Fire regulations for battery energy storage (BESS) in Poland: distances and permits
A guide by AIESS engineers based on the draft Polish technical-conditions regulation of 6 August 2026 and the Building Law in force. Every statement is labelled: draft text, law in force, AIESS interpretation or insurer practice.
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The key facts in 30 seconds
A free-standing battery energy storage system up to 300 kWh must stand at least 4 m from a building, 300–2000 kWh – 8 m, 2000–5000 kWh – 15 m, above 5000 kWh – 20 m (from ZL, IN and PM buildings with fire load Q ≤ 1000 MJ/m²). These values come from the draft Polish technical-conditions regulation (WT) of 6.08.2026 (§ 283 sec. 16–21), which is not yet in force – until about 20.03.2028 the 2002 regulation applies, with no BESS rules. The permit route already follows the Building Law in force: up to 30 kWh no formalities, up to 2000 kWh a notification with a fire-approved design, above 2000 kWh a building permit.
- Draft regulation – textAlways at least 4 m from windows, doors, skylights and ventilation openings of a building, and 1.5 m from the plot border.
- Draft regulation – textStorage units closer than 3 m to each other count as one – capacities add up, unless separated by a REI 120 wall projecting 0.3 m.
- Draft regulation – textFrom a forest (Ls land > 0.5 ha): 8 / 12 / 22.5 / 30 m for the four capacity classes; fire walls do not shorten it.
- Draft regulation – textNext to the building it supplies (closer than 4 m or on its wall): at most 120 kWh in total; on a flat roof at most 600 kWh.
- Law in forceStorage above 30 kWh needs a design approved by a fire-safety expert and a notice to the State Fire Service (PSP) with a plan for rescuers.
- Insurer practiceInsurers (PZU, SALTUS) often require at least 10 m from buildings or a REI 120 wall – more than the 4 m in the draft for a small cabinet.
Legal status: what applies today
- Law in forceThe draft regulation of 6.08.2026 has not been signed or published; the planned entry into force on 20.09.2026 did not happen.
- Law in forceFor 18 months from 20.09.2026 (until about 20.03.2028) the previous technical conditions apply – WT 2002. The investor declares that the design follows the previous rules.
- Law in forceWT 2002 has no provisions on energy storage. Requirements are agreed with a fire-safety expert; the Interior Ministry treats Li-ion storage as PM (production/storage) zones.
- Draft regulation – textThe wording of § 283 sec. 16–21 has been unchanged since the 24.04.2026 version, and the ministry, answering parliamentary question 19406, does not plan to change the 600 kWh limit.
- AIESS interpretationAIESS designs layouts to the draft – the best available "future standard" and a strong argument in fire approvals. Always check whether the regulation has been published before filing.
Storage capacity classes
A BESS is a storage system with secondary cells and a nominal capacity above 2 kWh (§ 311 sec. 1). Distances depend on the total nominal capacity of the group. Thresholds are "not greater than": 300.0 kWh is still the ≤ 300 kWh class.
| Class | Nominal capacity | Treated as a PM building with Q | Typical product |
|---|---|---|---|
| ≤ 300 kWh | > 2 to 300 kWh | – (fixed 4 m) | 261 kWh cabinet, 120 kWh hybrid |
| 300–2000 kWh | > 300 to 2000 kWh | Q ≤ 1000 MJ/m² | 2–7 cabinets side by side |
| 2000–5000 kWh | > 2000 to 5000 kWh | 1000 < Q ≤ 4000 MJ/m² | 2.5–5 MWh container |
| > 5000 kWh | above 5000 kWh | Q > 4000 MJ/m² | 2 containers side by side |
- AIESS interpretationWe use the nominal capacity from the datasheet, not the usable capacity (DoD).
Distance from a building
Storage above 300 kWh is treated as the wall of a PM building with a fire load density Q that depends on capacity, and the distance is read from the table in § 283 sec. 1. Storage up to 300 kWh stands at least 4 m from a building. Base values, without corrections:
| Neighbouring building ↓ / storage → | ≤ 300 kWh | 300–2000 kWh | 2000–5000 kWh | > 5000 kWh |
|---|---|---|---|---|
| ZL – residential, office, retail | 4 m | 8 m | 15 m | 20 m |
| IN – livestock | 4 m | 8 m | 15 m | 20 m |
| PM, Q ≤ 1000 MJ/m² | 4 m | 8 m | 15 m | 20 m |
| PM, 1000 < Q ≤ 4000 MJ/m² | 4 m | 15 m | 15 m | 20 m |
| PM, Q > 4000 MJ/m² | 4 m | 20 m | 20 m | 20 m |
| Window, door, skylight, ventilation opening | 4 m | 4 m | 4 m | 4 m |
- Draft regulation – textThe distance is measured horizontally, at the nearest point, from the storage enclosure.
- AIESS interpretationWe measure from the outer outline of the enclosure including protruding parts (HVAC unit, canopy, vent panels).
- AIESS interpretationA transformer station counts as PM under § 220 sec. 3, but according to the Supreme Administrative Court (II OSK 704/24) a compact container substation is a structure, not a building – then the distance follows IEC 61936-1 (e.g. 3 m for 1000–2000 l of oil).
Distance corrections (storage above 300 kWh)
Corrections apply to distances from buildings, in this order:
| Condition | Change | Basis |
|---|---|---|
| The neighbouring wall facing the storage is not non-flammable (NRO) | × 1.5 | § 283 sec. 2 pt 1 |
| The neighbouring roof covering is not NRO (no BROOF(t1)) | × 1.5 | § 283 sec. 2 pt 2 |
| The condition applies to both objects (storage enclosure also not NRO) | × 2 | § 283 sec. 2 |
| Neighbouring wall has fire class E on 30–65% of its area (many windows, gates) | × 1.5 | § 283 sec. 3 |
| Neighbouring wall has fire class E on less than 30% of its area | × 2 | § 283 sec. 4 |
| An explosion-hazard room in either object | min. 20 m | § 283 sec. 5 |
| Sprinklers in all fire zones of the neighbour along that wall | × 0.75 (last) | § 283 sec. 6 |
d = max(d_base × k_NRO × k_openings; 20 m if explosion hazard) × 0.75 (if sprinklers), then at least 4 m from openings.
- Draft regulation – textSec. 16 refers only to sec. 1–6, so the 50% reduction (sprinklers in both buildings, sec. 7) and the 25% reduction for § 224 buildings (sec. 10) do not apply.
- AIESS interpretationA steel cabinet or container enclosure is NRO. A non-NRO wall and roof of the same building give × 1.5, not × 2.25.
- AIESS interpretationWe do not apply corrections to the fixed 4 m for storage up to 300 kWh.
- AIESS interpretationSuppression inside the container (aerosol, FK-5-1-12) does not give the 25% reduction – only sprinklers in the fire zones of the neighbouring building count.
The 3 m rule: when several units count as one
- Draft regulation – textFree-standing storage units less than 3 m apart are treated as one unit with a capacity equal to the sum.
- Draft regulation – textThis does not apply to units separated by a fire wall of at least REI 120 projecting at least 0.3 m vertically and horizontally beyond their outline.
- AIESS interpretationSpacing cabinets ≥ 3 m apart follows directly from the text, so each 261 kWh cabinet stands 4 m from a building. A chain A–B < 3 m and B–C < 3 m is cautiously treated as one group A+B+C.
- AIESS interpretationSpacing does not change the Building Law route: cabinets on a shared PCS / EMS are one storage system (sum of kWh).
Plot border and forest
From any plot border – at least 1.5 m. From the border of an unbuilt building plot – half the distance to a hypothetical building: a ZL building where there is no local zoning plan (MPZP), otherwise as zoned (for PM, 1000 < Q ≤ 4000 is assumed).
| Storage | Any border | Unbuilt building plot – no MPZP / MPZP ZL, IN | Unbuilt building plot – MPZP PM |
|---|---|---|---|
| ≤ 300 kWh | 1.5 m | 2 m | 2 m |
| 300–2000 kWh | 1.5 m | 4 m | 7.5 m |
| 2000–5000 kWh | 1.5 m | 7.5 m | 7.5 m |
| > 5000 kWh | 1.5 m | 10 m | 10 m |
A forest is Ls land in the land register or forest in the zoning plan, forming a complex above 0.5 ha. The distance is calculated as from the wall of a ZL building with a non-NRO roof (hence × 1.5).
| Storage | Distance from the forest edge | Calculation |
|---|---|---|
| ≤ 300 kWh | 8 m | fixed value (sec. 21 sent. 2) |
| 300–2000 kWh | 12 m | 8 m × 1.5 |
| 2000–5000 kWh | 22.5 m | 15 m × 1.5 |
| > 5000 kWh | 30 m | 20 m × 1.5 |
- Draft regulation – textThe rules on land strips and fire walls (sec. 11–13) do not apply next to a forest.
- AIESS interpretationA built-up plot, farmland without building rights or a road: 1.5 m from the border plus the distance to existing buildings.
- AIESS interpretationHalf the distance from an unbuilt plot is calculated without corrections – the hypothetical building has an "ideal" wall.
Storage next to a building, on a wall and on a roof
| Parameter | Value |
|---|---|
| Total closer than 4 m to the building and on its wall | ≤ 120 kWh |
| Total on a flat roof | ≤ 600 kWh |
| Group on a wall more than 2 m above ground | ≤ 30 kWh |
| Group on a flat roof | ≤ 120 kWh |
| Spacing between groups | 1.5 m horizontally, 3 m vertically (on a roof or an EI 120 wall + 0.3 m) |
| From windows, doors, skylights, ventilation | 1.5 m |
| From escape doors (buildings other than § 224) | 3 m |
| Wall of class A1 or A2,d0 (buildings other than § 224) | 1.5 m around and 3 m above the enclosure |
| From the roof edge, hatches, equipment / from a smoke vent | 1.5 m / 1 m |
| More than 25 m above ground | only on a wall with fixed suppression or on a REI 60 A1/A2,d0 roof |
- Draft regulation – text§ 317 sec. 3 applies to storage installed outside a building closer than 4 m to it, on its wall or on its roof.
- Draft regulation – textInside a building not used only for storage: at most 600 kWh per fire zone; in a flat in a multi-family building: at most 11 kWh and 3.7 kW.
- AIESS interpretationAny cabinet above 120 kWh (e.g. 261 kWh) can only stand free, at least 4 m from a building. Keep two 120 kWh hybrids ≥ 3 m apart – otherwise they form a 240 kWh group.
Procedure: notification or building permit
These rules are already in force (Building Law amendment, Dz.U. 2025 item 1847). They apply to free-standing storage, by nominal capacity.
| Capacity | Route | Fire-safety approval | Notice to fire service | Basis |
|---|---|---|---|---|
| ≤ 30 kWh | no permit or notification | – | – | art. 29 sec. 2 pt 39 |
| > 30 to 300 kWh | notification + site plan (PZT) | site plan fire-approved | yes, with a plan for rescuers | art. 29 sec. 1 pt 40, art. 30 |
| > 300 to 2000 kWh | notification with site plan and architectural design (PAB) | site plan and design fire-approved | yes | art. 29 sec. 1 pt 3c, art. 30 sec. 4bb |
| > 2000 kWh | building permit | general rules (MSWiA 2023) | general rules | art. 28 sec. 1 |
- AIESS interpretationThe Building Law has no aggregation rule. Cabinets on a shared PCS, grid connection or EMS are treated as one storage system. Around 2 MWh, when in doubt, choose the permit route.
- Law in forceAn explosion-hazard room (possible pressure rise > 5 kPa) means 20 m from buildings already today (WT 2002 § 271 sec. 3); the investor, designer or user makes the assessment, and alternative solutions are not allowed.
- Law in forceA container farm may need a fire access road (4 m wide, 100 kN per axle) and firefighting water of 10–20 dm³/s.
- Law in forceNight-time noise at protected areas: 40 dB next to single-family housing, 45 dB next to multi-family and farmstead housing – often stricter than fire rules.
Worked examples
Results come from the same rules engine the AI assistant uses.
261 kWh cabinet next to a factory hall
PM hall, Q = 1500 MJ/m², NRO walls and roof, a gate in the wall facing the storage.
- from building
- 4 m
- from border
- 2 m
- procedure
- notification
Four 261 kWh cabinets side by side (1044 kWh)
PM hall, Q = 800 MJ/m², PIR roof without BROOF(t1), wall with class E on 55% of its area, no sprinklers.
- from building
- 18 m
- from border
- 4 m
- procedure
- notification
5 MWh container on a PV farm next to a forest
Barn (IN) with a timber wall, 12 ha Ls forest, unbuilt building plot zoned PM.
- from building
- 22.5 m
- from forest
- 22.5 m
- from border
- 7.5 m
- procedure
- building permit
3.34 MWh container next to a neighbour’s house
Single-family house (ZL) with a timber façade (non-NRO), ceramic tile roof (NRO).
- from building
- 22.5 m
- from border
- 1.5 m
- procedure
- building permit
Drawings from the draft regulation annexes
AIESS diagrams
Drawings from annexes 3, 11 and 13 of the draft – the geometry of land strips, fire walls and distances from the border.
Beyond the regulation: insurers and standards
- Insurer practicePZU: at least 10 m from buildings (20 m recommended), 6 m between storage units, water of at least 20 l/s.
- Insurer practiceSALTUS (storage > 20 kWh): 10 m from buildings or a REI 120 wall; hydrogen detection at 10% LEL; complexes ≤ 500 m², 10 m apart.
- Insurer practiceFM Global DS 5-33 (04.2026): LFP – 1.5 m from walls with doors or vents, NMC – 4.0 m; containers above 46.5 m² treated as buildings.
- AIESS interpretationNFPA 855 (US) requires 3 m (10 ft) from buildings and borders, reducible to 0.9 m with a fire barrier – the Polish draft is stricter. NFPA arguments and UL 9540A reports are useful in expert opinions.
- Law in forceSince 18.08.2024 stationary storage systems must meet art. 12 of Regulation (EU) 2023/1542 – 11 safety test parameters (Annex V).
- AIESS interpretationBefore finalising a layout, ask the client about their property insurer – a cabinet 4 m from a hall, compliant with the draft, may not meet the policy terms.
Open questions in the draft
Places where the text is ambiguous, with AIESS’s working interpretation and its confidence.
| # | Question | AIESS interpretation | Confidence |
|---|---|---|---|
| Q1 | Is an MV/LV substation a PM building? | Compact container substation – a structure (NSA II OSK 704/24), distance per IEC 61936-1; masonry with indoor operation – cautiously a PM building. | medium |
| Q2 | Is a BESS container an explosion-hazard room (20 m)? | Not automatically – a documented ΔP ≤ 5 kPa calculation decides (gas data from UL 9540A, NFPA 69 ventilation). | medium |
| Q3 | Is a container a building? | No – it is a "free-standing energy storage" (NSA II OSK 975/26: technical infrastructure equipment). | high |
| Q4 | Is ≥ 3 m spacing a legal workaround? | Yes, it follows from the text; chains < 3 m – cautiously one group. | high |
| Q5 | Storage next to a building + another < 3 m from it | Avoid – keep ≥ 3 m between them. | low |
| Q6 | Border with farmland, a road, a built-up plot | 1.5 m from the border (plus distance to existing buildings). | medium |
| Q7 | Building used only for BESS | As a PM building; inside: fire alarm, fixed suppression, groups ≤ 120 kWh. | medium |
| Q8 | Free-standing REI 120 wall between storage and a building | In principle shortens the distance (Annex 13 fig. 3); geometry to be agreed; not for forests. | medium / low |
| Q9 | Corrections for the fixed 4 m (≤ 300 kWh) | Not applied; 4 m from openings still applies. | medium / high |
| Q10 | Class E share in a § 224 building wall | Use the share of openings: > 35% × 1.5, > 70% × 2. | low / medium |
| Q11 | Nominal or usable capacity | Nominal, from the datasheet. | high |
| Q12 | Order of corrections | Multiply sec. 1 × sec. 2 × sec. 3/4, then max with 20 m, finally × 0.75. | medium |
| Q13 | § 285 (buildings on one plot) | Does not cover storage – distances apply to the investor’s own buildings too. | medium |
| Q14 | Emergency switch on a farm without a building | Formally not required; AIESS always installs one (at the gate, AC + DC). | high |
| Q15 | Half distance from a plot – with corrections? | No corrections for the hypothetical building. | medium / high |
| Q16 | Where to measure from | From the enclosure outline including protrusions, horizontally. | high |
| Q17 | PCS / transformer < 3 m from storage | Not aggregated (no batteries); distances per manufacturer. | medium |
| Q18 | Sprinklers and the 25% reduction | Only if every neighbouring zone along the wall is sprinklered; suppression in the BESS does not count. | high |
| Q19 | Aggregation for Building Law thresholds | Shared PCS / EMS = one storage system; 3 m spacing does not change the route. | medium |
| Q20 | What to apply today | Layout per the draft; formally WT 2002, MSWiA 2010/2009, Building Law art. 29–30. | medium |
Frequently asked questions
Sources
Legal acts and official documents behind this guide. Links go to ISAP (Polish Parliament), RCL, gov.pl and EUR-Lex; titles are in Polish.
- Projekt rozporządzenia Ministra Finansów i Gospodarki w sprawie warunków technicznych, jakim powinny odpowiadać budynki i ich usytuowanie (projekt z 6.08.2026), nr RCL 12412604
- Pierwotny projekt rozporządzenia MRiT w sprawie warunków technicznych (9.06.2025), nr RCL 12398903
- Ustawa z 4 grudnia 2025 r. o zmianie ustawy – Prawo budowlane oraz niektórych innych ustaw (Dz.U. 2025 poz. 1847)
- Ustawa z 31 lipca 2026 r. o zmianie ustawy o samorządach zawodowych architektów oraz inżynierów budownictwa oraz ustawy – Prawo budowlane (Dz.U. 2026 poz. 1161)
- Prawo budowlane – tekst jednolity (Dz.U. 2026 poz. 524), art. 9, 28–30
- Komunikat MRiT z 18.09.2026 dotyczący prac nad rozporządzeniem w sprawie warunków technicznych
- Rozporządzenie Ministra Infrastruktury z 12 kwietnia 2002 r. w sprawie warunków technicznych, jakim powinny odpowiadać budynki i ich usytuowanie (WT 2002)
- Rozporządzenie MSWiA z 7 czerwca 2010 r. w sprawie ochrony przeciwpożarowej budynków, innych obiektów budowlanych i terenów (t.j. Dz.U. 2023 poz. 822), § 37
- Rozporządzenie MSWiA z 24 lipca 2009 r. w sprawie przeciwpożarowego zaopatrzenia w wodę oraz dróg pożarowych
- Rozporządzenie MSWiA z 5 sierpnia 2023 r. w sprawie uzgadniania projektu pod względem zgodności z wymaganiami ochrony przeciwpożarowej (Dz.U. 2023 poz. 1563)
- Ustawa o ochronie przeciwpożarowej – tekst jednolity (Dz.U. 2025 poz. 188), art. 6a
- Rozporządzenie Ministra Środowiska w sprawie dopuszczalnych poziomów hałasu w środowisku (t.j. Dz.U. 2014 poz. 112)
- Interpelacja nr 19406 i odpowiedź MRiT z 8.10.2026 (limit 600 kWh, magazyny na zewnątrz)
- Rozporządzenie (UE) 2023/1542 w sprawie baterii i zużytych baterii, art. 12 i załącznik V
- Normy i standardy (płatne, cytowane za opracowaniami): NFPA 855 (2023/2026), UL 9540A, IEC 61936-1, FM Global DS 5-33, PN-EN 13501-1, PN-B-02852:2001
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