Health bosses at Lincoln County Hospital say patients are set to benefit from two major projects.
The children's day ward has recently moved from its old site into a new, purpose-built ward block with a playroom and relatives' room.
The vacated space will be refurbished and be used as an extension to the hospital's emergency assessment unit.
Together the projects will cost £1.77m and should be fully up and running by July.
The extension to the EAU will provide 19 trolley bays and beds as well as a new reception area and waiting room.
Sister of the EAU Helen Shelton said: "The additional beds will enable us to provide a prompt nursing and medical assessment for patients being referred to the unit."