What to expect
| Typical duration | Design 3–8 weeks · assessment of an existing building 2–4 weeks |
|---|---|
| Cost band | Figures live in the cost index |
| Permit required | The structural file is part of the permit |
| Seasonal constraint | Not seasonal |
What the engineer is responsible for
- The structural design and calculations, including seismic. See seismic design.
- Foundation design, based on what the ground investigation found rather than on assumption. See volcanic soil foundations.
- Assessment of existing structure where new work attaches to it, or where there is evidence of movement.
- Signing the structural file for the permit, which carries statutory responsibility.
- Statutory supervision during construction, where they hold the επιβλέπων μηχανικός role — confirming the work follows the approved design.
Three genuinely difficult problems on this island
- Foundations in variable ground
- Depth to competent material changes across a plot, and old fill and quarry backfill are common. The engineer designs from the investigation; where there is no investigation they are designing from an assumption, which is why we push hard for trial pits.
- Old masonry
- Assessing a stone-and-vault building means judging a structure with no drawings, unknown foundations and a century of alterations. It is skilled work and it is not something a builder can substitute for.
- The junction between old and new
- The most common structural problem on Santorini renovations. Two structures with different stiffness and different foundations, joined without provision for differential movement. The engineer decides whether to tie or to separate. See extensions.
When you need an engineer and not a builder
It is worth being explicit about this, because owners frequently ask us for reassurance we should not give.
- Any crack you are worried about, particularly diagonal cracking at openings or separation at a corner. See structural cracks.
- Any wall that has moved, leaned or bulged.
- Before removing any wall in a masonry building, or any opening in a vault.
- Before loading a vault or an old floor with anything substantial — a terrace, a hot tub, a heavy stone finish.
- Any movement in ground near a caldera edge or above a retaining structure.
- Before buying a property with visible structural concerns, which is much better money than after.
The supervision role, and why it matters on site
The supervising engineer confirms the work follows the approved design. In practice the checks that matter are the ones that cannot be undone.
- Reinforcement inspection before every pour, particularly at beam-column joints where the confinement detailing is congested and where it is most tempting to simplify.
- Cover checks — spacers in place, reinforcement not displaced by someone standing on it.
- Foundation inspection against what the ground actually presented when it was opened, which is not always what the investigation predicted.
- Any change on site referred back rather than decided in the moment.
We programme these inspections into the sequence rather than treating them as an interruption. A pour that has to wait a day for an inspection is a day; a pour that happened without one cannot be checked afterwards.
Questions people actually ask
Do I have to appoint an engineer separately?
Yes, and it is better that way. Their statutory responsibility is to you, and their independence from the contractor is what makes the sign-off meaningful.
Can you recommend an engineer?
We can suggest people we have worked with, and you appoint them directly. We deliberately do not take a fee for that introduction.
How much does a structural assessment cost?
Set by the engineer and dependent on the building. Against the cost of either unnecessary strengthening or an unrecognised problem, it is consistently good value — particularly before a purchase.
My builder says the wall can come out. Is that enough?
No. In a masonry building an internal wall is frequently carrying load or providing lateral stability. That is an engineer's call, and a builder saying otherwise is giving you an assurance they cannot stand behind.
What is the difference between the designing engineer and the supervising engineer?
The designing engineer produces and signs the structural design. The supervising engineer confirms during construction that what is built follows it. They can be the same person and often are.