Structural engineering: define the assessment, structure and design required
Before altering a building or adding a load, you need to understand how the existing or proposed structure responds. Services can include an initial assessment, calculations, detailed design and agreed inspections. A clear commission separates the required conclusions from subsequent construction work.
Describe the proposed change or question
Identify what needs changing, installing or checking. A wall opening, roof alteration and heavy equipment on a floor need different information. New construction involves a structural concept and its development.
Existing cracks, deformation or questions about a construction can also prompt assessment. Describe known observations without diagnosing their cause or load capacity. The professional establishes the investigation required.
| Reason | Assessment to define |
|---|---|
| Change a wall | Affected walls, openings and proposed arrangement. |
| Additional load | Object, use and proposed position. |
| New structure | Project, construction and design stage. |
| Review existing construction | Components, observations and questions. |
| Second review | Existing calculations and assumptions to check. |
Review drawings against actual conditions
Architectural drawings, structural calculations, construction records and previous alterations can matter. Identify available documents and their status. A drawing does not automatically show every subsequent change or actual construction detail.
Existing components may need a visit, recording or further professional investigation. A photograph or the building’s age cannot determine this alone. Agree how missing information will be obtained and which assumptions remain.
An initial enquiry is possible without complete records. Describe the purpose and affected areas. The professional should explain what additional information is required for a calculated conclusion.
Have structural function and loads assessed
An internal wall is not dispensable merely because of its position or limited thickness. Altering a component involves its interaction with floors, other walls and the remaining structure. Structural function and necessary measures require professional assessment.
Proposed use and installation matter for additional equipment. Product information helps but does not replace assessment of the supporting construction and load transfer. Empty weight is not always the load in operation.
A general distributed load in documents is not blanket approval for any object at any location. Have position, supports, existing construction and use assessed. The study should identify the limits of its conclusions.
Separate assessment, calculations and detailed design
Initial advice can identify suitable investigations or alternatives. A written opinion, calculations and detailed construction drawings are different deliverables. Define the result your next decision requires.
If strengthening or other changes are necessary, their detailed design is a further stage. It may include details, interfaces and coordination with designers and contractors. A recommendation is not already commissioned construction work.
Earthquakes, vibration or unusual structures can require specific expertise. Ask for appropriate experience and the responsible professional. A general commission does not automatically assess the entire building for every risk.
Coordinate approvals and execution before intervention
A technical assessment does not automatically replace owner consent, official enquiries or checks for services and pollutants. Agree who handles these interfaces. Plan changes with the professionals before altering components or adding loads.
Do not test capacity yourself by trial loading or removing components. Necessary surveys, openings and investigations require professional organisation. Known observations can be described in the enquiry.
During construction, use approved drawings and agreed inspections. Clarify reporting of changes and any commissioned visits or later checks. Calculations do not automatically include continuous construction supervision.
Compare fees by responsibilities and deliverables
A limited review differs from structural design for an entire project. Fees depend on available information, complexity, investigations, calculations and drawings. Alternatives and later changes can add work.
Ask for included visits, meetings, reports and drawing deliveries. Clarify time charges or fixed fees and authorisation of further investigations. A low-cost initial opinion is useful only if it supplies the result required.
Construction, strengthening, materials, permission fees and other specialist checks are separate unless expressly included. Travel, expenses, third-party services and VAT belong in the comparison. Different commissions cannot establish a reliable Swiss average.
| Cost item | Check in the quotation |
|---|---|
| Information | Drawing review, recording and further data. |
| Engineering | Assessment, calculations and alternatives. |
| Documentation | Opinion, report and detailed drawings. |
| Additional services | Investigations, coordination or visits. |
| Construction | Separate execution and other trades. |
| Total | Travel, expenses, third-party work and VAT. |
Prepare an understandable enquiry
Show the project you want to pursue. You do not need to determine capacity, structural function or the technical solution yourself.
- Project. Describe the change, additional use or reason for review.
- Components. Identify affected areas and linked interventions.
- Information. Explain drawings, calculations and product details.
- Deliverables. Separate advice, calculations, reporting and design.
- Interfaces. Identify designers, contractors and known outstanding approvals.
Reach a coordinated technical basis
The work depends on the task and available information. Outstanding assumptions should remain visible before an execution decision.
- Explain the question. Summarise the proposal, areas and observations.
- Clarify information. Agree documents, visits and investigations.
- Compare quotes. Compare matching assessment and design scope with full fees.
- Assess and design. Prepare agreed calculations and deliverables professionally.
- Define the next steps. Clarify limitations, approvals and possible construction.
Frequently asked questions
Do I need to know whether a wall is load-bearing?
No. Describe the proposed change and available records. The wall’s function is part of the professional assessment. Position, thickness or an earlier alteration alone cannot authorise removal.
Can a hot tub or heavy equipment be assessed?
Yes, a project-specific assessment can be commissioned. Identify position, use and available product information. The assessment must consider construction and load transfer; empty weight or a general distributed load alone is insufficient.
Can I enquire without structural drawings?
Yes. Identify missing records. Visits, recording or further investigations may be needed and their scope should be agreed.
Does a report automatically include strengthening and construction?
No. Opinion, detailed design and execution are separate. Clarify drawings, coordination, inspections and who undertakes construction.
How much do structural services cost?
Compare review, calculations, investigations, reporting, drawings and included appointments. Construction, specialists, expenses and VAT need separating. A price for another scope is not a reliable average.
Does an assessment still apply after a project change?
Not automatically. A different product, position or altered components can change the information. Have the validity of the conclusions and any necessary update reviewed.
