The sustainability of social housing dwellings is tackled more efficiently with an integrated contract than with a traditional tender. In his comparative analysis, PhD candidate Baldiri Salcedo Rahola shows that 'design-build-maintenance' contracts provide the highest energy savings.
For some time the Dutch construction sector has been using integrated contracts in complex infrastructure projects, but lately these contracts have been showing up elsewhere too. Baldiri Salcedo Rahola finds that, when it comes to large renovations, this approach is spot on. “An integrated contract in which the contractor is also responsible for maintenance ensures healthy collaboration and promotes involvement. A contractor will be even more motivated to deliver good work as they will be punished in the maintenance phase otherwise. You’ll find that the objectives will rise as well as the results.”
Salcedo Rahola compared the renovation projects of five social housing organizations in four EU countries and offered questionnaires to 36 corporations from eight EU countries. Furthermore, Rahola interviewed several energy renovation experts from ten EU countries. Based on his findings, he identified four different methods of approach: repeated smaller renovations, the traditional design-bid-build method, design-build and design-build-maintenance. Traditional forms of contract types are found in the United Kingdom, Belgium and Italy in particular, while in The Netherlands and France integrated contacts are starting to emerge. Both countries have relatively large social housing dwellings that need to be maintained and preserved. Dutch corporations in particular struggle with lower budgets and tighter regulations. This is why inventiveness is needed to assemble the improvement program. Sometimes this leads to surprising constructions. For example, Salcedo Rahola encountered a project in Oss where a corporation managed to get solar panels on the roofs. The social housing corporation itself did not have the money for it. The building firm with which they entered into a DBM-agreement on renovation and preservation therefore founded an ESCo. The Energy Service Company retains ownership of the panels, where the corporation pays rent for their use.
When tendering DB-contracts and DBM-contracts, The Netherlands has the advantage against France that most of its corporations are privatized. Because of the privatization, the rules for public procurement are not as strict. Dutch social housing corporations are able to select several parties in a very early stage to open dialogue and bring about the ideal contract. This leads to extensive knowledge and a clear formulation of the common goals. For example, it is possible to make agreements on performance requirements in respect to the anticipated energy savings. This knowledge can furthermore be used for the realization of smarter floor plans and other measures to improve renting. “This intensive collaboration delivers innovation(s) and ensures competition on quality rather than price,” concludes Rahola. “You cannot achieve these results through traditional tenders.”