The Waikouaiti Coast Heritage Trust has been selling firewood since December to raise funds for a new museum and information site.
The total amount raised so far was ''in excess of $20,000''.
Trust president Bill Lang said they could not keep up with demand.
At the height of sales, they had 26 volunteers helping to cut, load and deliver firewood.
He was expecting to handle between 600 and 800 cubic metres of wood by the time the fundraiser was complete.
''It was just an idea over a beer,'' Mr Lang said.
''We don't even know how far it's going. It just keeps on generating money.''
Most of the wood sold had been given by local farmers.
The Dunedin City Council had also contributed.
The demand was put down to the colder winter and people stockpiling for next winter, he said.
The venture had created a real sense of community.
''We've got an enthusiastic group of people.
''It's community-based; it's donated material.
''It's an old-fashioned community fundraiser,'' he said.
''When the group's around, there's a very good buzzy thing going on.''
Mr Lang said the new building was ''actually quite sexy'' and hoped it would be completed by the end of next year.
