Workshop Materials & Circulair Construction REAP+ TU Delft

Circular City ( deepens their insights in Circular Buildings by support of BRIQS Foundation as expressed on her website. Also from the EU Horizon 2020 innovation program will be further research done, now primarily focused on building circular, not buildings. As this research Buildings as Material Banks of BAMB is led by Brussels Environment, it will be further developed the coming period.

Workshops initiated by BRIQS Foundation at the TU Delft in collaboration with – among others – five universities and colleges to come to measure circularity of buildings. Various researchers, teachers, doctoral students, graduates and participants from the industry are participating along.

Following is a reflection of the four workshop sessions. It is always given a brief introduction, followed by concluding the key learning points. This can be seen as an inventory of the complexity of the issue as well as a definition of the relevant aspects and the careful formulation of principles.

The research report Circular Materialen & Product flows in Buildings was presented on July 1, 2015 on the C2C Inspired lab TU Delft Congress. It can be downloaded via the above link and is also available in Dutch.

A force, but also potential danger of the workshops was the diversity of the guests, whose varied composition per session. This discussion was both deep and wide plugged and some topics were discussed several times. Repeating some of the aspects mentioned above are the logical consequence, already underlining this being their special relevance.

Workshop 1: Introduction and actors

The first workshop was intended to get a better grip on the concept of “circular building,” the role of raw materials, materials and products therein, and current and future players in the field. Important questions are: Who are the stakeholders? What are the obstacles? What are at the end of the day the key themes?

Presentation by Bob Geldermans TU Delft with link; MaDCiB 1 BGeldermans. Further presentation fragment by Remko Zuidema from the February 3rd presentation at TU Delft from Slideshare.

Lessons learned

  • The main addition of the circular thoughts to the principles of Open Building is the condition that the removable instalment consists of components and materials that can be reused or recycled in quality.
  • If the various floors (base building / fit-out) would be separated, this means a division in two (or more?) in the world of contractors. It then opens a separate junction potential market. Importantly there is the potential shift of Business-to-Business (B2B) to Business to Costumer (B2C) for construction which is a great opportunity for different communications especially for the fit-out towards the consumer;
  • Ownership plays an important role in the feasibility of circular models. Distinction between legal and beneficial ownership is important. This is in Dutch law enshrined in the Civil Code and always asks separate notarial and land registry record in the formation of legal ownership in contrast to neighboring countries;
  • In a model that distinguishes between different floors, each with its own velocity, the interface of these layers is crucial. One has to deal with different suppliers. For example Who provides the coupling of the pipes to the plant?

Workshop 2: Theme FLEX 2.0 and adaptive capacity building

The second workshop was entirely devoted to the study of Rob Geraedts (TU Delft Real Estate & Housing) to “adaptive capacity building” [2015]. He gave a lecture in which the future value of buildings is explained on the basis of financial efficiency, durability and adaptability. On the latter, he goes on further. This involves offsetting changes from society, the owner or user. The adaptive capability of a building should facilitate that change, instead of trying to avoid her. Years of research have resulted in – it still is developing – document FLEX 2.0.

Presentation of Rob Geraedts MaDCiB 2 RGeraedts on the product FLEX 2.04 RG NL 090315 Notatieformulier and FLEX 2.04 RG NL 090315 Volledig as temporary research results.

Lessons learned

  • A building must be adaptable in order to continue to meet the needs of both user and investor. This flexibility should not be a goal in itself but a means to save money and / or to generate quality / money;
  • Flex 2.0 includes Rob Geraeds build interesting indicators on adaptive and the role of materials in it. The values ​​attached to it, further research is important;
  • There are three identified key themes that form the overlap between adaptive and build circular: oversizing, connections and dimensions;
  • Designing buildings in a way that the materials retain their quality (circular) is particularly relevant as we face a future where material scarcity will have economic consequences;
  • Communication is an essential bottleneck. Buildings can then be adaptable, be removable or expandable, but if the user does decide upon or even not know about it, it is in vain.

Workshop 3: Theme Building materials and their properties

In the 3rd workshop session, the focus was on raw materials, materials and products. There is discussed what kind of materials / products are traditionally used in construction and how it will change in the run-up to circular buildings. The focus of the discussion was in defining characteristics and conditions that foster circularity. What is the reuse potential of a material or product? How can they release the highest possible quality of buildings? The center of gravity is shifting from material to automatically connect. How various building elements and products are connected to each other, and whether this compound is reversible.

Dimensioning and standardization play in this discussion an important role when it comes to universality and interchangeability. Presentation by Bas Slager of Repurpose. And presentation of Jouke Post of XX Architects, not provided for public.

Lessons learned

  • Standardizing on material level creates conditions for recycling. Standardization at product level creates conditions for connections and connectors;
  • Entering standardization imposes restrictions on the freedom of design and will have a reduction in the diversity of our built environment result;
  • Digital production can regulate specific questions on a material efficient manner where standardization of products is not always the best solution;
  • Standardization of measurements; is not needed if the connections between elements are standardized;
  • If the difference in value between the product and material / raw material is large, it makes sense to apply standardization;
  • Lifetime Determination of each building layer should be defined at the beginning of the design process so that material and product selection can be tailored accordingly.

Workshop 4: Theme Economic models and build circular

During the 4th and final session, the focus was on exploring economic opportunities and pitfalls in the transition from a linear to a circular economy. The main topics discussed here are:

business, procurement, regulatory, digitization and private and public value.

Presentation of Rene de Klerk of Rendemint and presentation of Ruben Vrijhoef of Hogeschool Utrecht MaDCiB 4 RVrijhoef.

Lessons learned

  • Data input of building materials has advantages in all stages of life.
    – During the use phase the producer or supplier of a certain product can be traced back in the event that something needs to be replaced, repaired or dismantled;
    – Prior to the demolition phase, a demolition contractor knows exactly what is in the building material and in time start looking for the right buyers / processors of these materials or products;
  • It penetrates circularly ideas in two ways: Bottom-up (step by step to change the current practice) or top-down (for example, change imposition via legislation);
  • The distinction between ‘less bad’ and ‘good’ (as made in the C2C philosophy) also applies to the construction: Downcycling from existing buildings is ‘less bad’, designing buildings from completely circular Principles ‘good’;
  • Circular cycles with most of the existing output not feasible. A better use of demolition of existing stock which constitutes a significant step forward, especially if this can be applied locally and if there was an order of assessment in advance: Demolition necessary? Share reusable directly? Etc. The question is whether this is the right step towards a circular building paradigm, because it can also perpetuate traditional patterns;
  • The transition to circular earning is mainly decided in future legislation concerning the following aspects:
    – Quality and properties of materials (eg .: toxicity, purity, etc.);
    – Procurement Methods / tenders / contracts with suppliers;
  • Recycling processes will have to improve technically if we want to recycle materials 100% without having to add pure raw materials to it.


From literature and the workshop sessions there it is possible to draw valuable lessons in support of the step towards practical implementation of circularity in the construction industry. Those findings come together and work towards a set of key indicators and a roadmap.

  1. Firstly, building materials and products meet a number of criteria which the intrinsic properties are in order;
  2. Furthermore, the products must be made in consultation with the design and use of the building, which we relational properties;

At the intersection of the two we will find paired indicators of circular building, from a predominantly technical perspective, manifesting. These indicators are:

  • The exact composition of the material or product;
  • The performance quality of the material or product;
  • The intended (re) uses path of the material or product;
  • The possible duration of performance material, product, component or service;
  • The applied connection technology between materials, products or components;
  • The applied dimensions of the materials, products or components;
  • The data quality of the recording.

Despite the technical accent we find obviously multiple other adjacent domains in this study: How is it financial and logistically secured, for example? Such assurance is surrounded by legal, economic and regulatory factors. A complex interplay with technical, social, financial, legal and organizational aspects can be hard to separate from each other …

This post is also available in: Nederlands