Any recommendations for underfloor mixed rads heating design and supply company

[Jeffb]

Hi All , I am in the process of adding a wrap around extension to an existing 50s built house. I am interested if anyone can recommend an underfloor heating supplier who designs the system . I am looking to put underfloor heating on the new block an beam ground floor area approx 100m2 then radiators on the second floor approx 50m2 2 beds and en-suites and radiators in the existing 3 bed house both floors approx 80m2. I will also have electric heating in the bedrooms via Solar and battery storage probably?we can install the system I have a relative who can do the gas work , but not very experienced in designing systems.

thanks in advance for your help .jeff