VOB/B § 2 Abs. 3 Nr. 3 · § 8 Abs. 1

Recover Your Overhead Costs — automatically calculated

Construction companies leave millions on the table — because overhead cost recovery seems too complex. GKA Tool handles it in minutes. No expert. No license. No risk.

Calculate for Free → How It Works Ask a Question or Request Representation →

Free preview of your claim — pay only after the calculation

After payment: PDF + invoice automatically sent to your billing address

Document ready to submit to the client — no further effort

Sample Calculation

PositionGK-Adjustment

§ 2 Para. 3 — Under-coverage- 74.920 €

§ 2 Para. 3 — Over-coverage+ 33.785 €

§ 8 Para. 1 — Zero Quantities- 54.897 €

Neutral (±10%) — 3 Pos.—

RECOVERY CLAIM

96.033 € net

VERIFIABLE
PER VOB/B

How It Works

Get Your Document in 4 Steps

No expert, no installation, no prior knowledge required.

Download Templates

Download our Excel templates — one for EFB-221 data, one for your bill-of-quantities positions.

Enter Data

Enter BGK/AGK/W+G overhead rates and all positions with planned and actual quantities.

Upload & Review

System calculates under/over-coverage — result visible immediately, free of charge.

Submit Directly

After payment: complete, verifiable document instantly — ready to submit directly to the client. No further effort.

Concrete Example

What This Means in Practice

A public infrastructure project (civil engineering) with 38 positions. Contract sum 3.75M €, final account 2.95M €.

Of 38 positions, 24 positions deviate by more than ±10% from planned quantities. Without GKA, the company bears the overhead deficit.

GKA Tool automatically detects every deviation, classifies it correctly per VOB/B and calculates the recovery claim in seconds.

Cost for this document: 1,920.67 € (2% of 96,033 €)
ROI: 1:50 — the investment pays off on the very first use.

Contract Sum

3.754.671 €

net

Final Account

2.946.976 €

- 807.695 €

Under-coverage § 2 Para. 3

- 74.920 €

Over-coverage § 2 Para. 3

+ 33.785 €

Zero Quantities § 8 Para. 1

- 54.897 €

Recovery Claim
96.033 €
net

Legal Basis

Why You Are Legally
Entitled to This Money

The law protects you — but only if you apply it.

VOB/B § 2 Abs. 3 Nr. 3

Price Adjustment for Quantity Deviations

If actual quantities fall more than 10% below planned, you are entitled to an increase in the unit price. This adjustment must be actively asserted.

"... the unit price for the actually executed quantity shall be increased upon request, insofar as the contractor does not receive compensation through increased quantities in other positions."

VOB/B § 8 Para. 1 (Zero Quantities)

Compensation for Unexecuted Works

Positions with zero execution quantity are treated as partially terminated works. According to Korbion/Ingenstau (17th ed., para. 34/35), the contractor is entitled to compensation — without written termination.

"A written termination is not required here — positions with zero execution quantity are to be compensated as terminated works." — Korbion/Ingenstau VOB Commentary

BGH Ruling 30.10.1997 · VII ZR 222/96

Performance-Related Risk is Deducted

The BGH ruled that performance-related risk cannot be reimbursed for unexecuted works. GKA Tool implements this automatically — correctly and verifiably.

The claim is correctly reduced by the performance-related risk, as established by the BGH — ensuring acceptance by the client.

Literature & Methodology

Recognized Construction Management Principles

The calculation is based on industry-standard references and meets the methodology accepted by experts and courts.

Korbion/Ingenstau 17th ed. § 2 Para. 3 No. 7ff. · Kapellmann/Schiffers 5th ed. Ch. 7 · EFB-Preis 221 Procurement Handbook

Your Benefits

What Makes GKA Tool Different

Legacy desktop software versus a modern online tool — the difference is fundamental.

💰

Recover What You Are Owed

When quantities deviate by more than ±10%, a claim arises — which lapses without active assertion. GKA Tool makes it so simple that no claim goes unnoticed.

⚡

Minutes Instead of Weeks

What used to take experts weeks and 5,000–20,000 € you now handle yourself — in under an hour, for a fraction of the cost.

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Verifiable Document

The generated PDF meets professional construction management standards — with complete Annex 1, legal basis, literature references and signature block.

🔓

No Upfront Investment

No purchase, no license, no monthly fee. You pay 2% of the claim — and see the result for free before you even decide.

🌐

Online — Instant & Everywhere

No download, no installation. Open browser, upload files, done. Works on the laptop on the construction site just as well as in the office.

🤝

Personal Representation & Support

We personally represent your claim to the client — from document preparation to negotiation. Request an individual quote for full support.

Comparison

GKA Tool vs. Traditional Alternatives

Criterion

GKA Tool

Desktop-Software

Expert

Instantly available, no installation

✓

✗

Transparent pricing publicly visible

✓

✗

Pay-per-use — no fixed costs

✓

✗

✓

Result preview before payment

✓

✗

Print-ready legal PDF

✓

Excel/Word

✓

Automatic B2B invoice

✓

✗

Manual

Typical costs per project

300–2.000 €

License required

5.000–20.000 €

Testimonials

What Our Clients Say

★★★★★

„Wir hatten noch nie eine GKA gestellt, weil uns der Aufwand zu hoch war. Mit GKA Tool war es in zwei Stunden erledigt — und der Auftraggeber hat die Forderung anerkannt."

M. R.

Bauleiter · Tiefbau · Bayern

★★★★★

„Das Dokument hat auf Anhieb überzeugt — vollständige Anlage 1, alle Rechtsgrundlagen, klar strukturiert. Der AG hat ohne Rückfragen gezahlt."

S. K.

Geschäftsführerin · Rohrleitungsbau · NRW

★★★★★

„Ich war skeptisch ob ein Online-Tool ausreicht. Das Ergebnis war professioneller als manches was ich von Sachverständigen gesehen habe. Klare Empfehlung."

T. H.

Projektleiter · Hochbau · Baden-Württemberg

Pricing

Simple. Transparent. Fair.

You only pay if you have a claim — and see it for free before you decide.

PAY PER USE

^from300 €

2% of the recovery claim · minimum 300 € · excl. VAT

✓
Complete GKA calculation per VOB/B § 2 Para. 3 + § 8 Para. 1
✓
Print-ready, verifiable PDF document (10+ pages) incl. Annex 1 — ready to submit to the client
✓
All legal bases and literature references
✓
Automatic B2B invoice after payment — sent directly to your billing address (incl. VAT No.) for correct accounting
✓
Instant delivery by email + download
✓
Free claim preview before payment
+
Optional: Personal representation & full support with the client — Request quote

Calculate for Free →

No upfront payment · No license · No hidden costs · Secure checkout via Stripe

🧾Invoice automatically after payment: You receive the invoice at your billing address — incl. VAT No. for correct tax accounting as a business expense. No manual effort.

FAQ

Frequently Asked Questions about VOB/B and GKA Tool

About GKA Tool

About Us

GKA Tool was developed by construction management experts and software engineers with years of practical experience in claims management.

📐

Construction Management Expertise

The calculation logic was developed by experienced construction management specialists and corresponds to recognized technical literature.

🔒

Data Security

Your files are transmitted encrypted and automatically deleted after 24 hours. Payments run exclusively via Stripe.

📬

Personal Support

For questions about the input or the document, we are available by e-mail — and if needed also for personal consulting.

The Problem We Solve

„Construction companies don't assert GKA claims — not because they have no entitlement, but because the calculation seems too complex."

The reality: Every project with quantity deviations over ±10% has claim potential. With a contract of 2M € and a typical GK coefficient of 14%, the under-coverage can quickly reach five to six figures — money the company is legally owed.

GKA Tool makes the calculation so simple that no claim goes unnoticed.

Personal Support

Need Individual Support?

Whether questions about the calculation or full personal representation with the client — we stand by your side from document to successful enforcement of your claim.

📝

Contact Form

Describe your request — we will get back to you within 24 hours.

🎤

Full Representation with the Client

We prepare the documents, personally present the GKA and represent your claim until settlement — individual quote on request.

📊

Calculation Consulting

Unsure about the input data? We help you determine the correct values.

Your Request

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Recover Your Overhead Costs — automatically calculated

Get Your Document in 4 Steps

What This Means in Practice

Why You Are LegallyEntitled to This Money

What Makes GKA Tool Different

GKA Tool vs. Traditional Alternatives

What Our Clients Say

Simple. Transparent. Fair.

Frequently Asked Questions about VOB/B and GKA Tool

About Us

Need Individual Support?

Calculate Your Claim Now

Why You Are Legally
Entitled to This Money