SRI Calculation Methodology

As defined in the Commission Delegated Regulation 2020/2155, the smart readiness of a building or building unit is determined by the smart-ready services present, planned in, or relevant for the assessed object, and the functionality level of those services.

Learn more about the in-depth SRI calculation.

The SRI support team has produced a technical framework, including a default calculation methodology, practically implemented in the SRI assessment package calculation tool, which can be requested here.

The methodology is structured in three key smart readiness functionalities, as highlighted in point 2 of Annex Ia, to Directive 2010/31/EU, within which there are certain impact criteria.

The SRI assesses nine technical domains.

For each technical domain, smart-ready services shall be defined by Member States, as part of a smart-ready catalogues, including their related functionality levels, and corresponding individual scores for each impact criterion.

The smart-ready catalogues shall reflect the state of art of smart-ready technologies, which may be different among building types. Hence, several smart-ready catalogues may exist. The smart-ready service catalogue shall define the maximum score of each technical domain for each impact criterion.

Member States shall define the respective weighting factors characterising the influence of each technical domain on each impact criterion.

Such factors ought to be expressed as a percentage, the sum of which ought to be 100% for each impact criterion. Weighting factors may be different between building types. As a result, it is possible to obtain the smart readiness score for each impact criterion.

Member States shall define the respective weighting factors of relevant impact criteria within each key functionality, which enables to obtain smart readiness scores along the three key functionalities.

Next, the weighting factor indicate the influence of each key functionality in the total smart readiness score.

Ultimately, the ratio between the smart readiness of the building or building unit compared to the maximum smart readiness that it could reach results in the smart readiness rating. The ratio yields a rating based on the seven-class scale : 90-100%; 80-90%; 65-80%; 50-65%; 35-50%; 20-35%; <20%, ranging from highest to lowest smart readiness.

Step-by-Step Calculation

Once the main functionality level has been defined to each applicable technical domain’s smart-ready service, the calculation proceeds as indicated in Key functionalities, impact criteria and technical domains.

Each smart-ready service $$(S_{i,d})$$ has a certain functionality level $$(FL(S_{i,d}))$$, which is equivalent to a score for each impact criterion (ἰc). The scores $$(I_{ic}(FL(S_{i,d})))$$ of each technical domain(d) and impact criterion are defined by Equation 1, as the sum of the scores of the smart-ready services within a given technical domain.

Equation 1

$$I(d,ic)\;=\;{\textstyle\sum_{i=1}^{Nd}}\;I_{ic}(FL(S_{i,d}))$$

The calculation is reproduced considering the maximum functionality level per applicable smart-ready service contained in the smart-ready service catalogue $$(FL_{max}(S_{i,d}))$$. It is indicated in Equation 2.

Equation 2

$$I_{max}(d,ic)\;=\;{\textstyle\sum_{i=1}^{Nd}}\;I_{ic}(FL_{max}(S_{i,d}))$$

It is possible to produce the smart readiness score per technical domain and impact criterion following Equation 3.

Equation 3

$$SR_{d,ic}\;=\;\frac{I(d,ic)}{I_{max}(d,ic)}\;.\;100$$

Next, the scores per technical domain are summed considering their respective contribution to each impact criterion. The result is divided by the maximum possible score, resulting in the smart readiness score per impact criterion $$(SR_{ic})$$ as per Equation 4.

Equation 4

$$SR_{ic}\;=\;\frac{\sum_{d=1}^N\;W_{d,ic}\;.\;I(d,ic)}{\sum_{d=1}^N\;W_{d,ic}\;.\;I_{max}(d,ic)}\;.\;100$$

Also, the smart readiness per technical domain, following Equation 5.

Equation 5

$$SR_d\;=\;\frac{\sum_{ic=1}^M\;W_{d,ic}\;.\;I(d,ic)}{\sum_{ic=1}^M\;W_{d,ic}\;.\;I_{max}(d,ic)}\;.\;100$$

The smart readiness score per smart readiness functionality(f) is obtained as the weighted addition of the scores per impact criterion as per Equation 6.

Equation 6

$$SR_f\;=\;{\textstyle\sum_{ic=1}^M}\;W_f\;(ic)\;.\;SR_{ic}$$

Finally, the total smart readiness score is obtained as the weighted addition of the scores per smart readiness functionality as in Equation 7.

Equation 7

$$SR\;=\;{\textstyle\sum_{}^{}}\;W_f\;.\;SR_f$$

For the calculation process, the contextual adaptations may have a significant impact.

The total smart readiness score corresponds to a smart readiness rating $$(SR_{class})$$, expressed based on seven smart readiness classes; namely, 90-100%; 80-90%; 65-80%; 50-65%; 35-50%; 20-35%; <20%, ranging from highest to lowest smart readiness.

History of the SRI

Understand how the SRI came into being and learn about the different policy instruments that made it possible.

SRI Framework

Learn about the framework for the common Union scheme used to rate the smart readiness of buildings.