Building and civil engineering firm Ritchie Brothers (Scotland) is in liquidation while the partnership of James Scott Builders & Company has been declared bankrupt.
There have been a small number of redundancies at each firm but there is expected to be a wider impact on sub-contractors and local suppliers.
The latest Scottish Construction Monitor showed confidence in the sector has dipped to levels last seen in 2010 and The Scottish Building Federation (SBF) is warning these latest job losses are unlikely to be the last.
Michael Levack, SBF chief executive, said: "A rising tide of firms in the Scottish construction sector are struggling to survive as the long overdue signs of economic recovery fail to materialise.
"Our latest membership survey shows industry confidence continuing to decline. That gives me reason to fear that we will be in for more business failures and job losses in the months ahead."
Graeme Ogilvy, Scotland director for ConstructionSkills, said: "Many of these companies employ local tradesmen and tradeswomen and so the knock-on effect of such companies ceasing to trade has a massive impact on the local economy."
Ritchie Brothers, based at Seafield in West Lothian, has been operating since 1948 and is a third generation family business. As recently as 2010 it had turnover of close to £5 million and employed dozens of permanent staff and sub-contractors.
However, a dispute over a public sector contract coupled with a downturn in trading led the directors to put the company into liquidation.
Donald McNaught, director of insolvency at Johnston Carmichael in Glasgow, has been appointed interim liquidator and said: "The economic downturn has been affecting business generally and the company also had a dispute on a major public sector contract. As liquidator I will be revisiting that and will be trying to negotiate a settlement with that debtor.
"We are still gathering information but I would like to think the creditors will receive a good sum of money back but it is dependent on how much we can recover from these contract collections."
The biggest creditor is understood to be the Ritchie family through their other business Ritchie Brothers Holdings.
James Scott Builders, with its headquarters in Newton Stewart, Dumfries and Galloway, controlled a portfolio of 67 residential and commercial properties from which it took around £264,000 of annual rental income.
But the conclusion of a long-running dispute over building work on a retirement home in South Ayrshire for a wealthy couple from Guernsey has tipped the business into insolvency.
According to Matt Henderson from Johnston Carmichael, who has been appointed to liquidate the assets of the business, James Scott was left facing a claim of more than £800,000.
Its property portfolio has been on the market for several months to try to free up capital ahead of the judgment, but has failed to find a buyer.
Mr Henderson added: "It is an indicator of how hard things have been in the construction and property development sectors. In previous years it could have sold a couple of properties and met that obligation."
Last week 130 jobs were lost when WH Brown in Dundee was placed in receivership.
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