David Miller Architects (DMA) is a practice that has an industry-leading reputation for developing innovative, technology-led solutions. We first featured them on the NBS website in 2012, when telling the story of BIM from the point of view of a small practice. In 2017, we then looked at how they were using standardised manufacturer objects for repeat housing work.

In 2019, DMA has been using NBS Chorus on a number of projects. This article describes how they have found the new specification platform.


Chorus was chosen for a school project, and also to create a standard specification for a set of housing projects for the same client.

As Chorus is a cloud platform, all team members contributing to the specification were added to the system. This allowed for the pairing of experienced specification consultants with designers to develop the model and specification in parallel.

Andrew De Silva, Director, commented: ‘We wanted to upskill the whole architecture team to write specifications on future projects. To do this, we have brought in external specialists to help set up specification templates and work with our team, AECOM. This has ensured that specialist knowledge now exists for both modelling and specifications across the office. We think that our project documentation will work best when all of our designers are understanding and working on the spec in addition to the design.

The process developed by DMA is to plan and identify the different types of systems that will be designed and specified prior to the developed design stage of the project. It was then a case of adding this detail to the model, and adding the same systems to the specification.

Figure 1 below shows an example matrix that outlines the design and specification responsibilities agreed between design team at DMA, the contractor and the client. This planning then ensures that all classifications and type and package codes are clearly understood by the wider team before they proceed.

Figure 1 – Extract from a planning matrix showing system types, responsibilities and notes (Click to enlarge)

The above planning sheet identifies the different types of system. It also clearly identifies the different levels of information needed in each specification. Certain parts of the building will be subject to contractor design portions, so will require performance specifications which are read in conjunction with the Design Intent information. Other parts of the building will require fully prescriptive or proprietary specifications where the Architect is responsible for the Detail Design. NBS Chorus allows for all approaches: from performance specification to inform contractor design, to full proprietary specifications, dropping in product data from hundreds of leading manufacturers.

Simon Lerwill, Director at AECOM Specification Consulting commented: “NBS Chorus has allowed us to combine AECOM’s global expertise with DMA’s digital design methods to deliver a complex project. The platform ensured the information was structured to meet the client’s specific needs and the quality of the output was aligned to the contractual BIM Level 2 requirements.”

In the video below, Andrew shares his thoughts on the benefits of using NBS Chorus within the team and how it enables external collaboration:


With respect to linking the objects in the model together with the specification, two different examples are shown below.

In Figure 2.1, the specification for a hydraulic lift system is associated with the equivalent component object in the model. This allows the specifier to write the specification, whilst better understanding the context of the design. It equally allows the designer to finalize the technical design, understanding the specification.

Figure 2.1 – The linked design and specification developing in parallel (Click to enlarge)

More complex associations were also made. In Figure 2.2 below, seven different wall build-ups are shown. It can be seen that the systems within the walls are associated with the specification. Furthermore, the material layers in the model are also associated with the product clauses in the specification.

Andrew noted: ‘Associating each of the systems and the materials within them with the associated NBS clauses allowed us to easily annotate these on all of the drawings. This has provided the contractor with greater clarity and detail. We can also check that all associations are still valid prior to issuing packages of work’.

This level of linkage provides two major benefits:

  • Efficiency – by linking the items once, the cross references can be added very quickly in all drawings and schedules.
  • Reduced risk – if a classification or type code changes in the model or specification, it can be reported on immediately and corrected. This reduces the risk of the documentation becoming incorrect.
Figure 2.2 – Detailed annotations of systems and material layers (Click to enlarge)

The Architect Sundas Rohilla has been working on the design and specification of the housing project using NBS Chorus. Sundas commented: ‘Linking the specification with the model has helped to make the details more understandable. It has also made the process of checking annotation easier. The consistent use of the Uniclass 2015 codes has meant a clear set of coordinates for documentation’.

In the video below Andrew talks about the benefits of coordinating the model and specification:

To learn more about the subjects covered in this article, follow the links below:

  • NBS Chorus – the cloud specification platform for architects and engineers.
  • DMA and tech led solutions – find out more about DMA and their approach to technology-led solutions.