Hong Kong's construction workers will get pay rises of up to 12.5 percent after a three-year freeze, a union announced on Wednesday, although it cautioned that the increase won't be enough to fill a labour shortfall in the industry.

The Hong Kong Construction Industry Employees General Union announced the new minimum pay scales after talks with members, contractors' groups and others in the sector.

Plasterers will see pay increase by 12.5 percent while installers of false ceilings will get 12 percent and metal and marble workers will see pay increases of 7.7 percent. Other workers will get pay rises of at least 3 percent, though bar benders and concrete and excavation workers will continue to see their wages frozen.

The union's chairman, Wong Ping, said the pay increases were "mild" and "not ideal", but acknowledged that employers cannot pay higher salaries as they have to stick to budgets that are based on tenders won years ago.

Yet Wong said the pay rise alone would not be enough to attract workers to the sector, adding that labour was in short supply after construction activity surged as the pandemic eased.

The union also called on the government to set standards for developers on the timescale for construction projects, saying a survey of members had found strong backing for the idea as a way of easing pressure to complete work quickly.

The group said it questioned 1,470 members in August and September on the matter and found that 83 percent backed the call.

“A few years ago, developers required us to construct a storey in six or seven days. But now they require us to complete it in three or four days,” said Ho Ping-tak, the union's conference development officer.

“The construction period is not reasonable. When workers plateau, accidents occur easily.”

As an example of the pressure workers were under, Tak cited an industrial accident in Yau Tong in August when work continued after the typhoon signal No 3 was issued. Three workers were injured.