Put the wiring in before the wall sets.
Conduit, back-boxes and sensor pockets placed in the mould and cast into the element. Not chased into finished plaster with an angle grinder.
Almost all precast built in India is justified by cost and speed — mass housing, labour shortages, government schemes. That framing has left the method with a reputation for being the budget option, and kept it out of the homes where its advantages would matter most.
The advantages are not financial. Factory tolerances buy things site construction cannot deliver at any price. Flatness measured in millimetres across a whole wall. Services exactly where the drawing put them. A finish that is cast rather than applied.
A well-finished panel is copyable within two years by any plant that decides to try. A panel with the control system designed into it is not — that needs a plant that has become a technology company, or a technology company that has learned concrete.
Casting a conduit into one panel is easy. Making it line up with the next panel’s conduit — on a crane, in dust, with real erection tolerance — is the problem that decides whether any of this works.
The answer is not a tighter tolerance. It is an oversized coupler sleeve at the joint with a draw-wire already through it, so the grout joint absorbs the movement instead of the conduit fighting it.
Inserts move during the pour. Vibration shifts anything not rigidly fixed to the bed, and a box that migrates 20 mm is in the wrong place forever. Boxes get magnetic or bolted fixings, and a self-compacting mix removes the need to vibrate at all.
Voids beside the boxes. Every insert creates congestion, and conventional concrete leaves air pockets there. A void next to a back-box is a water path and a weak point. Self-compacting mix flows through without vibration — which is why the mix and the module are one design problem, not two.
Steel congestion at openings. Each void interrupts the reinforcement mat and needs trimmer bars. Cluster boxes to make the wiring tidy and you can create a genuine structural problem. Every layout goes to the structural consultant before it goes to the mould.
Precast is a mould business. A steel mould runs ₹1.5–6 lakh and casts hundreds of times; plywood is cheaper and lasts thirty. One house with forty unique panels is financially miserable. One house with eight panel types repeated forty times is ordinary.
So we design a library, not a house. Customisation happens in how elements are arranged, not in whether each one is new. It is the same discipline the Japanese housing makers hold — and the hardest one to keep when a client with money asks for something special.
Panel elevation with dimensions, weight, concrete grade and finish face. Reinforcement drawing showing how the mat is modified around every void — the drawing that needs a stamp. Cast-in items schedule positioning every box and sleeve in X, Y and Z from a fixed datum, with tolerance stated rather than implied. Lifting anchor layout with demoulding, handling and erection load cases. Connection details, including how conduit continues across the joint. And the mould drawing — the negative, with the fixing method for every insert.
We design the element and the system inside it. Structural design and certification are produced and stamped by a qualified consultant; elements are manufactured by established plants. That division is deliberate and permanent.