The progress certification is one of the most important documents in construction. It is the legal mechanism through which completed work is validated, the developer or client is invoiced, and the right to payment is established. In Spain, the process is regulated by law and has specific features you need to understand.
What is a progress certification?
A progress certification is an official document that attests that a certain quantity of work has been executed on a construction project during a specific period (typically one month).
Main functions of a certification:
- Legal validation: It certifies to the developer, creditors, and tax authorities that the work has been completed in accordance with specifications.
- Basis for invoicing: It is the legal foundation for issuing an invoice to the developer and establishing the right to payment.
- Progress control: It allows the developer, the client, and the public administration to supervise the progress of the project.
- Income protection: The issued and accepted certificate is proof that you have completed the work and are entitled to payment, even if disputes arise later.
- Basis for final settlement: When the project ends, the accumulated certifications define the final result.
Legal framework in Spain: LOE and FIDIC contracts
Ley de Ordenación de la Edificación (LOE) (Building Regulations Act)
The LOE (Ley 38/1999, Building Regulations Act) is the fundamental law governing building construction in Spain. It establishes:
Article 9: The contractor must guarantee the execution of the works in accordance with the project, budget, conditions of contract, and technical specifications. Certifications are the validation mechanism.
Article 13: Defines the role of the supervising quantity surveyor, who is responsible for validating certifications before payment is made.
Payment deadline: The client (developer) is obligated to pay within a maximum of 30 days from the submission of the certification (although many contracts negotiate 45–60 days).
FIDIC contract
Although more common in civil engineering works, many Spanish construction companies use the general conditions of FIDIC (Fédération Internationale des Ingénieurs-Conseils) contracts, which include detailed certification procedures:
- Certification submission: The contractor submits an "Application for Payment" with measurements, costs, and supporting documentation.
- Inspection: The Engineer (supervisor) inspects and validates the measurements.
- Issuance: The Engineer issues the "Certificate of Payment" validating the amount.
- Retentions: Guarantee retentions are applied in accordance with the contract (typically 10%).
Subcontracting Act in Construction
Ley 32/2006 de Subcontratación en la Construcción (Act 32/2006 on Subcontracting in Construction) establishes that:
- The contractor must pay subcontractors within a maximum of 15 days from the developer's certification.
- Certifications issued to subcontractors must be for the same amount certified to the developer (no unjustified additional retentions).
- Failure to pay subcontractors on time is subject to sanctions.
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Types of certifications
Monthly certification
The most common. Issued each month (or every two weeks on fast-moving projects) for the work completed during that period.
Contents:
- Validity period (e.g., "April 1 to April 30, 2026")
- Work items completed with quantities (m², kg, units)
- Unit prices per line item
- Total certification amount
- Applicable retentions
- Net amount to be collected
Example:
- Line item "Concrete structure": 50 m³ × €200/m³ = €10,000
- Line item "Floor slab": 200 m² × €40/m² = €8,000
- Total certification: €18,000
- 10% retention: €1,800
- Net to collect: €16,200
Partial progress certification
Issued when a milestone or project phase has been completed, even if it is intermediate (e.g., "Structural phase complete," "MEP installations complete").
Purpose:
- Allows invoicing at important milestones
- Generates legal documentation to claim payment upon completion of phases
- In the event of disputes, it proves compliance with contractual stages
Final or settlement certification
Issued after all work has been completed and the final quality inspection has been carried out.
Contents:
- All work executed (sum of all monthly certifications + additional work not previously certified)
- Measurement corrections (adjustments for overages or underages relative to prior certifications)
- Additional work performed
- Retentions to be released (partial or total, per contract)
- Final net amount to be collected
Time to payment: May take 3–6 months from issuance to final payment, especially where retentions are involved.
Retention release certification
After 6, 12, or 24 months (per contract) from completion, a certification is issued requesting the release of guarantee retentions.
Requirements: Usually requires:
- Report confirming no quality defects
- Satisfactory technical inspections
- Active guarantee certificate
Financial impact: Recovering the 5–10% retained for months. This is significant cash flow.
Certification process step by step
1. Physical progress measurement on site
Weekly or bi-weekly, the site quantity surveyor takes measurements of completed work:
- Measures completed structures: m³ of concrete, kg of steel
- Measures surfaces: m² of cladding, finishes
- Counts units: doors, windows, fixtures
Tools: Tape measure, drawings, checklists, photographs. Documentation: A "measurement report" is generated to accompany the certification.
2. Allocation to budget line items
Each measurement is assigned to a line item of the sales budget (the one agreed with the developer).
Importance: The allocation determines the unit price to apply. An incorrectly assigned measurement can significantly change the certification amount.
Control: The quantity surveyor verifies that the unit price in the budget is consistent with what has been executed. If there are specification changes, they are noted for later adjustment.
3. Calculation of the certification amount
For each certified line item: Measured quantity × Budgeted unit price = Amount
Accumulation: All amounts for line items measured during the month are summed.
Example:
|
Line item |
Budget (€) |
Measurement (%) |
Quantity |
U.P. (€) |
Amount (€) |
|
Structure |
300,000 |
40% |
120 m³ |
2,500 |
300,000 |
|
Walls |
200,000 |
60% |
1,200 m² |
166.67 |
200,000 |
|
Finishes |
150,000 |
0% |
0 |
|
0 |
|
TOTAL |
650,000 |
500,000 |
4. Application of retentions and guarantees
In Spain it is standard to apply a guarantee retention (5–10% of the certified amount) which is released 12 months after project completion.
Types of retentions:
- Guarantee retention: 5–10%, released 12 months after project completion
- Quality retention: In some contracts, an additional retention if defects are found (typically 3–5%)
- Non-compliance retention: If there are delays, some contracts apply penalties (0.5% per day)
Calculation:
Gross certification amount: €500,000 Guarantee retention (10%): −€50,000 Net amount: €450,000
5. Issuance of the certification document
The quantity surveyor drafts an official document that includes:
Heading:
- Project name
- Validity period
- Certification number (e.g., "Certification no. 3")
- Date of issuance
Body:
- Table of line items with measurements, prices, and amounts
- Retention calculations
- Net amount to be collected
- Quantity surveyor's certification: "I certify that the works indicated have been executed in accordance with the project specifications and technical requirements"
Supporting documentation:
- Detailed measurement report
- Photographs of completed work
- Quality control reports
- Material delivery notes
6. Validation by the supervising quantity surveyor
On large projects, a quantity surveyor appointed by the developer validates the certification.
Process:
- Reviews measurements (may request re-measurement if in doubt)
- Verifies compliance with specifications
- Approves or rejects the certification in full or in part
Timeframe: Typically 15–30 days.
7. Invoicing the developer
Once the certification is validated, you issue an invoice to the developer for the net amount.
Requirements:
- Invoice number and date
- Tax ID (CIF/NIF) of issuer and client
- Breakdown by line item
- Retentions and taxes
- Reference to the progress certification
VAT: In Spain, VAT at 21% is applied to the net amount.
8. Payment follow-up
From invoice issuance to actual payment:
- Month 1 (day 1): Validated certification is issued
- Month 1 (day 10): Invoice is issued to the developer
- Month 2 (day 10): 30-day payment deadline expires, payment expected
- Month 2 (day 20): Payment received
In practice: Delays are common. It is typical to wait 60–90 days between certification and payment.
Certification to subcontractors
If you use subcontractors, you must issue certifications to your subcontractors for the same line items.
Subcontracting Act:
- Pay subcontractors within a maximum of 15 days of the developer's certification
- Do not withhold unjustified percentages
- Pass on the guarantee retention: maximum equal to what the developer applies
Example:
Developer certification: €100,000 Developer retention: €10,000 Your collection: €90,000
Subcontractor certification: €100,000 Maximum retention: €10,000 Subcontractor payment: €90,000
Specific features of certifications in Spain
- Subsidized housing (vivienda protegida) projects: 30–60 day payment terms, retentions up to 15%, slow release
- Renovation and rehabilitation projects: measurements of work to be done, final adjustments, additional works
- Risk-based construction projects: provisional measurements, periodic certifications, meticulous documentation
Common mistakes in certifications
- Measuring without linking to the budget
- Specification changes not documented
- Certifying before receiving delivery notes
- Inconsistent retentions
- Failure to document measurements
Tools to improve the certification process
- On-site documentation: geotagged photos, drones, mobile apps
- Management software: BIM, construction management, change control
- Processes: regular validation, coordination meetings, digital filing
How Trowel helps you with certifications
- Measurement management: automatic linking, measurement reports, automatic calculation, history
- Certification management: formal issuance, retention calculation, supporting documentation, certification status
- Payment tracking: invoicing integration, delay alerts, delinquency analysis
- Subcontractor certifications: automatic issuance, retention control, deadline tracking
- Analysis and reports: progress vs. budget, reconciliation, gap analysis, profitability reports
With Trowel, certifications that used to take days are generated in minutes, reducing errors and accelerating payments.
Request a demo and see how Spanish construction companies are streamlining their certification and payment cycle.
