[Tony]

This may be of interest use too. Not 100% whether the Defective Premises Act of 1972 applies in Scotland:

Legal position of owners of defective homes
2.6.When considering the context in which reference services are provided it is obviously important to have regard to the protection that the law affords the purchaser of a new home which turns out to have structural defects.
2.7. The legal position at common law is clearest if the original owner of the defective home has a direct contractual relationship with those responsible for the defect, whether they be builders or architects. The terms of the contract will usually provide adequate protection for the owner although, as with any legal remedy, it will only ultimately be of value if those responsible for the defects are still available to be sued and are not, for example, insolvent. In the absence of express provisions, terms will be implied requiring
the dwelling to be constructed in a good and workmanlike manner and to be fit for human habitation. At common law, however, any subsequent purchaser of the home will only have a contractual remedy if it has been agreed that the original purchaser's rights can be assigned to him.
2.8. The inadequacies of the common law to protect subsequent purchasers of new homes led to the enactment of the Defective Premises Act 1972. Section 1 of the Act imposes a statutory duty on builders, developers, subcontractors, architects and others who take on work providing a dwelling to see that the work is carried out in a workmanlike manner, built with proper materials, and that the dwelling will be fit for habitation when completed. Although the statutory duty of care provided by the Act overlaps the common law duties, it improves the position of the second and subsequent purchasers of the new home,
and cannot be excluded by any exemption clause in the contract. On the other hand, the limitation period of six years for making a claim runs from the date when the home was completed, not from a later date when the defect was discovered.

From the Competition Commission website - http://www.competition-commission.or...text/299c2.pdf