Thailand uses its own set of measurements of area and here is a table of those areas, with the equivalent metric measurements for comparison:
|1 Talang Wah
|1 square Wah
|100 Talang Wah
In the picture above, the red outlined plot near the road is approximately 1 Rai, and the larger outlined plot below is over 2.5 Rai. The 1 Rai plot is where the Thai House will be built.