The Scottish building standards system differs in form and terminology from legislation and regulation in the rest of the UK.
For one thing, the regime is pre-emptive, meaning that no work should start on site until a building warrant has been issued. This can be granted in stages and amended as works continue, or as an unstaged warrant where all design information is available upfront.
A common misconception is that these stages reflect the different phases of construction. While that is usually the case – a stage 1 application typically being foundations and drainage – the staging will reflect the outcome of discussion and agreement between the verifier and the applicant or their agents.
Such staging can also allow the certifier to include a schedule as part of the certificate of design that defers assessment of specific contractor-designed elements, where the relevant specialists' information is not available at the time of application.
Once a building warrant is applied for, the verifier – the organisation appointed by the Scottish government to carry out the building standards function – will undertake what guidance refers to as 'detailed technical checks' to determine whether it can grant the warrant and allow construction to start.
Currently, only the 32 Scottish local authorities can act as verifiers. The verifier undertakes a risk-based analysis, aimed at identifying either non-compliance or a lack of evidence of compliance.
Building regulation is a devolved matter. The Building (Scotland) Act 2003 gives Holyrood powers to make regulations, while The Building (Scotland) Regulations 2004 define the performance criteria that construction work must meet. Below these sit the technical standards and supplementary guidance.
This hierarchy means that changes to the regulatory system are relatively straightforward, with any necessary revision made to guidance rather than the standards themselves and thus avoiding the need for parliamentary time. In practice, of course, the process of reviewing, developing, adopting and then enacting changes still requires consultation and research, which can take some time.
This is perhaps inevitable, given that raising performance thresholds – however justifiable – is disruptive. The construction industry and the regulatory framework have to balance life safety issues with the critical need to reduce carbon emissions, while also being able to plan affordable projects to meet demand for housing.
The process of developing the technical standards is also relatively straightforward. To do so, ministers at Holyrood must be aware of an issue that can be regulated; this issue must be significant enough to justify regulation, and that regulation must be proportionate and enforceable.
Having sat on working groups for the Building Standards Division (BSD) of the Scottish government over the years, however, I know that drafting the wording of technical standards is considerably more nuanced. They must be read in the round because, while one standard or clause may seem to allow blanket adoption of a construction methodology or services installation, others will restrict their use where appropriate.
Specific clauses in the technical standards generally appear first as guidance that applicants should consider. This guidance is formally published, with a baseline threshold for compliance. Over time, this threshold is raised as the construction industry builds capacity to address the underlying issue.
A good example of this development process has been the introduction of guidance, which requires that one in 20 new dwellings are tested for airtightness. This requirement subsequently became universal in February 2023.
This process first raised awareness of the impact of airtightness on the energy performance of buildings. The random sampling then focused attention on detailing and the quality of work while allowing the industry to develop the capacity to test all new buildings affordably, knowing that the Scottish government had committed to this requirement becoming universal.
The building warrant process is a risk-based permit system. The verifier takes on no liability, and in granting a warrant simply affirms that they have not identified any non-compliance. Should non-compliance come to light later in the process it remains the building owner's responsibility to resolve it.
Compliance is based on meeting the mandatory standards in the regulations. Generally, applicants follow BSD guidance to do this; but they are not obliged to do so and can justify their designs by referring to other guidance, such as BS 7974:2019 Application of fire safety engineering principles to the design of buildings. Code of Practice.
Any alternative approach would have to be assessed by the verifier all the same, to confirm compliance with the mandatory standards.
It is just as important to note what the building warrant process does not guarantee, though. From a design rather than a regulatory perspective, following the guidance does not guarantee that any proposals meet the client's detailed needs or brief; or that buildings are well constructed, or even compliant.
For instance, the client may have asked for a new home for their growing family, but room layout may mean that, in reality, different spaces are poorly connected and there is little in the way of externals views, while the plan of the house doesn’t easily allow for a future extension.
Similarly, new structural walls may be sound but poorly plastered and decorated. As an indicator of poor-quality work, the latter might well prompt closer scrutiny from the verifier but would not in itself be a reason to refuse to accept a completion certificate.
'Following guidance does not guarantee that proposals meet the client's detailed needs or brief; or that buildings are well constructed, or even compliant'
In Scotland, the skills and specialist knowledge of designers and contractors can be recognised through the certification of design or construction, and the opportunity to provide certification schemes lies with the construction industry itself. Any industry body can make a case to the Scottish government that a new scheme should exist and that they wish to provide it.
The schemes currently operating are as follows.
Scheme providers are appointed by the Scottish government, and are subject to regular audit to demonstrate that they follow government guidance as well as their own detailed procedures.
Each certificate is issued by an approved body registered with the relevant scheme. The approved body might be a limited company, partnership or sole trader, and it guarantees that the design or installation complies with the relevant mandatory standards. The certificate must be accepted by the verifier as conclusive evidence of compliance.
To be registered, approved bodies must demonstrate that they have suitable insurance in place and meet the requirements of their scheme provider. Such requirements include appointing one individual as an approved certifier of design or construction, and another as a certification coordinator. The latter is the point of contact between the scheme and the approved body.
The same individual can be appointed as both a certification coordinator and a certifier and, in the case of a sole trader, may be the approved body as well. In other circumstances an approved body may have multiple approved certifiers, while approved certifiers themselves can be employed by multiple approved bodies. The certification coordinator may also have a deputy to cover extended periods of absence.
Each approved certifier must demonstrate that they meet the threshold of competency set by the scheme provider in its agreement with the Scottish government, and maintain this through annual CPD.
The certifier has the competency to assess compliance, while the approved body is the contracting entity providing the certificate. To be valid, a certificate must be signed by both the certification coordinator and the certifier. That certificate is registered with their scheme provider and issued to the verifier on behalf of the applicant.
Certification procedures, competency and CPD are subject to audit by the scheme provider. The approved body must work within a defined quality assurance framework and keep detailed record of its certification activity for a minimum of 25 years.
'Certification scheme providers are appointed by the Scottish government, and are subject to regular audit'
Certifiers generally have a greater role than verifiers in a project. They are likely to have been tasked with optimising the proposed design or installation to meet specific client requirements, such as enhanced energy performance.
Applicants for building warrants have a space on the form to indicate their intention to submit a certificate of design. When they do so, they receive a discount on their application fee, while the verifier is in turn relieved of the requirement to carry out necessary checks on that area of design. However, the warrant is not granted until the certificate is submitted.
Similarly, warrant application forms can record the intention to submit a certificate of construction on completion. Again, the applicant receives a discount, while the verifier need not undertake reasonable enquiry into the relevant construction elements on site and will not accept a completion certificate until the relevant certificate of construction is submitted.
The establishment of certification schemes is in part a response to the ever more complex challenges that the built environment has to address, such as climate change.
In my second article, I will look at the particular process of demonstrating compliance with section 6 of the technical standards, dealing with energy, and look at the prospect of a proposed Scottish Passivhaus Equivalent standard.
BUILT ENVIRONMENT JOURNAL
Dr Wojciech Mrozik 03 September 2024
BUILT ENVIRONMENT JOURNAL
John Askew MRICS 20 August 2024
