Campaigners for an inquiry into Dumfries and Galloway Housing Partnership's £77 million public contract with failing builder R&D Construction have criticised the Scottish ­Housing Regulator for claiming to have received no complaints from tenants about poor building standards on houses built prior to R&D's collapse.

The regulator's chief executive, Michael Cameron, was quizzed by the Scottish Parliament's infrastructure and capital investment committee last week about the regulator's hands-off treatment of Dumfries and Galloway Housing Partnership (DGHP), which awarded a contract in 2009 to the heavily indebted R&D Construction without seeking standard bank references or guarantees.

The builder - which also had an "above average" credit-risk rating at the time of the award - went into administration in April 2011, leaving discontented tenants, laid-off workers and unpaid local tradesmen, some of whom went out of business as a result.

Asked by SNP South Scotland MSP Joan McAlpine why the regulator had not responded to tenant complaints about R&D-built houses, Cameron said: "We have received no complaints from tenants of the houses involved in the situation with DGHP. We have engaged with the association in response to the [Sunday Herald] coverage, and we have received appropriate assurances. There is not a regulatory issue here for us to become involved in."

However, this newspaper has seen emailed complaints from ­September 2012 from Stephen Reay, a DGHP tenant in Stranraer whose daughter lives in an R&D-built DGHP house.

Reay's email relates the collapse of R&D to "serious problems" with DGHP properties, also referring to comments by local MP Russell Brown - who himself complained to the regulator about DGHP in 2010 - over R&D's allocation of resources prior to collapse. One of Reay's 2012 emails relates the experience of fellow tenants with "snagging problems, the flooding [and] the main regeneration contractor going bust, the main repairs contractor doing the same".

McAlpine said: "I am concerned that the housing regulator does not appear to have told the whole truth to the infrastructure committee …

"Any inaccurate information given to the Scottish Parliament is a ­serious matter, but in the case of the Scottish Housing Regulator this is especially the case, as the regulator is not accountable to ministers but to the Scottish Parliament alone."

A spokesman for the regulator said Cameron's statement was "factually accurate" on the grounds that the whistleblower's own DGHP-owned property, unlike his daughter's, was not built by R&D.

Dumfries Trades Union Council (DTUC) will tomorrow launch a petition to the Scottish Parliament, calling on MSPs to "investigate all the circumstances surrounding the awarding in April 2009 of a £77m contract by Dumfries and Galloway Housing Partnership for housing repairs and housing development in Dumfries and Stranraer to the now defunct building company, R&D Construction Ltd".

In what the DTUC said was a ­reference to the actions and non-actions of the Scottish Housing Regulator - which allowed DGHP to appoint its own "internal auditors" to investigate its actions - the statement added: "We also request the P­arliament to conduct a full investigation into associated allegations of cover-ups in relation to the above contract."

Chaired by DTUC chairwoman Ann Farrell of Unite, the event will feature presentations by Stranraer and North Rhins councillor Willie Scobie and Roland Chaplain, former vice-chairman of Dumfries and Galloway Small Communities Housing Trust.

Several hundred subcontractors plus many ex-R&D employees are listed among more than 550 creditors - the DTUC's statement said they "have little hope of seeing any of the total £8.3m due to them".

The SHR has declined to specify whether its guidelines permit social landlords to award major contracts without conducting bank checks on the financial sustainability of the contractor, as happened in this case.

It said: "There are a number of different arrangements ­landlords can put in place to protect themselves against financial risks in construction contracts."