At Greaves Slate Company, the recession has already led to 40 redundancies. Times are hard and are about to get worse. While the company can boast prestigious roofing contracts for Kensington Palace and the Royal Courts of Justice in London, local roofing work has historically provided the foundation of the company's business.
Snowdonia National Park had resisted the use of cheap imported slates, particularly from Spain, but the EU has forced the Welsh-only policy to be abandoned, ruling it to be anti- ompetitive. In Aberdovey, the first Spanish slate roof is being carefully monitored for durability. Alan Jones, chief officer of the National Park, said there had been disappointment at the enforced change in the planning regulations.
"We would have liked to continue to support the Welsh slate mining industry," he said. "We think there is nothing better for local roofs. Local slate has been used for hundreds of years and survives the weather conditions here."
He said the National Park would be closely monitoring the foreign slates to see how they weathered. If the slates deteriorate, the roof could be replaced with native Welsh slate.
Arthur Thomas, director of Greaves and manager of the Llechwedd mines, which have been operating since 1836, shows a press cutting detailing how a Spanish slate roof on a London shopping centre had to be replaced. His company had tendered for the renewal work.
But he fears the use of Spanish slates - priced at nearly half of their Welsh equivalent - will damage the reputation of all slate and harm producers. His company is one of two in Blaenau Ffestiniog, and three in the region, producing roofing slates in the traditional way.
After being blasted, the huge chunks of slate are sawn, then split by hand and trimmed. Only the use of massive dumper trucks for transporting from the quarry has made the task easier in recent years. "It is hard times at the moment and the EC ruling cannot help," said Mr Thomas. "The problem is it is not fair competition. The quality of slates we produce and our overheads are not the same as in Spain. There are container loads of Spanish slate arriving in this country every week."
He said Snowdonia National Park had played a big part in maintaining the local industry and the use of Welsh slate had been an important "shop window" for local producers.
The peak for the industry was in the 1920s when there more than 12 mines and quarries. Llechwedd employed 750 then. It now has 230 workers, a figure that includes staff in the tourist section of the mine, which is an important sideline.
Mr Thomas said: "Every order we get has to be fought for. We are surviving at the moment, but if you ask me whether we will be here in the future, I don't know."