Have you ever heard of AS-BUILT and been confused? In fact, this happens frequently. In many cases, the term is even confused with original design or final design. However, this association is incorrect. In practice, AS-BUILT has its own specific and absolutely critical function for any building.
During construction, changes are inevitable. For example, a pipe that was planned for a certain location ends up being moved. Similarly, walls are repositioned and structural reinforcements are added. These decisions, therefore, arise from technical, construction, or operational reasons.
The problem arises, however, when these alterations are not documented. In this context, no one knows exactly how the building was constructed. As a direct consequence, maintenance becomes complex. Furthermore, future renovations pose structural risks. Similarly, real estate transactions may face significant legal obstacles.
Therefore, in this article you will understand what AS-BUILT documentation is, why it is essential, how it is prepared, when it should be delivered, and what the difference is between AS-BUILT documentation and the original project. Thus, in the end, it will become clear why no building should be delivered without its complete AS-BUILT documentation.
What is AS-BUILT?
AS-BUILT is the set of technical drawings that faithfully represents how the building was actually constructed. In other words, it does not describe the intended design, but rather the executed reality.
The term comes from English. “"as built"”, which literally means “"as built"”. Therefore, this is the final technical record of the work, after all the adaptations made in the field.
Formal Definition
According to NBR 6492, The AS-BUILT drawing is a graphical representation of the completed project. Furthermore, this representation must include all changes, adaptations, and solutions implemented during construction that differ from the original design.
What does an AS-BUILT contain?
For the AS-BUILT drawing to fulfill its purpose, it needs to be complete. Therefore, it must include:
- Floor plans with actual layout and measured dimensions.
- Cuts and elevations with correct heights and thicknesses.
- Technical drawings for hydraulics, electricity, gas and ventilation.
- Construction details effectively executed.
- Photographic record before coating application.
Thus, these elements ensure technical traceability, operational safety, and reliability throughout the building's lifespan.
Practical Example
In the original project, for example, it states:
- Gas column projected at position X
- Sewer pipe planned at depth Y
However, during the execution of the work:
- A rock is identified at location X.
- Consequently, the gas column is displaced 2 meters.
In this scenario, the AS-BUILT documentation accurately reflects this change. This way, future interventions will know exactly where the piping is located, preventing errors.
Why is the AS-BUILT important?
Although often treated as a mere formality, the AS-BUILT is, in practice, an essential document for the entire life cycle of the building.
1. Safety in Maintenance
During maintenance, technicians need to know exactly where pipes, beams, and structural elements are located. If they only consult the original blueprints, the risk of error is high.
As a result, improper drilling, structural damage, and even accidents can occur.
Real risk: interventions in incorrect locations due to lack of reliable information.
2. Future Reforms
Before any renovation, it's essential to know:
- Where are the facilities located?
- Which walls are structural?
- What is the actual thickness of the elements?
The original design, however, may not reflect the final execution. The AS-BUILT, on the other hand, represents reality.
Real risk: reforms that compromise the structure due to a lack of accurate information.
3. Sale of Property
During sales processes, engineers often compare design and execution. When the as-built documentation doesn't exist, it becomes necessary to redo all the measurements.
As a result, additional costs arise between R$ 5,000 and R$ 15,000, in addition to delays in the negotiation.
4. Regularization with the Fire Department
Furthermore, verification of the actual location of fire hydrants, escape routes, and safety systems depends directly on the AS-BUILT documentation.
Real risk: difficulty in obtaining approval or even a halt to construction.
5. Warranty and Technical Responsibility
In cases of structural pathologies, the AS-BUILT documentation allows for the identification of causes and responsibilities. Without this document, the technical investigation is compromised.
AS-BUILT vs. Original Project
This distinction, therefore, needs to be absolutely clear.
Original Project
- Prepared before the work
- It represents the intention of the project.
- Based on calculations and standards
- It may be subject to adjustments during execution.
AS-BUILT
- Prepared after execution.
- It represents the constructed reality.
- Based on actual measurements
- Document all changes.
| Aspect | Original Project | AS-BUILT |
|---|---|---|
| Moment | Before the work | After the work |
| Base | Specifications | Actual measurements |
| Precision | Approximate | Exactly |
| Purpose | Construction | Maintenance and operation |
AS-BUILT Creation Process
Creating an AS-BUILT drawing doesn't just mean copying the original design. On the contrary, it's a structured technical process.
Phase 1: Preparation
During the construction process, the following should also be recorded:
- Project changes
- Changes in materials
- Solutions adopted in the field
- Photographs of the exposed structure.
This step, therefore, is crucial. Conducting this survey later makes the process much more complex and costly.
Phase 2: Field Measurements
After the completion of the work:
- Precise measurements are taken.
- The installed systems are located
- The data is compared with the original project.
Typical timeframe: 2 to 3 weeks for an average building.
Phase 3: Technical Drawing
Based on the measurements:
- The plants are updated.
- Cuts and details are generated.
- The systems are documented.
Typically, CAD or BIM tools are used.
Phase 4: Validation
Finally, the engineer in charge:
- Check the measurements.
- Verify information with the construction company.
- Adjusts inconsistencies
- Issues the final documentation.
What Cannot Be Missing in an As-Built
Floor Plans
They must show the actual dimensions, the constructed structure, and the plumbing and electrical points.
Vertical Cuts
They should indicate the ceiling height, slab thickness, and beam height.
Elevations
They should show the total height and the actual facades.
Technical Systems
Plumbing, electrical, gas, and ventilation systems must be documented as executed.
Construction Details
They should register solutions that were not originally planned.
Photographic Record
Photos of the structure before the cladding is applied are essential and irreplaceable.
When Should the As-Built Drawings Be Delivered?
The best practice is to deliver the As-Built drawings along with the occupancy permit. This ensures complete documentation from the start of occupancy.
Thus, we obtain:
- Ease of maintenance
- Operational safety
- Lower legal risk
When delivery is delayed, risks and costs increase significantly.
Legal Responsibility
- Construction company: responsible for delivery
- Real estate developermust ensure receipt
- Owner (renovations)You must update the AS-BUILT
As-Built Costs
During the Construction
- Average cost between R$ 8 thousand and R$ 15 thousand
- This represents approximately 0.3% to 0.5% of the construction cost.
After the Work
- It can reach R$ 18 thousand.
- Furthermore, it is more time-consuming and complex.
Therefore, executing the AS-BUILT drawings during construction is always more efficient.
Difference Between As-Built and Other Documents
AS-BUILT x As Executed
- AS-BUILT: technical drawings
- As Executed: Descriptive Report
AS-BUILT vs. Renovation Project
- AS-BUILT documents the existing
- Reform project proposes changes
Related Standards
- NBR 6492 – Graphic representation
- NBR 15.575 – Performance standard
- Municipal legislation and requirements of the Fire Department
Conclusion
AS-BUILT is the definitive technical record of the building. While the original design expresses the intention, the AS-BUILT documents the constructed reality.
Therefore, it is indispensable for:
- Safe maintenance
- Correct reforms
- Property appreciation
- Legal certainty
Therefore, if you are buying a new property, demand the AS-BUILT drawings. Similarly, if you intend to renovate, this should be the first document you review.
