The Stirling-based business completed its largest scheme yet in August, the Aberdeen Exhibition and Conference Centre for developer Henry Boot.
Chairman Bill Robertson said the firm now had the capability to deliver major schemes around the UK.
He said: “We have now firmly established ourselves as a significant niche infrastructure provider who can deliver major projects in excess of £100m.
“Our major projects team now has the capability to undertake significant projects anywhere in the UK.”
This extra workload from major projects lifted staff levels by 15% to over 2,600 employees and generated an 11% rise in pre-tax profit to £21.3m in the year to March 2019.
Robertson Group continued to enjoy strong operating margin which even after slipping back slightly from last year’s peak of 3.2% remained well above industry averages at 3%.
Robertson added that a focus on strong cash management had lifted year-end net cash to over £75m.
He said: “With the current order book we are confidently expecting the coming year to be another successful one.
“Our regional business model will allow us to further expand our geographic coverage, as and when we deem necessary.”
Robertson added that revenue at the FM business grew 50% to £76m after securing several contracts previously held by Carillion, which also boosted headcount at the business to 450 staff.
The group’s strategic asset management arm set up in 2018 to offer council ways of releasing value from land was on course to deliver in the year ahead, he added.
The standalone housing business, Robertson Residential Group, which was hived off as an independent business in 2018, also delivered growth with revenue up 23% to £177m.
During the year the housing business operated from 50 sites achieving 326 completions, up from just over 200 in the previous year.
Expansion of the private homes arm in the north of England made a contribution with further growth expected in coming years.
But in its first year as a completely independent business pre-tax profit nearly halved from just under £12m in 2018 to around £6m last year, due mainly to a challenging year at the partnership homes division.
Robertson said the residential arms was investing in people and had grown its staff from 282 to 325 over the year.