Last year, the Consumers Association of Singapore (Case), received 1,488 complaints against contractors,up from 1,313, in 2010.
Going by a ranking of industries compiled by Case, contractors were ranked second as the most-complained about last year.
Executive director of Case, Mr Seah Seng Choon, told The New Paper that the complaints were generally about defective work, poor workmanship, delayed delivery and failure to honour terms stated in contracts.
He said: "Each case is unique in its circumstances and disputes may arise due to the difference in expectations and poor communication. We advise consumers based on the facts of the case."
Mr Sky Tan, 36, vice-president of the Singapore Renovation Contractors and Material Suppliers Association (RCMA), felt the surge in the number of complaints could be due to the growing industry, which is also getting more competitive.
RCMA is a non-profit organisation which works at improving the quality and standard of the construction and materials supply sector.
Mr Tan, who runs renovation firm, Sky Creation Design, said: "Consumers and contractors should avoid verbal agreements.
"Every work that is required should be written down, together with the price, in a contract, that both parties have to abide by.
"Verbal agreements always result in disputes."
In the mediation sessions that Mr Tan has handled, he found that generally consumers are unaware of the market standards of workmanship.
Many seek perfect workmanship, which is impossible. Mr Tan explained: "For example, when you have a joint-laminate, there will be a visible line showing the joints.
"I have had consumers complaining to me about poor workmanship when they see the line, when in fact, it is a characteristic of the material used.
"Contractors, on the other hand, should have explained that to their customers."
Mr Tan has seen his share of unreasonable clients and dodgy practitioners.
He said of clients: "There are clients who like to ask for freebies, like microwave, oven and extra cabinets, halfway through the renovation works.
"Some of them will also criticise their contractors' poor workmanship and use that as an excuse to get a discount in the fees."
This article was first published in The New Paper.