Specifications

Bill of Quantities - A bill of quantities (BoQ) is a detailed, itemized description of all construction work to be performed for a construction project or renovation. It serves as the basis for soliciting bids, the construction contract, and subsequent billing. The BoQ is typically prepared by the architect or specialist planner and follows the structure of the VOB/C (General Technical Contract Conditions for Construction Work).

Organization and Structure

A bill of quantities is organized by trade (e.g., structural work, carpentry, plumbing, electrical, painting) and contains the following for each item: a unique item number, a precise description of work, the quantity (e.g., m², m³, pieces, lump sum), the unit price (to be filled in by the bidder), and the total price. The sum of all items results in the total bid amount.

Well-formulated service descriptions are neutral and describe the desired service without prescribing specific products or manufacturers. If a specific product must be named (for example, due to technical compatibility), the phrase “or equivalent” is commonly used. Contingency items-services whose execution depends on decisions made during the construction phase-are included as optional additions with the notation “contingency item,” without being factored into the total bid amount.

Significance for Construction Practice

The bill of quantities is the central control instrument of a construction project. It ensures comparability (all bidders calculate the same services), cost transparency (each item is priced individually), contractual certainty (the bill of quantities becomes part of the construction contract), and clarity in billing (quantities actually delivered are billed item by item). An incomplete or unclear bill of quantities is the most common cause of construction cost supplements and disputes.

Bill of Quantities Software and Digital Processing

In modern construction practice, bills of quantities are created using AVA software (tendering, awarding, billing): Common systems include ORCA AVA, G&W; AVA, RIB iTWO, or Arriba. These programs enable automatic quantity takeoffs from CAD drawings, price comparison between bidders, and digital management of change orders. Standard specifications from the STLB-Bau (Standard Construction Specifications) provide ready-made text modules that the planner adapts to the specific project. The use of STLB texts significantly improves the quality and completeness of the scope of work and reduces the risk of incomplete items.

Practical Tip for Building Owners in Nuremberg

We recommend that building owners in the Nuremberg metropolitan region have the scope of work prepared not by the contractor, but by an independent architect or specialist planner. This is the only way to ensure a neutral scope of work. Have the scope of work reviewed by a building expert before the bid invitation-gaps and inaccuracies are still easy to spot at this stage and can be corrected at no cost. Addenda during the construction phase, on the other hand, are almost always more expensive than careful advance planning.

In the Nuremberg region, the market for tradespeople is currently tight, and businesses are operating at full capacity. This means that poorly drafted specifications lead to higher risk premiums in bids-tradespeople factor in the ambiguities. A precise specification signals professionalism to the bidder and generally results in more competitive, realistic bids. We are happy to connect you with experienced architecture and planning firms in Nuremberg and Erlangen that prepare specifications for private renovations and new construction.

Frequently Asked Questions

How much does it cost to prepare a bill of quantities?

Preparation is part of the architect’s services and is remunerated according to the HOAI (Fee Schedule for Architects and Engineers) as part of Service Phase 6 (Preparation for Award). For a construction project with construction costs of 400,000 euros, the architect’s fee for Service Phase 6 is approximately 5,000-10,000 euros-an investment that quickly pays for itself through savings on change orders. For smaller renovations (bathrooms, roofs), specialized experts and construction supervisors often offer flat-rate packages for preparing specifications.

Can I, as a layperson, review a bill of quantities?

In principle, yes, but the technical terms and references to standards make it difficult. Pay attention to: a complete listing of all trades, plausible quantity specifications, clear service descriptions without gaps, and an item for contingencies (contingency items). Check whether waste disposal, site setup, and cleaning are included-these items are often overlooked and then appear as costly change orders. If in doubt, we recommend having a construction expert review the specifications.

What happens if there are discrepancies between the scope of work and the actual work performed?

If the quantities actually delivered differ from those in the scope of work (either more or fewer), billing is based on unit prices. Additional services not included in the scope of work are considered additional work and must be agreed upon and paid for separately. Without a written addendum agreement, the contractor is not entitled to additional compensation. Important: In the case of lump-sum contracts, the agreed lump sum applies, provided that the scope of work has not changed.

How does a unit price contract differ from a lump-sum contract?

In a unit-price contract, all items in the scope of work are listed with quantities and unit prices; billing is based on the quantities actually delivered. In a lump-sum contract, a fixed total amount is agreed upon-the contractor bears the quantity risk. For private builders, the lump-sum contract offers greater cost planning security but requires a well-drafted scope of work as a foundation.

Which items are most frequently omitted from the scope of work?

In practice, certain services repeatedly appear as costly change orders because they were not included in the original scope of work: site setup and cleanup, water and electricity for the construction site, disposal of demolition debris and packaging, cleaning after completion of work, and restoration of surfaces after pipe penetrations. Especially in renovation projects in Nuremberg’s older buildings, unforeseen demolition work (e.g., exposing plastered wooden beam ceilings, removing old lead pipes) often arises, which is billed as a change order if not explicitly listed in the specifications. Those who agree on such risk items in advance as “on-demand” items with a unit price in the specifications avoid cost surprises: The contractor has no incentive to inflate the item’s cost if the unit price has already been agreed upon.

Specifications and Proof of Funding

For energy-efficient renovations funded by KfW or BAFA, the specifications play an additional role: As the basis for awarding the contract, it must contain binding technical minimum requirements (e.g., U-values for windows, insulation thicknesses, COP values for heat pumps). A specification that is too vague-such as “Windows according to DIN, quality at the contractor’s discretion”-is not sufficient for subsidy verification; the energy consultant must demonstrate in the proof of use that the subsidized measures meet the requirements. A technically precise scope of work that already takes the BEG program’s subsidy conditions into account during the bidding phase saves on subsequent documentation and significantly speeds up the processing of subsidies. We recommend that building owners in Nuremberg and Franconia involve energy consultants early in the preparation of the specifications-the BAFA publishes a database of experts with certified energy consultants who can demonstrate relevant experience.

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