Guide

What the 34 checks actually measure

Not a quality claim. A list of measurements taken off the drawing at build time, and what happens when one fails.

Why typed dimensions fail when you start to build

When you look at a floor plan on a screen, the rooms look clean and functional. You see lines for walls, symbols for furniture, and text labels showing room dimensions. The drawing seems complete, but a typed dimension is only text placed on a computer screen. It does not prove that the clearance between the bed and the wall lets you walk past without turning sideways.

When an unverified drawing reaches your site, drafting errors turn into physical masonry. A mason builds a 110 mm partition wall where the drawing indicates, only to find the hallway is too narrow to use comfortably. A plumber sets pipes in concrete, only to find the septic tank sits dangerously close to your borewell.

Fixing these mistakes during construction wastes time and money. Demolishing fresh masonry, rerouting underground pipes, or cutting down custom joinery inflates your expenses. A plan must verify every clearance against the physical geometry of the drawing before work begins.

The thirty-four rules across five categories

To make sure a layout works on site, every line must satisfy five distinct categories of spatial rules. These rules come from national codes, state regulations, and practical geometry.

The first category is clearances. The National Building Code Part 3 sets the minimum clear width for general circulation and corridors at 914 mm. Our own practice establishes 914 mm as the preferred clear floor space beside a bed, backed by IS 8888 space standards, with 600 mm as an absolute floor only on a secondary side. For kitchens, our practice requires a 1220 mm aisle between facing counters for two people working. In bathrooms, our practice requires 760 mm clear in front of a W.C. pan and a 914 mm short side for a shower compartment.

The second category covers air, light, and heat. The National Building Code Part 8 requires openings on two different faces of every habitable room for cross-ventilation. For wet compartments, our practice and the National Building Code Part 8 require that every bathroom touches an external wall with its own high-level louvre. Climate geometry at 8 to 16 degrees North requires an external shading projection of at least 600 mm over a 900 mm sill, and an eaves depth of 900 mm to stop direct solar heat.

The third category governs plan form. Our practice requires that circulation never crosses the front of a bed. A bed head must rest against a solid wall, never against a wall shared with a bathroom or a kitchen, and never under a window. The room sequence must flow from kitchen to dining to living.

The fourth category addresses site, water, and sanitation. IS 2470 and the Tamil Nadu Combined Development and Building Rules 2019 require a separation of at least 18 m between a borewell and a septic tank or soak pit. IS 2470 also requires a septic tank to sit at least 15 m from the building, unless its vent pipe rises 2 m above the roof.

The fifth category is the door pass. Our practice checks every door swing across the house as one unified pass. No door may swing into a corridor or lobby. Every door opening must lie inside a real wall, and no door leaf may strike a fixture or another door.

How automated checks test the layout

A checked plan does not rely on typed labels. Every dimension string on the drawing is measured at draw time, not typed. The software measures clear distances between wall faces and fixtures directly off the canvas geometry.

The system runs 34 named checks measured off the drawing at build time on a 995 sq ft house we drew. When a layout breaches a non-negotiable rule, the check produces a FAIL. A FAIL stops the drawing being produced at all. If a corridor narrows below standard or an opening falls outside a wall, the process halts until the layout is corrected.

When a site constraint makes an ideal rule impossible, the system issues a WARN. A WARN is reported with its number so you see the exact compromise. For example, on a 60 by 90 ft plot the septic tank could not be 15 m from the house. The tool issued a WARN with its number. It then applied the alternative rule from IS 2470, requiring the vent pipe to rise 2 m above the roof.

On a 995 sq ft house we drew in Narasipuram in Coimbatore district, all thirty-four checks were measured at build time. On that 9,150 by 10,100 mm footprint, the master bedroom measured 3,450 by 3,300 mm. With a 1370 by 1900 mm double bed, the measured clear space came out to 965 mm on each side and 1,550 mm at the foot. The second bedroom measured 985 mm clear on each side. The measured distance from the septic tank to the borewell reached 25.9 m, safely beyond the 18 m minimum required by IS 2470.

The costly errors these checks catch

Automated geometric checks catch defects that human drafting reviews regularly miss. In our own project drawings, automated checks caught six critical defects that had passed human review.

In one drawing, a corridor finished at 804 mm clear instead of 914 mm. A human designer measured from the wall centerline, but the 110 mm partition wall ate into the path. This cost 110 mm of clear space on the busiest route in the house.

In another plan, two 900 mm doors started 60 mm inside a 914 mm corridor, so the openings ran past the far jamb. In a bedroom, a door leaf struck a wardrobe by 567 mm, preventing the door from opening fully. In a bathroom, a door leaf struck a vanity by 290 mm, which forced the vanity to be shortened.

A separate check caught six of ten door openings drawn beside their walls rather than inside them. On another plan, a septic tank landed 2.6 m from the house because of an unadjusted plot fraction. The check caught the error, redirecting foul drainage to the plot corner furthest from the borewell.

Preventing these errors protects your construction budget. In India in 2026, basic finish construction costs ₹1,600 to ₹2,000 per sq ft. Standard finish costs ₹2,000 to ₹2,800 per sq ft, and premium finishes reach ₹2,800 to ₹4,500 or more per sq ft. For a 995 sq ft house, a basic rate of ₹1,700 per sq ft totals about ₹16.9 lakh. Reworking masonry and moving plumbing lines on site directly wastes those funds.

What this means for your plan

Check your room clearances, door swings, and plumbing setbacks before you begin construction. The tool applies every one of these thirty-four rules automatically when it draws your plan. Keep in mind that this layout provides a verified concept sketch rather than a construction drawing. Every jurisdiction requires drawings stamped by a licensed architect or engineer before a permit is issued.

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