Cost planning under DIN 276: cost groups and cost determination

Cost group	Designation	Chargeability under the HOAI
KG 100	Grundstück (site)	not chargeable
KG 200	Vorbereitende Maßnahmen (preparatory works)	conditional
KG 300	Bauwerk Baukonstruktionen (building fabric)	in full
KG 400	Bauwerk Technische Anlagen (building services)	under a threshold rule
KG 500	Außenanlagen und Freiflächen (external works)	conditional
KG 600	Ausstattung und Kunstwerke (furnishings)	conditional
KG 700	Baunebenkosten (ancillary costs)	not chargeable
KG 800	Finanzierung (financing)	not chargeable

From this structure the standard derives two aggregate terms, constantly confused in daily use. Their difference governs every benchmark.

• Bauwerkskosten, building cost, is the sum of cost groups 300 and 400.
• Gesamtkosten, total cost, is the sum of all cost groups from 100 to 800.

The large majority of published cost benchmarks refer to building cost. Reading such a figure as the construction sum understates the budget considerably.

Every cost group is subdivided across three levels: hundreds digits form the first level, tens the second, units the third. The numbering is not continuous, and every group ends with a catch-all position, x90, for other measures.

The catch-all positions deserve attention. They are intended for costs belonging to the group in substance but not attributable to any sub-position. Used as a repository for anything troublesome, they cost the determination its comparability with benchmarks, since comparison proceeds by element group.

The structure in detail is covered in the branch on the cost groups of DIN 276, with articles on KG 300, KG 400, KG 100 and 200 and KG 500 to 800. It also sets out how the three levels are numbered.

Stage	Basis	Depth of treatment	Work phase
Kostenrahmen (cost framework)	briefing	first level	1
Kostenschätzung (cost estimate)	concept design	second level	2
Kostenberechnung (cost calculation)	developed design	third level	3
Kostenvoranschlag (pre-tender estimate)	construction preparation	third level and packages	6
Kostenanschlag (tender sum)	procurement and construction	by procurement package	7
Kostenfeststellung (final cost statement)	verified invoices	third level	8

Four of these stages are carried out once at a defined point in the project. The pre-tender estimate may be repeated and carried out in several steps, and the tender sum is prepared several times during the project.

The Kostenvoranschlag was newly introduced with the 2018 edition. It corresponds to the former Kostenanschlag but now precedes it. A considerable share of the available material predates that change and still lists five stages, with the terminology simultaneously shifted.

The stages in detail are covered in the branch on the stages of cost determination. It also sets out which stage was added in 2018.

The standard defines cost planning as the totality of measures for cost determination, cost control and cost management. Determination alone therefore does not satisfy the standard.

Component	What it achieves
Kostenermittlung	forecasting or establishing costs
Kostenkontrolle	comparing the current determination against its predecessors
Kostensteuerung	targeted intervention in the development of costs

The great majority of treatments of this subject cover only the first component. The other two, however, decide whether a project succeeds, since a determination describes a state while management changes it.

For cost management a principle applies that is rarely stated: costs are only ever a reflection of the design in hand. Changing the costs requires changing the design. Lowering allowances without a design change is not management but a deferral of the problem.

Both are covered in the branch on cost control and cost management. It also sets out what cost management is not.

Anrechenbare Kosten, chargeable costs, are the basis on which fees are calculated. They derive from the cost determination but are not identical with construction costs.

The logic of chargeability is consistent: what is chargeable is what the designer designs. They do not design the site, nor their own fees, and financing lies outside their remit.

A special rule with a threshold applies to technical installations: up to an amount equal to 25 per cent of the other chargeable costs they are chargeable in full, and the portion above that at half. Above that threshold they enter at half.

That threshold is why the boundary between building fabric and technical installations is the most fee-relevant allocation question in the whole standard. Moving an item from one group to the other lowers the threshold and increases the portion chargeable only at half. The fee basis comes out lower without anything having changed in the construction cost.

Two further points belong here. Value added tax is expressly not part of chargeable costs. And in existing buildings, the fabric being incorporated must be appropriately taken into account, which raises the fee basis directly and simultaneously shifts the threshold of the special rule upwards.

The branch on chargeable costs covers this system in detail. It also sets out which cost groups do not enter at all.

This is the central insight of the field and the source of most errors arising in practice. Cost planning in German construction rests on several bodies of rules updated at different times and therefore out of step.

Constellation	Where the divergence lies
DIN 276 of 2018 against DIN 276 of 2008	The 2018 edition governs cost planning; for chargeable costs the HOAI still points to the 2008 edition.
DIN 276 against the HOAI on stages	The standard has six stages; the HOAI carries three as basic services. The pre-tender estimate has no counterpart in the HOAI.
DIN 276 against the HOAI on depth	The standard requires the third level for the cost calculation; the HOAI at least the second.
DIN 276 against guidelines on model-based determination	Completion levels are referenced to levels of the cost structure whose requirements the standard has since deepened.

None of these divergences is an error in any of the rules. They follow from the fact that a standard can be updated faster than an ordinance.

A rule follows for practice that carries this whole field: before any cost determination, establish which body of rules in which edition governs for which purpose, and put that determination in the contract. Disputes about the governing edition almost always arise later, at final account stage, and almost always because nothing was agreed beforehand.

The coexistence of editions is covered in the version problem, and the allocation of stages in basic services versus additional services. It also sets out how a reconciliation between the two is built.

Five changes act directly on daily work.

Cost group 800 Financing is new. Financing costs were removed from cost group 700. Anyone calculating on older rules of thumb drops them without noticing.

The pre-tender estimate is a new stage. It closes the gap between design and procurement, that is the period in which most detailed decisions are taken.

The required depth was deepened. The cost estimate now requires the second level rather than the first, the cost calculation the third rather than the second.

Building and civil engineering share a uniform structure within cost groups 300 and 400.

Cost group 500 was extended and now also covers open spaces independent of any building.

A quieter change is nonetheless felt: the former cost groups for architect and engineer services and for surveys and consultancy were dissolved and redistributed into lead design and specialist design. The ordering now follows the kind of design rather than the profession.

Almost every treatment of this subject quotes accuracy figures by stage, usually plus or minus 30 per cent for the cost estimate, 20 for the cost calculation and 10 for the tender sum. They are routinely attributed to DIN 276.

The standard does not contain these values. It describes the stages by purpose, basis and degree of detail but prescribes no permissible deviation. The circulating percentages are values drawn from professional literature.

They remain usable for communicating uncertainty to a client. As justification for a deviation they do not serve, since a different measure applies: legally the question falls to be decided in liability for an incorrect cost determination, and there the first distinction is whether a cost ceiling was agreed.

Without an agreed ceiling, the designer owes a determination free of defects and is granted a tolerance band. With an agreed ceiling there is an agreement as to a characteristic of the work, and exceeding it constitutes a defect in the design service. Whether a tolerance then still applies is not answered uniformly in the case law.

How easily a ceiling arises unnoticed deserves particular attention: communication of the client's cost expectations can suffice where the designer does not expressly contradict them. The article on cost risks, contingencies and tolerances covers this position.

Cost control presupposes that two determinations are comparable. Four attributes must stay constant across the stages for that: the structure, the scope, the tax presentation and the reference quantities.

If one breaks, the difference between two totals is not a cost deviation but a presentational effect. This is no methodological nicety: case law has already established that schedules ordered by trade and updates ordered by cost group yield no comparability beyond the total.

The practical conflict arises from the pre-tender estimate onwards, because ordering by procurement package is added there and trades do not coincide with element groups. The solution is to retain the cost group structure as leading and carry procurement packages in parallel rather than switching. The article on trade-oriented cost structure covers that variant.

DIN 276 captures the costs of the construction project, that is the investment. Costs arising after handover are the subject of a separate standard for costs in use.

The separation is substantively right but creates a gap precisely where the most important decisions are taken. Numerous early design decisions shift costs between investment and operation: insulation thickness, plant strategy, material choice, service life of elements. Anyone applying only DIN 276 assesses such decisions one-sidedly.

How the three relevant standards relate to one another is covered in DIN 276, DIN 277 and DIN 18960 compared. It also sets out why costs in use are not costs within DIN 276.

On projects in existing buildings the weight of the components shifts without the system changing. Four points differ from new build.

The starting condition is less certain than the target. In new build the object is fully definable; in existing buildings part of the scope demonstrably cannot be known before the fabric is opened up. The contingency is therefore not caution but professionally required, and it is to be stated rather than absorbed.

Strip-out follows the element. Partial demolition, repair, temporary support and dismantling are allocated to the cost group whose element they affect. They therefore spread across the whole of cost group 300 rather than forming a block of their own.

Existing fabric belongs to the fee basis. It generates design effort but no construction cost, and without applying it, greater effort meets a smaller fee basis.

Trade-oriented structuring is frequently closer to the substance. The standard names modernisation expressly as a case for it, because in existing buildings whole elements are not created; individual measures are carried out on existing ones.

Cost planning is frequently described as the lead designer's task, which is only partly right. Determination, assessment and decision must be kept apart.

Role	Contribution
Lead designer	prepare the determination, identify deviations, develop measures
Specialist designers	determine the cost of services and structure, set out alternatives
Client	decide on accommodation, quality, standard and programme
Project manager	coordinate the process, obtain and record decisions

The third row is decisive. Every effective management measure touches characteristics of the building on which the client alone decides. The designer supplies decision papers, not decisions.

From the second row follows a recurring conflict: the cost calculation is to be prepared in work phase 3, while specialist design is in practice frequently commissioned only after work phase 4. A substantial part of the figures therefore comes from design work that does not yet exist at that point, and cost group 400 in particular then comes out too low.

Eight errors recur across this field and can be drawn together from its articles. All of them concern either the allocation or the reference quantity.

Not fixing the edition. Different editions govern cost planning and chargeable costs. Without a contractual determination, the dispute surfaces at final account stage.

Working with five stages. The pre-tender estimate is then missing, and with it the determination at the interface between design and procurement.

Falling short of the required depth. A cost estimate showing eight totals no longer satisfies the current edition.

Citing tolerances as a requirement of the standard. It contains none. The question falls to be decided in liability, and there first on whether a ceiling was agreed.

Changing the ordering between stages. Cost control then ends, and chargeable costs can no longer be derived directly.

Building estimates into the tender sum. It may contain only tenders, orders and costs incurred. Otherwise the share of budget actually committed stays unknown.

Passing over the existing fabric. In existing buildings it forms part of the fee basis and is routinely not applied at contract stage.

Agreeing a cost ceiling unnoticed. Unrealistic cost expectations must be contradicted expressly and on the record.

1. Fix the governing editions, separately for cost planning and for chargeable costs, and name both in the contract.
2. Name the cost determinations owed, including those that are not basic services, stating the depth of treatment.
3. Test the feasibility of the cost target before fixing it, and state the cost groups it covers.
4. Fix a leading ordering and retain it across every stage, with additional criteria carried in parallel.
5. Show quantities and unit rates separately, so that deviations remain attributable.
6. State contingencies rather than absorbing them, with a reason and a release event.
7. Compare continuously and attribute by cause, not only at changes of stage.
8. Analyse the final cost statement, so that the project yields in-house benchmarks for future work.

The first point costs ten minutes and prevents the commonest dispute in this field. The eighth costs a day and is the only source of sound benchmarks of your own.

The cost structure

• The cost groups of DIN 276 at a glance
• KG 300 building fabric: structure and allocation
• KG 400 building services: structure and allocation
• KG 100 and KG 200: site and preparatory works
• KG 500 to KG 800: external works, furnishings, ancillary costs, financing

The stages of cost determination

• The six stages of cost determination under DIN 276
• Cost framework and cost estimate: the early stages
• Cost calculation at the third level of the cost structure
• Pre-tender estimate and tender sum distinguished
• The final cost statement and analysis for future projects
• From cost estimate to cost calculation: the transition

Cost control and cost management

• Cost control and cost management through the project
• Target-actual comparison of cost determinations
• Cost management: intervening rather than recalculating
• Cost risks, contingencies and tolerances

DIN 276 and the HOAI

• Chargeable costs under DIN 276 and the HOAI
• The version problem: DIN 276 of 2008 and of 2018
• Existing fabric in chargeable costs
• Which cost determinations are basic services and which are not

Applying it in practice

• Applying the cost structure in practice
• Trade-oriented cost structure by procurement package
• BIM-based cost determination by cost group
• DIN 276, DIN 277 and DIN 18960 compared