Is zakat obligatory on money allocated for building a house in stages on land that has been purchased?

There is no zakat on a house designated for residence. As for money, zakat is obligatory on it if it reaches the nisab (the equivalent of 85 grams of gold or 595 grams of silver) and one lunar year has passed over it. The amount of zakat is 2.5%. If one buys land with money after the year has passed, zakat is obligatory on the full amount. However, if one buys before the year has passed, zakat is obligatory on the remaining amount if it does not fall below the nisab. If the purpose of buying the land is for personal use (acquisition), there is no zakat on it. But if it is for trade, zakat is obligatory on it.