will be treated.
• Ask what happens if the roof slab or column shows hidden damage during opening work.

Cost, approval and time

For residential extension work, the rate usually sits inside the standard residential or mid-premium construction bands, depending on finish level and how much of the old building needs strengthening. As a reference, standard residential construction is ₹1,900 to ₹2,300 per sq ft, mid-premium is ₹2,300 to ₹2,800 per sq ft, and premium can go higher. That figure moves with soil and foundation type, number of floors, span, finish level and site access. A detailed BOQ settles the real figure before any contract.

Approval time depends on the plot and the nature of the addition. If the house sits inside a local body area with clear papers, the route is usually smoother. If the plot is old, split across family members, or missing drawings, the paperwork takes longer than the brickwork. Near the airport side of Chennai, height clearance can also matter, but Kundrathur is usually not where that problem starts. The real issue here is often document cleanliness and whether the existing house was built from a plan or from memory.

How we work on extension projects

We keep the technical work in-house. Our civil engineers, structural engineer and architect work on the drawings and site checks, and a site engineer attends the site every working day. Mr. D. Salamon Ashok Rajan reviews the project as Managing Director, which helps when an old house throws up a problem that needs a quick engineering call, not a long email chain.

Before we start, we give you a BOQ, a milestone-linked payment schedule and a clear scope. If you cannot come often, we share weekly WhatsApp photos. If you want to speak to us about your extension in Kundrathur, call +91 97107 13838 or write to info@shalomconstruction.com. Our office is at No. 45, 2nd Main Road, Abirami Nagar, Koladi, Thiruverkadu, Chennai – 600077.

Frequently Asked Questions

If you are planning a house extension in Kundrathur, the best time to start is before the old walls get opened and the site becomes messy. We can help you confirm what is possible, what needs strengthening and what the real BOQ should contain.