Points calculation in detail

This article explains how to calculate the cost of repairs in euros based on an IPBau assessment.

The three calculation stages

Step 1: Base points
from the IPBau repair code (a, b, c, or d)

Step 2: Weighted points
= Base points × Factor × Size/Quantity

Step 3: Repair costs (€)
= Weighted points × 1.805 × 0.645 × (BKI_D/100) × Difficulty level

The calculation is performed automatically.

Base points (Level 1)

Each IPBau code has a point value:

Important: The exact value depends on the element and its condition.

Weighted points (Level 2)

Formula:

Gewichtete Punkte = Basis-Punkte × Faktor × Größe/Menge (geom. Koeffizient)

Parameters:

1. Factor (default: 1.0) Adjusted if multiple element types or ratings exist for the same element.

2. Size/Quantity (geometric coefficient)
Derived from building assessment figures (e.g., facade area in m², number of apartments)

Example:

58 (Code c) × 1,0 × 850 m² = 49.300 gewichtete Punkte

Renovation needs in € (Level 3)

Formula:

Kosten (€) = Gewichtete Punkte
    × 1,805          [BKI Schweiz 2005 - fest]
    × 0,645          [CHF → EUR - fest]
    × (BKI_D / 100)  [BKI Deutschland - variabel]
    × Schwierigkeitsgrad [variabel]

Fixed parameters (NOT editable):

• 1.805 = BKI Switzerland 2005 (reference value for IPBau method)

• 0.645 = CHF → EUR conversion as of the reference date 2005

Variable parameters:

BKI Germany
Entry: In the diagnosis header under Construction Cost Index (Germany 2005=100) For current values, see https://www.destatis.de

Difficulty Level (Default: 1.0)
Location: In the diagnosis header

• 0.8–0.9 = favorable, mass production, small buildings, good accessibility

• 1.0–1.2 = normal

• 1.3–1.5 = difficult, older buildings, historic preservation, downtown location

Sample calculation

Input data:

• Element: A.03 Facade

• Element type: A.03 Exposed masonry

• Repair code: c - Stains, efflorescence, spalling

• Facade area: 850 m²

• Factor: 1.0 (entire facade)

• BKI Germany: 171 (example)

• Difficulty level: 1.2

Calculation:

Stufe 1: 58 Punkte (Code c)
Stufe 2: 58 × 1,0 × 850 = 49.300 gewichtete Punkte
Stufe 3: 49.300 × 1,805 × 0,645 × 1,71 × 1,2 = 117.777 €

Result: Approx. €117,800 for facade restoration

The Construction Cost Index for Germany

Field

Field: BKI Germany (base 2005)
Format: Integer (e.g., 167)

Conversion

The Federal Statistical Office publishes, for example, Base 2015. For eTASK, you need Base 2005:

BKI (Basis 2005) = BKI (Basis 2015) × 1,097

Example: BKI 152.1 (base 2015) → 152,1 × 1,097 = 166,8 → 167 in eTASK

Source

Federal Statistical Office (destatis.de)
→ Construction and Housing → Construction Price Indices → "Price Index for New Residential Buildings"
Publication: Quarterly, free of charge

Save transparently: System Control - Technical Building Management - Building Diagnosis - Residential Construction Cost Index

Impact (calculation example)

BKI has a proportional effect: +10% BKI = +10% costs

Common errors

1. Size/quantity missing → Cost = €0
Solution: Enter valuation figure in the building

2. BKI Germany = 0 → All costs = €0
Solution: Enter BKI in the diagnosis header (e.g., 167)

3. Factor accidentally set to 0 → Item = €0
Solution: Set factor to 1.0

4. BKI typo → Factor 10 incorrect
Error: 1500 instead of 150 or 15 instead of 150
Solution: Use plausible values as specified by the Federal Statistical Office

Summary

Three levels:

1. IPBau code → Base points

2. × Factor × Size → Weighted points

3. × Conversions → Repair needs (€)

Important:

• Keep BKI Germany up to date

• Check dimensions/quantities in the building

• The condition of the element (repair code) has the greatest influence