Penarth Library has secured Welsh Government funding to refurbish its first floor.
The Stanwell Road library is planning to improve its local history collection and modernise community spaces for study, co-working and meetings.
The refurb will cost just over £87,000 to complete - with ministers providing a grant of nearly £78,500 for the project.
In all, six public libraries, three museums and two archives across Wales will share £1.8m of funding to improve cultural facilities and library services.
The Welsh Government says the money supports its commitment to promote cultural institutions.
Culture minister Jack Sargeant said: "Cultural services across Wales provide vital spaces for communities to learn, connect, and engage with our rich heritage. This £1.8m investment will help transform these services to be greener, accessible, and responsive to local needs."
“Programmes like these have, and continue to be, a vital way for our cultural assets to ensure their services are fit for purpose, modern and that their delivery can become more sustainable.”
Among the other projects, Glamorgan Archives in Cardiff will get £70,000 this year and an extra £244,000 next year to spend on environmental sustainability.

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