Also known asbrahm nabhibrahmanabhicenter of house
The centre of a regular plot is where its two diagonals cross. For an irregular plot, use the geometric centre in AutoCAD, CorelDraw or an image editing tool, or the manual method of hanging a paper cut-out of the plan from a pin.
Centre of the plot or constructed area
The plot is divided into Brahma, Dev, Manushya and Pishach bhoomi by measuring the line from the centre to every corner and marking 0.333, 0.555 and 0.777 of its length. Joining the matching points gives four bands that follow the real shape of the plot.
Whole plot, from its centre to each corner
In the 81 pad (9 x 9) Vastu mandala the ati marma are found by drawing six lines between pairs of outer devtas: the two corner diagonals and two lines parallel to each of them. Their nine crossing points are the ati marma.
Whole plot; the crossings fall mostly in and around the Brahmasthan
Yes, it is wrong. Even if the floors slope to the North-East, a roof whose whole slope falls into the Brahmasthan creates the same defect as a slope toward the centre.
Each floor is judged from its own base: a ground floor from its foundation, a first floor from the floor it stands on. Construction built out over chhajjas becomes part of that floor, and the centre of every floor changes with its own carpet area. If one family uses all the floors, the ground floor shape is the full shape, and a smaller upper floor, such as 25 x 25 over a 50 x 50 ground floor, does not make the plot cut.
Take the constructed area. For the boundary wall gate the centre of the whole plot is used, and for the main door the centre of the constructed area; this is taught in planning.
A sunken courtyard in the centre suits only a temple. In homes the courtyards were actually built raised, with a boundary all around and a tulsi platform in the middle, so they were not counted as a defect.
Keeping it open on all floors is excellent. If that is not possible, a double height open at the Brahmasthan, for example about 20 ft, still balances the space element even if it is closed above. A survey found that houses with a double height at the Brahmasthan had more happiness and peace.
Do not stay in the Brahmasthan at any cost; sleeping in the drawing room, or even on the road, would be better. If zoning the whole area puts the room in the North-East, it can be used with discretion, but it is not ideal; the best zone for a delivery is the South-West, the zone of stability. A backyard on the North side is good.
Either remove the toilet, which is rarely practical, or keep the two flats separate through kilan: four copper nails at the corners of one flat and four at the corners of the other. At griha pravesh a raksha sutra is tied around the house and nails are fixed at the four corners so that the current moves along them, and kilan divides the current the same way. Even on the third floor, simply drill and fix 1.5-inch copper nails.
In the 81 pad grid the line from the centre to a corner is 4.5 boxes long. From the centre, Brahma bhoomi ends at 1.5 boxes, Dev bhoomi at 2.5 and Manushya bhoomi at 3.5, and Pishach bhoomi runs to 4.5. Dividing by 4.5 gives 0.333, 0.555 and 0.777, which are applied to the real length of each centre-to-corner line on the map.
Because in a regular, proportionate plot almost all nine ati marma fall in the Brahmasthan. So an aangan (courtyard) or open space was left there, or the area was kept free of regular stable activity and heavy items. In an irregular plot there is no guarantee where the points fall.
In today's 81-pada vastu the manushya and dev bhoomi are combined, so only three divisions remain: the pishach bhoomi with the 32 outer devtas, the combined manushya-dev bhoomi with 12 devtas, and the brahma bhoomi with Brahma. After dividing the plan with the 0.33, 0.55 and 0.77 multipliers, erase the middle line between manushya and dev bhoomi, since it is not needed for placing the devtas.
Take the centre of the whole plot and map the devtas on it; all the open land around the house, even outside the building, becomes space for the devtas. This is why big houses abroad, as in America, are so balanced: about 4,000 sq ft is built on about 40,000 sq ft of land, so the 32 outer devtas get a huge, open pishach bhoomi and the manushya and dev bhoomi get cross ventilation from all sides. Just as a person given two acres of land enjoys the space, the devtas are pleased by big open land.
Remove the kitchen from the Brahmasthan completely. A kitchen in the Brahmasthan causes division (vibhajan), as if the house were split in two. For the same reason the kitchen platform should not be made in the centre of the kitchen either.