The gas maintenance and compliance firms works for local government and social housing sectors in London and the south east of England.
K&T employs over 140 full-time staff and turned over nearly £10m last year making a profit of £1.5m.
Lakehouse, which now turns over more than £100m a year, will widen its service offering with in-house gas compliance and maintenance services, opening up a huge sector of the market.
The gas maintenance specialist provides services to over 43,000 homes throughout London and the south east for clients like East Thames Housing Association,
Greenwich council, Peabody Trust and Poplar Harca Housing Association.
K&T bosses James Day and David Greenfield will remain with the firm as part of the enlarged Lakehouse group.
Stuart Black, chairman of Lakehouse, said: “I am thrilled that we have secured K&T.
Their service offering compliments the Lakehouse offering, and we share a number of key clients, so I am confident that together we will benefit from continued growth and development.”