A blaze spread to the roof of the Europa Pools leisure centre after ivy on its walls caught fire in the searing temperatures.
Two fire engines were called to the Birkenhead swimming pool and gym just after 4.30pm on Wednesday.
Firefighters at the scene then requested another “aerial appliance” vehicle with a larger ladder to help tackle the blaze.
A fire service spokeswoman said they were dealing with a fire involving external foliage that had then spread to the fascia boards of the roof.
The fire comes after temperatures climbed above the mid-20s for the second day in a row.
Firefighters requested the incident investigation team establish the cause of the blaze.
Original source: Liverpool Echo