Culture Vannin's submitted a planning application for a redevelopment of its headquarters in St John's.
Chair Chris Thomas says the work will tackle essential maintenance issues and improve energy efficiency.
The plans for Fairfield House also involve adding an extension and outdoor exhibition spaces.
The cultural organisation says it'll be paid for from a reserve fund, as well as donations and grants.
Nominations open for 10 local authority by-elections
MHK wants answers on support for home-schooled children
Weather warning for tonight and tomorrow
Mountain Railway damaged by gales
Ten local authorities looking for members in December elections
Don't sweat Met threat on internet
Commissioners unveil mission statement for parish