For interpreting a horoscope in Vaastu terms, certain guidelines are necessary. Astroshastra presents here some basic rules, which are very useful in Astro-Vaastu analysis.
Experienced astrologers can derive other subtle rules applicable to Vaastu situations, based on this logical pattern.
1. Powerful position of the first house owner in a horoscope indicates that the Vaastu is having good ventilation and entry or openings are from the east direction. Hence, both
the person and the Vaastu can be predicted to be benefiting from qualities relating to intelligence, personality, social status, and physical form.
2. Saturn in the 7th house indicates that it is powerful as far as its directional status is concerned. The Saturn in the 7th house bestows a full-moon-day effect on the planets
in the 1st house. Naturally, planets in the first house with their ownership over specific houses and directions will have good effects, both for the horoscope and the Vaastu.
Person with such a horoscope will have slopes towards the east in his Vaastu- kshetra (plot) and the West openings will be closed implying good effects of the East direction for
vaastu. On the other hand, any evil effect of Saturn on the first house lead to the following inferences west entry for the Vaastu, ventilation from the west, staircase and/or
toilets in the east, the east direction completely blocked etc.
3. Presence of papgraha' in the 4th house and incorrect position of owner of the 4th house indicates that the Vaastu of such a person may have the following deficiencies;
toilets to the north,
staircase to the north,
blocked north direction,
entry from the south direction,
House with north-south axis shorter than east-west axis.
4. Owner of the 1st house in the 12th, 8th, or the 6th house implies that map axis will not match with the geometric axis of the house.
5. Owner of the 7th house placed in the 6th or 12th house and inauspicious planetary position for the 7th house is indicative of the following flaws in the Vaastu;
underground water tank located in the west zone,
ground slopes towards the west,
open terraces on the west side,
blocked east direction,
entrance from the west,
substantial ventilation from the west direction.
6. Owner of the 10th house in undesired position and l0th house clubbed with incorrect planetary positions preordain the following Vaastu-doshas;
either the plot or the construction is of 'Vyaghra-Mukh' type,
excessive low levels on the south and south-west sides,
more side margins on the south side,
entrance from the south direction,
distortions in the qualities of the north direction.
7. Incorrect placement of Moon and its association with 'Papgraha' indicates misplaced north of the Vaastu.
8. Incorrect location of Sun subjected to attack by Saturn spells severe Vaastu-dosha in the south direction.
9. Kal-sarpa horoscope may point towards various Vaastu doshas with severe consequences.
10. Comparing the characteristics of a Vaastu and horoscope of the dweller is one of the better means to judge the accuracy of a given horoscope.
There is a definite correlation between the zodiac signs and ruling planets of these signs. The degree of inter-planetary friendship or enmity originates from the characteristics
of five great elements, which are associated with various constellations and planets.