The houses with thick walls and flat roofs are formed in Rajasthan.

Explanation:
Rajasthan, the largest state in India, is known for its extreme climatic conditions, with scorching hot temperatures during the summer and cold winters. The traditional houses in Rajasthan are designed to withstand these harsh weather conditions and provide maximum comfort to the residents. One of the key features of these houses is their thick walls and flat roofs.

Thick Walls:
The houses in Rajasthan have thick walls made of locally available materials such as stone, mud, and clay. These thick walls act as natural insulators, helping to maintain a comfortable temperature inside the house. They provide excellent insulation against the heat during summers and keep the interior cool. Similarly, during winters, they help retain the heat inside the house, keeping it warm.

Flat Roofs:
Another distinctive feature of these houses is their flat roofs. The flat roof design is suitable for the arid climate of Rajasthan as it prevents rainwater from accumulating on the roof. The absence of sloping roofs reduces the chances of leakage and damage caused by heavy rainfall. Additionally, the flat roofs can be utilized as additional living spaces or for various purposes such as drying clothes, storage, or recreational activities.

Advantages:
The houses with thick walls and flat roofs offer several advantages in the climate of Rajasthan. Some of these advantages include:

1. Thermal insulation: The thick walls help in maintaining a comfortable temperature inside the house by acting as insulators against extreme heat or cold.

2. Rainwater management: The flat roofs prevent water accumulation and minimize the risk of leakage and structural damage caused by heavy rain.

3. Additional space utilization: The flat roofs provide additional usable space for various purposes, making the most of the limited land area.

4. Cost-effective construction: The locally available materials and traditional construction techniques used in these houses make them relatively affordable compared to modern construction methods.

In conclusion, the houses with thick walls and flat roofs are a traditional architectural feature of Rajasthan, designed to withstand the extreme climatic conditions of the region. These houses provide thermal insulation, effective rainwater management, and additional usable space.