SIPTU has confirmed that workers at a Roadstone Wood quarry facility at Fortunestown in Dublin have downed tools in an unofficial industrial action.
Roadstone Wood is a subsidiary of CRH plc.
The dispute follows the announcement by the company that it intends to close the subsidised staff canteen at the plant.
SIPTU branch organiser Davy Lane said the stoppage involves more than 100 electricians, fitters, truck drivers and general operatives working at the site.
The site has block, sand, quarry and other plants.
He said it does not involve office staff at the nearby CRH headquarters in Belgard Castle.
Mr Lane said that for the past 30 or more years, staff working at the plant have enjoyed a subsidised canteen and anyone who worked on the road received an allowance in lieu of the benefit.
He said the company announced yesterday, that as part of cost-cutting measures, it would be closing the canteen and would buy out the subsidy and allowance.
Mr Lane said this is completely unacceptable to staff because they work in all weathers and are used to getting hot food.
A company proposal to install microwaves for staff to heat their own meals was not acceptable as it would shorten break periods.
Mr Lane said those involved in the dispute say their unofficial action will continue until the matter is resolved.
He said there was a danger of the action spreading to other CRH-owned facilities if it is not resolved.
Mr Lane said there is currently no picket in place.