Six of ten doors in a set we drew were in the wrong place

A human had already reviewed them. The automatic check found six. This is what a checked drawing means.

Why door openings land off the wall and cost you money on site

You look at a floor plan sketch and every room seems clean. The lines connect, the bed fits, and the doors appear open. The problem begins when a mason and a carpenter arrive on your plot to build those lines.

A human eye reads a floor plan as an illustration. When a door arc touches a wall line, your brain assumes the door hangs inside that wall. Software drawings can place a door graphic 50 mm off the actual partition without you noticing. A mason reads exact coordinates or follows the nearest line. If a door opening sits beside a wall rather than inside it, the mason builds a rough opening in the wrong place.

Fixing misplaced openings on site wastes money. A mason must tear down fresh brickwork or a carpenter must order custom, narrow door leaves. If you catch the clash after casting concrete lintels, chipping concrete costs labor and delays construction. A concept sketch is only useful if its geometry matches real walls.

The numbers and clearance rules for doors, walls, and tanks

Every wall opening must sit within real physical boundaries. Dimensions from building standards and professional practice dictate how these openings behave:

The National Building Code Part 3 sets the minimum corridor clear width at 914 mm between finished partition faces.
Under National Building Code Part 3, internal partitions take 110 mm for burnt clay brick, 100 mm for concrete block, or 150 mm for RCC frame infill.
Our practice rules require every door opening to sit entirely inside a real wall.
Our practice rules flag a warning if a door leaf clears any fixture by less than 50 mm.
Wardrobes require a depth of 600 mm, with 150 mm surrendered when a swinging door leaf must clear the wardrobe face, according to our practice rules.
Under IS 2470, a septic tank must sit at least 15 m from a building unless its vent pipe extends at least 2 m above the roof.
Both the Tamil Nadu Combined Development and Building Rules 2019 and IS 2470 require a separation of at least 18 m between a septic tank and a borewell.
Under IS 8888 and our practice rules, clear floor beside a bed requires 914 mm preferred clearance, with an absolute floor of 600 mm on a secondary side.

How geometric checks catch what human eyes miss

Planning a house requires coordinating door swings, partition thicknesses, and furniture layouts at the same time. Doors represent the highest-leverage variable in your plan. You must review the hinge side, the swing arc, and the sight lines across the entire house as one exercise.

When you draft a plan by hand or review a visual drawing, human review fails to catch spatial misalignments. A reviewer looks at the room name and the rough flow. A mathematical check tests the exact coordinates of every jamb and leaf arc against the partition faces and adjacent fixtures.

In a plan set we drew for a 995 sq ft house on a plot in Narasipuram, Coimbatore district, a careful human review approved the drawing. Our automated checker then ran 34 geometric checks across the layout. The checker flagged six critical defects that human eyes completely missed.

Defect	What went wrong in the drawing	Practical consequence on site
1	Corridor measured 804 mm clear instead of 914 mm	Partition of 110 mm ate into circulation space
2	Two 900 mm doors started 60 mm inside a 914 mm corridor	Openings ran past the far jamb outside real walls
3	Bedroom door leaf struck a wardrobe by 567 mm	Door could not open fully past the wardrobe
4	Bathroom door leaf struck a vanity counter by 290 mm	Vanity counter had to be shortened on site
5	Septic tank placed 2.6 m from house by plot fraction	Violates IS 2470 separation rules from structure
6	Six of ten door openings drawn beside wall	Openings floated outside the physical masonry line

The mistakes this prevents on your site

These six defects show how easily visual drawings create expensive site blunders.

In Defect 1, the corridor showed 914 mm on the rough draft. The National Building Code Part 3 requires 914 mm clear width. However, the drafter measured from the outer wall face. Once the 110 mm brick partition was built, clear space dropped to 804 mm. You would lose 110 mm along the busiest walking path in the home.

In Defect 2, two 900 mm doors were placed inside that same corridor. Because the doors started 60 mm inside the corridor edge, the door frames extended past the masonry jamb. The carpenter would have no wall to anchor the frame to.

Defect 3 and Defect 4 show furniture collisions. Our practice rules specify that bedroom wardrobes need 600 mm depth, plus 150 mm clearance for passing doors. The bedroom door swung directly into the wardrobe zone, overlapping by 567 mm. In the bathroom, the door leaf hit the counter by 290 mm. You would either cut the vanity or reinstall the door frame.

Defect 5 positioned the septic tank only 2.6 m from the exterior wall. IS 2470 mandates at least 15 m from the building unless the vent pipe extends 2 m above the roof. Furthermore, Tamil Nadu Combined Development and Building Rules 2019 and IS 2470 mandate 18 m separation from a borewell. The layout now routes drainage directly to the plot corner furthest from the borewell.

Defect 6 revealed that six out of ten doors did not sit inside real walls. In standard construction across India, basic finish costs ₹1,600 to ₹2,000 per sq ft, standard finish costs ₹2,000 to ₹2,800 per sq ft, and premium finish costs ₹2,800 to ₹4,500+ per sq ft. On a 995 sq ft house, basic construction sits around ₹16.9 lakh at ₹1,700 per sq ft. Demolishing brickwork, shifting lintels, and patching plaster to fix six wrong openings wastes thousands of rupees from that budget.

What this means for your plan

Check your concept sketch to ensure every door leaf swings clear of wardrobes, counters, and sanitary fixtures by at least 50 mm. Ask your licensed architect or engineer to confirm that every rough door opening sits fully inside a structural wall before masonry starts. Verify that corridors keep their full 914 mm clear width after accounting for 110 mm partition plaster and masonry. The tool applies every clearance rule and wall check automatically when it draws your plan.

Sources

MEASURED: on our own drawings the checker found 6 of 10 door openings drawn beside their wall rather than in it, after a human review had passed them
PRACTICE: every door opening lies inside a real wall, checked automatically at build time
MEASURED: our own list of six defects found in a set of drawings that had already been read carefully by a person

Want this applied to your own plot, with the numbers checked?

Start your sketch — free

Do a whole-house door pass before you buildDoors are the highest-leverage variable in a plan. Thirty minutes, every door, hinge side and swing, as one exercise. What you can see from the front doorThe view from the entry decides the whole privacy structure of a house. Five things that should never be in it. What the 34 checks actually measureNot a quality claim. A list of measurements taken off the drawing at build time, and what happens when one fails.