An OPSM notice on the door said the building was "currently closed due to concerns regarding the structural integrity".
Ms Rossiter said WFAT was adamant the building should be knocked down as soon as possible.
"We don't intend to leave it on such a public corner for too long. We definitely expect it to come down in the calendar year."
An initial assessment was carried out on the building in 2010, which found it to be meeting 36 per cent of building standards.
Ms Rossiter described that evaluation as a "desktop assessment", which was carried out in an office and based on historical plans submitted to the council.
After the original assessment, the trust was keen to investigate how much work was needed to bring it up to standard and a thorough second assessment was carried out by an engineering firm. The engineers spent several days inside and outside the building during that assessment.
A third investigation was commissioned by the board in January this year. That evaluation assessed the building at less than 6 per cent compliance.
Ms Rossiter said the massive 30 per cent difference between the first and second assessments was probably due to "discrepancies" between the Academy Building plans and the actual 1960s rebuild after the 1942 earthquake. She said there were some building features which were present in the rebuild plans but had been omitted from the actual rebuild.
"There was extensive damage in the 1942 earthquake," she said. "But the plans and actual construction didn't take place until the 1960s."
Board chairman Graham Edridge said the findings of the report were a concern for everybody.
"We were shocked when the unsigned assessment we received in January 2013 found that the building performance was more like 6 per cent in a moderate earthquake," he said. "Although it is part of Masterton's history, dating back to 1906, there are no affordable strengthening options that would adequately improve the seismic performance of this building."
The WFAT was formed when the Sedgley Family Centre closed and has distributed more than $255,000 to local services for the past three years.
The organisation said it was disappointed the costs of demolishing the building and potentially constructing a new one would tie up capital and make it difficult to support Wairarapa ventures.
Mr Edridge described the news as a "double whammy".
"Many locals throughout Wairarapa have benefited from our support, so this is a double whammy for the community because our ability to provide funding is in jeopardy."
Masterton District Council said it had received no official documentation from WFAT outlining any plans for the demolition of the building and did not wish to comment at this stage.
The Academy Building was first constructed in an Italianate style in 1906 by John Hunter, who was also well known as one of the main contractors involved in the construction of the Wellington Town Hall. Gareth Winter, of the Wairarapa Archive, said that style of architecture was popular at the time. The style originated from a distinct 19th-century phase in the history of Classical architecture.
In the 1960s, the Academy Building was rebuilt. Mr Winter said a lot of central Masterton was "much plainer" after the 1942 earthquake.
The name was not given to the building because of any educational academy but because the original tenants, McLeod and Young, called their bookstore the "Academy". A bookstore was there for about 100 years.
