A digital rendition of luxury condominium Shaa, a joint venture project between Thai developer KPN Land and Singapore developer Keppel Land.

Despite a large condominium supply, the Sukhumvit area remains attractive to buyers, capturing a sales rate of about 70% as of the first quarter of this year, property consultant CBRE Thailand says.

CBRE managing director Aliwassa Pathnadabutr said Sukhumvit has the largest condo supply in downtown Bangkok, with launches totalling 14,000 units as of the first quarter.

"The total condo supply sold in the Sukhumvit areas was high at 10,000 units, which accounted for 69.8%, despite a large amount of supply," she said.

Other locations in downtown Bangkok saw under 6,000 units in new condo supply. The location with the second largest amount of condo supply following Sukhumvit was Silom-Sathon with around 5,700 units.

However, locations in outer Sukhumvit saw the highest sales rate of condos with 88.2% of a total supply of 3,600 units. It was followed by central Lumpini at 84.1%, Silom-Sathon with 82.7% and Pathumwan with 80.6%.

Two other areas, the riverside and Rama III, had a sales rate of 78.6% and 43%, respectively.

As of the fourth quarter last year, the average selling price of a luxury condo was 270,499 baht per square metre, a rise of 15% from the year before.

The riverside had the highest average selling price at 330,000 baht per sq m, followed by central Lumpini with 288,000 baht, Sukhumvit with 262,000 baht and Silom-Sathon with 240,200 baht.

Ms Aliwassa said the higher selling prices of condominiums followed rising land prices.

In 2017, the Lumpini and Ploenchit areas saw the highest annual jump in land prices with 55% from 2016, followed by Sukhumvit with a rise of 30% and Silom-Sathon with 14%.

Last year the Sukhumvit area achieved a record-high land price of 2.6 million baht per sq wah, up from 2 million baht in 2016, she said.

According to market research by CBRE, there were a total of 950 condominium units launched in downtown areas in the first quarter of this year. CBRE expected it would total around 8,000 units by the end of the year, down from 12,544 units in 2017.

Of the first-quarter amount, 762 were in the high-end and luxury segment. The rest were in the upscale segment with none at the middle- to lower-end.

Meanwhile, property developer KPN Land will launch a new luxury condo project on May 25, said chief executive Rawee Tahtniyom.

The project is a joint venture development with Singaporean developer Keppel Land called Shaa.

With a sales value of 2.5 billion baht, the project would be located on a one-rai site on Sukhumvit Soi 19 and comprise a 24-storey tower with 143 units sized 34.25-113.25 sq m and priced at 320,000 baht per sq m on average.

The company targets having 50% of units sold during the launch period and will stage a roadshow in Singapore in July this year to introduce the project there, aiming to sell 30% to foreign buyers.

Sam Moon Thong, president of regional investments at Keppel Land, said investment in the property sector in Thailand is attractive because of the market's potential, particularly in Bangkok, which is benefiting from increasing urbanisation and a growing middle class.

"The economy is improving and investment sentiment becomes more attractive due to political stability and no chaos," he said.

"We are keen to invest more in high-end residential developments in Bangkok, as demand remains high."