Security · compliance
The law, plainly written into the engine.
Greek property management has a body of law that most software ignores or fudges. Nestio's allocation engine implements the Π.Δ. 27/1985 formulas exactly, validates per-mille totals on every save, and preserves source documents across edits — so a passing audit is the default, not the exception.
Compliance posture, in numbers.
1000‰
Σ shares enforced
server-side
3 / 9
Π.Δ. methods
autonomous heating
EU
Data hosting
Supabase EU region
Immutable
Audit trail
bills · shares · periods
The Decree
Where it comes from, in three lines.
Π.Δ. 27/1985 · ΦΕΚ A' 11 / 14-2-1985 · Articles 1–3
Greek heating-cost allocation, by Presidential Decree.
The Decree fixes the formula a Greek building must use to split heating costs between fixed (engineering) and variable (consumption) shares. Nestio implements the three autonomous methods with the exact fᵢεᵢ + (Mᵢ / ΣMⱼ) × E_var structure — no rounding, no fudge, traceable per apartment.
Five compliance surfaces.
Π.Δ. 27/1985 — heating allocation
Three of the nine allocation methods (autonomous_hours, autonomous_energy, autonomous_volume) implement the fixed-plus-variable formulas from the Decree exactly as specified.
Σ shares = 1000‰ enforcement
Every per-mille share update is validated server-side. Buildings whose shares don't sum to exactly 1000‰ cannot be saved — the law expects exact totals.
Source-document trail
Every share value carries a source — deed, engineering study, or assembly decision — preserved across edits for legal traceability.
Reserve fund treatment
Operating and reserve ledgers are physically separate. Transfers between them are explicit records, never silent — required for clean assembly reporting.
GDPR · data protection
Resident PII is row-level secured per organisation. Data Processing Addendum available for offices that need one. Data retention configurable.
“The autonomous-heating formulas (autonomous_hours, autonomous_energy, autonomous_volume) implement the Decree's fixed + variable structure exactly: fᵢεᵢ + (Mᵢ / ΣMⱼ) × E_var.”
Three methods, one Decree.
autonomous_hours
cost_i = fᵢεᵢ + (Ωᵢεᵢ / Σ Ωⱼεⱼ) × E_var — fixed share by engineering coefficients + variable by hour-meter reading.
autonomous_energy
cost_i = fᵢεᵢ + (Mᵢ / Σ Mⱼ) × E_var — fixed share + variable by calorie meter (kWh).
autonomous_volume
cost_i = fᵢεᵢ + (Mᵢ / Σ Mⱼ) × E_var — fixed share + variable by litre / volume meter.
GDPR & operational security.
- Row-level security per org · Supabase RLS
- Encrypted gateway credentials · AES-256
- Encrypted secrets at rest · Vault
- TLS 1.3 in transit · everywhere
- Audit trails on bills + payments · immutable
- Audit trail on share updates · with source doc
- Audit trail on period unlocks · auditor-friendly
- Data Processing Addendum · available on request
- Data export on offboarding · CSV + PDFs
- Data deletion on offboarding · verified
- Resident PII isolated per org · RLS
- EU-region data hosting · Supabase EU
The passport an auditor wants to see.
- ●EU-region hosting
- ●AES-256 at rest
- ●TLS 1.3 in transit
- ●Row-level tenant isolation
- ●Immutable audit trail
- ●Offboarding export · CSV + PDF
- ●DPA on request
The questions auditors ask.
- What happens if shares don't sum to exactly 1000‰?
- Save fails server-side. The error names which apartments are off and by how much — the office can't push a building into a bad state by mistake.
- Can I see why a share value changed?
- Yes. Every share update preserves its source — deed reference, engineering study, or assembly decision — and history is queryable per apartment.
- Where is the data physically stored?
- EU region only, on Supabase EU infrastructure. We do not replicate to non-EU regions.
- Do you offer a Data Processing Addendum (DPA)?
- Yes — available on request. Typical Greek-office DPA terms apply; we can review or counter-sign your template.
Walk a passing audit, on the call.
Bring an auditor's checklist; we'll show you the per-mille validation, the heating formula trace, and the share-history record on a real building.