If you're planning to renovate, extend or refurbish a property in Portugal, one of the first questions is always the same: how much does the structural stability project cost? The honest answer is "it depends" — but it depends on concrete things, not on how much the company thinks it can charge you. I'll explain exactly what those are.
What a structural stability project actually is
It's the technical document that calculates whether your property's structure — foundations, columns, beams, slabs — can take what you want to do to it: opening up a wall, adding a floor, reinforcing a wall. It can only be signed by an engineer registered with the Order of Engineers, with the declaration of responsibility that comes with it. Without this document, your planning permission process simply doesn't move forward.
Real prices by property type
These are market reference figures for Portugal for 2025–2026, engineering fees (they do not include local council fees):
| Property type | Typical range | What it usually includes |
|---|---|---|
| Single-family house | €800 – €1,800 | Calculations + report + declaration of responsibility |
| Flat in a block | €1,000 – €2,500 | Calculations + coordination with the building's management |
| Whole building | From €5,000 | Overall calculations + drawings per unit |
| Structural reinforcement | From €400/m² | Steel, reinforced concrete or carbon fibre, depending on the case |
Notice that structural reinforcement isn't quoted per property — it's quoted per m² of area worked on, because the real cost depends on how much material and labour will actually be used, not on the total size of the house.
What's included in the price (and what's often missing from cheaper quotes)
A proper structural stability project always includes three things. If a quote doesn't mention all three, the "cheaper" price may end up costing you more later:
- Calculation report — the figures and structural checks under the Eurocodes, not just the final result.
- Technical drawings — the technical plans the council and the builder will use on-site.
- Declaration of responsibility — the signature of the registered engineer who is legally accountable for the calculations.
Why this matters now more than ever: since the new SIMPLEX Urbanístico reform, the local council no longer evaluates the structural stability project — it accepts it on the cover of the declaration of responsibility. A project without that proper signature, or from an unregistered technician, gives you no protection at all.
Why the same service has such different prices between companies
You've probably noticed that asking three companies for the "same" quote gets you three very different numbers. The most common reasons:
- The property's real complexity — an old building with unknown foundations requires more study than a recent build with the original design available.
- What's left out — some charge only for the calculations and leave the descriptive report or the declaration of responsibility as an "extra".
- Who signs it — a registered engineer with professional civil liability insurance costs more than someone without registration with the Order — and that's exactly the difference that protects you legally.
The simplest rule: always ask for a fixed, itemised quote in writing, never a figure given over the phone. If the quote doesn't say exactly what it includes, ask before signing.
Want a figure for your specific case?
The figures above are market reference points — the exact price depends on the area, the property type and the city. Use our quote calculator to generate an itemised quote by chapter and line item in one minute, or talk directly to the team on WhatsApp for a free assessment.