Lancaster Library has closed to the public so work can take place on the building's heating in the cold weather.
Planned works are taking place on a new heating system at the library in Market Square.
Contractors had originally been working at night so the library could remain open.
Temporary heaters were in place at the library, but they have stopped being effective in the current cold weather in keeping the building to an acceptable temperature.
So Lancashire County Council, who run the library, decided to close the building on Monday for a short period so the work could be completed.
Tests will be carried out today (December 14) on the new system and it is hoped the library won't be closed for much longer.
A Lancashire County Council spokesman said: "Lancaster Library is currently closed due to essential building works related to the building's heating system.
"Your nearest library is Morecambe, which will have extended opening hours and will be open from 9am on Tuesday and until 5pm on Wednesday this week.
"We are sorry for any inconvenience this may cause."
Lancaster Library has been designated as a 'Lancashire warm space' during the current cold weather.


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