The Castleford-based firm said it expects to see no material impact from the collapse of Carillion.
PTSG had around £1m of work annually with Carillion and this work is now being taken on by existing PTSG clients. PTSG has taken a £300,000 hit from Carillion's collapse and this has been fully provided for in the 2017 balance sheet.
PTSG's chief executive Paul Teasdale said: "We did a lot of work with Carillion, but it doesn't impact on our work as someone else has to do that work. Some of the insulation projects have been taken on by other companies.
"We don't see any impact on full year volumes."
In fact the redistribution of Carillion's work could be good for PTSG as it has spread the work among a large number of companies.
"Carillion was a very difficult client to work with," said Mr Teasdale.
"They were very demanding and wanted everything done quickly. They did not have a reputation as very good payers."
He was speaking as PTSG, which is the UK’s leading provider of facade access and fall arrest equipment services, lightning protection and electrical testing, announced strong results for the year to December 31.
Group revenue rose 35 per cent to £52.9m and the group saw strong underlying organic revenue growth of 11 per cent.
Adjusted operating profit also rose 35 per cent to £10.6m and adjusted pre-tax profit was up 36 per cent to £10.2m.
The group has raised the final dividend by 14 per cent to 0.80p.
Three acquisitions were completed last year and the group said all are performing well. Nimbus has been fully integrated and the integration of Best is 90 per cent complete. UK Sprinklers has been fully integrated and its trading is 50 per cent ahead of when PTSG bought the business with a strong order book and pipeline.
PTSG has its eye on another 15 possible acquisitions and is hoping to do two or three deals this year with fire protection a key growth area.
The company is seeing strong repeat custom and its renewal rate has increased to 88 per cent.
"This is one of the most important indicators," said Mr Teasdale.
"Customers are remaining with us because they like what we do. Our customers vote with their feet. It's a large endorsement of our business as a whole."
The group said 2018 trading has started well.
Analyst Julian Cater at Numis said: "PTSG's 2017 results demonstrate strong growth (organic and acquired) and consistently high margins.
"Having increased our 2018-19 forecasts significantly with the January trading update we leave them unchanged.
"However, management indicates that trading in 2018 has started well, and we are confident that strong underlying growth, coupled with further bolt-on M&A will drive further EPS upgrades during 2018. We retain our 'buy' recommendation and and 220p target price."