A £3.4m profit from the disposal kept profits in line with 2014 when the Belfast-based family-owed construction group delivered £4.8m.
In the year to March 2015, turnover rose by 28% to £213m, according to latest accounts just posted at Companies House.
Turnover is expected to pass £300m this year after Lagan rescued one of Northern Ireland’s oldest building firms H&J Martin last April.
According to H&J Martin’s most recent accounts also published in December, the former family-owned builder suffered a £4m pre-tax loss in the year ending on the eve of the takeover.
This compounded a £9.6m loss the year before on turnover standing around £100m.
The deal saw Lagan Construction Group’s head count swell from 500 to around 900, prompting plans to expand its Rosemount House head office in Belfast.
The current HQ of H&J Martin on the Ormeau Road will be re-developed at a later stage.