Introduction

In this step we will calculate the diviersified flow and the diversity factor.

The diversity flow is the maximum sum of all domestic hot water flows within the building, taking into account that not all tapping points are used at the same time.

The diversity factor is defined by the division of the diviersified flow through the theoretical total domestic hot water flow, and results in a number between 0% and 100%, indicating the maximum “probability“ or “statistic chance“ of having parallel tappings.

The theoretical total domestic hot water flow is the sum of all individual tap design hot water flows.

Calculation method & order of calculations

The first thing a user must select is the “calculation method“ to calculate the diversity flow and diversity factor. This selection is important because it will influence the order in which we calculate both.

static

If static is selected, the user must enter the diversity flow directly. In that case we will “reverse engineer“ the diversity factor based on the standard as explained below.

diversity standard

If diversity standard is selected, the user must enter the diviersified flow directly. In that case we will “reverse engineer“ the diversity factor as explained below.

“Number of dwelling” based diversity standards

Some diversity standards are only dependent on the number of dwellings, like :

In this step we calculate for one single dwelling, so the diversity factor can be defined by the formula with the number of dwellings (N) equal to one.

diversity factor

For most standards based on number of dwellings, the diversity factor within one dwelling is 100%.

diversity flow

“Flow based“ based diversity standards

Option 1 : the user defines the tapping points

diversity flow

If the tapping points are defined, we can calculte the theoretical total DHW flow as a sum of all individual tapping points. We then use the diversity formula to calculate the diversity flow. An example can be found at Based on DIN 1988-300

When calculating the diversity flow, we sum up the individual flows without recalculating them (as explained in Step 1 : recalculation of the tapflows). In other words : we calculate the diversity factor for a “standardised“ situation.

Why? because diversity formula’s are inted to express a “probability“, a “statistic chance“ of having parallel tappings. These probabilities are independent of temperature regimes. We call this probability the diversity factor as explained further on.