The figure accounts for almost two thirds of the company's 320-strong work force.
Earlier this week, Patton entered administration due to financial difficulties experienced as a result of the industry downturn.
The administrator, Tom Keenan of Keenan CF, has not confirmed the exact number of layoffs, but said that following recent trading difficulties a number of the company's contracts were terminated by customers, and this has impacted on the level of staff needed.
A statement from the administrator said: "Following an urgent initial review of the Company's trading operations in conjunction with the Directors, unfortunately it has been necessary to make a number of staff redundant as of Friday November 9th.
"The Administratior will continue to review employment in the context of workload and the financial position of the Company and will keep employees informed," they added.
Patton has traded for 100 years and has a total turnover of around £140m.
The Co Antrim firm specialises in house building, fit-out and construction, and posted pre-tax losses of £7m last year.
After speaking to some of the workers outside the Patton offices on Friday, UTV's Business Editor Jamie Delargy said there has been surprise at the rate of redundancies.
"There's a lot of somber-looking individuals going into Patton this morning and emerging, most of them, looking very reluctant to talk," he said.
"One or two have exchanged words that yes, up to 200 are expected to lose their jobs.
"But what is really surprising is the rapidity at which the administrator is running down the scale of the workforce. Normally in these situations there would be a fair amount of time elapsing before redundancies would take place but clearly the administrator feels the position is so dire that they had to act quickly."
In a statement, Employment and Learning Minister Stephen Farry expressed his regret at the redundancies and pledged to do what he can to help those affected get back into work.
"Today my officials are delivering our Redundancy Advice Service on-site to provide employees with information and professional advice about the options and support available to them including employment, self-employment, training and education opportunities and careers advice," said the Alliance minister.
I would like to assure those affected by today's announcement that my Department will be making every effort, along with the Department for Enterprise, Trade and Investment, and the Social Security Agency (SSA) to assist those affected.
Dr Stephen Farry
"Job losses such as those announced today by Pattons are extremely regrettable, not only for those who have been told their jobs are to go, but also for families, communities and the economy as a whole."
North Antrim Sinn Féin MLA Daithí McKay urged Mr Farry and Enterprise Minister Arlene Foster to take immediate action.
"This is a black day for Ballymena, especially in the lead up to Christmas," said the Sinn Féin representative.
"Both the DEL and DETI ministers need to act immediately to ensure that the Patton workers have immediate access to support and advice in regard to finding re-employment and re-training. DETI needs to ensure that support is given by invest NI to construction businesses and those in the supply chain affected.
"While there is a need for a focus on foreign direct investment it should not be to the detriment of our construction firms who also need support."
SDLP Councillor for Ballymena, Declan O'Loan expressed "support and sympathy" to the workforce and Patton family.
"Patton were continuing to search for and obtain contracts and carry those out successfully. But my belief that servicing the debts resulting from previous land purchases was what crippled the company," he said.
"It is a very unfortunate situation but tragically it has to run its course at this stage."
He added: "Once again I hope that the administrator will be able to stabilise some part of the business and give some clarity and hope to the remaining workers and creditors who are owed very large sums of money."