Soundproofing an apartment in Montenegro: what the rule requires and what you can check before buying

In residential buildings in Montenegro the equivalent sound level LAeq in the habitable rooms of an apartment must not exceed 30 dBA at night and 40 dBA during the day — with the windows closed. That is Article 5 of the Rulebook on technical requirements for sound protection of buildings against noise.

The rule covers noise from sources inside the building and from the outdoor environment alike: neighbour, lift, pump, street — to the rule it is the same LAeq in your room. How the developer achieves it is not prescribed; the regulation fixes the result and requires that result to be calculated in advance and demonstrated in a separate document — the noise protection report.

Three things worth carrying away from everything below: the figure 30 dBA is for night and for closed windows; the prime in R'w means "in the finished building, with every flanking path of sound included" and not "in the laboratory"; and the duty to confirm the rule by measurement is, for now, suspended in Montenegro.

If you are reading this before a purchase, the shortest useful conclusion is this: ask for the noise protection report. One document answers every question below at once, and whether it exists at all tells you more about a project than any presentation.

The act in force is the "Pravilnik o tehničkim zahtjevima za zvučnu zaštitu zgrade od buke", Official Gazette of Montenegro no. 060/18 of 07.09.2018. It was adopted under Article 72 paragraph 2 of the Law on Spatial Planning and Construction of Structures, issued by the Ministry of Sustainable Development and Tourism, and entered into force on the eighth day after publication (Article 16). Article 15 repealed the earlier "Pravilnik o zvučnoj zaštiti zgrada".

One clarification is worth making here, because it is easy to get wrong: numbers such as 57/14, 25/19 or 140/22 are numbers of the Law, not of the rulebook. If a designer quotes you numbers like these in connection with acoustics, a different document is being discussed. There is only one sound protection rulebook, and it dates from 2018.

The rulebook does not apply to concert halls, cinemas and sound studios (Article 3) — those rooms have their own acoustics and their own problems. Housing is the document's main addressee.

Thirty decibels is very quiet. For scale: a whisper at one metre is roughly in that range. The rule requires your bedroom at night to be quieter than a whisper — with the windows closed and with lifts, pumps and neighbours all running.

During the day 40 dBA is permitted. A difference of 10 dB on the decibel scale does not mean "a third louder" but roughly twice as loud to the ear: the scale is logarithmic, and every 10 dB corresponds to a doubling of perceived loudness. The night limit is therefore substantially stricter than the daytime one, not marginally.

It also matters that LAeq is an equivalent level — averaged over a period of time. A single slammed door almost disappears into it; a pump humming all night enters it in full. The rule captures the background level, not the event. That is one reason complaints about footsteps from above are formally hard to pursue, even though they are exactly what wears people down day to day — more on that below.

There is a second reason the night figure looks strict. The outdoor limit in a residential zone in Montenegro is 45 dB at night (a separate section on this below). The indoor limit is 30 dBA. The 15 dB difference is precisely the work the façade has to do: 45 outside, 30 inside. If the plot sits not in a residential zone but in a road-traffic noise zone, where 55 dB is allowed at night, the façade must already absorb 25 dB — and that is a different construction at a different price. Choosing a street in Bar is therefore also a budget decision about windows.

And an observation from practice: almost nobody judges an apartment on noise during a viewing. Viewings happen in daylight, on a weekday, with the windows shut and the building empty — that is, in exactly the conditions under which every apartment is quiet. We have written before that the most expensive room in an apartment is the bedroom; it should be judged by night, not by midday.

Article 6 sets two groups of limit values:

Minimum airborne sound insulation values — written as R'w (sound reduction index) or DnT,w (standardised level difference). This is about voices, television, music, a barking dog: the sound travels through the air, meets a building element and passes partly through it.

Maximum impact sound pressure levels — L'n,w. This is about footsteps, a chair dragged across the floor, a dropped spoon, a child's ball. Here the sound is generated directly in the structure: a knock on the slab turns the whole slab into a membrane, and you hear it at your place.

The logic of the two signs runs in opposite directions, and this is often confused. For airborne sound, the larger R'w is, the better — it is the number of decibels the element absorbs. For impact sound, the smaller L'n,w is, the better — it is the number of decibels that reaches you. A salesperson who says "we have soundproofing of 55" has to say which of the two quantities is meant, or the sentence means nothing.

And there is a third detail that separates an apartment that works from a handsome data sheet — the prime. Acoustics has Rw without a prime and R'w with one.

Rw without a prime is the laboratory value of the element. The wall was built on a test rig where it is isolated from everything else, and measured there. That is the number in the manufacturer's catalogue.

R'w with a prime is the same thing, but in the finished building, where the wall does not stand in a vacuum but rests on the slab and joins the façade, the screed, the services shaft. Sound does not have to go through the wall: it is enough for it to go around, via the floor slab, via a continuous screed, via shared plaster, via a ventilation duct. Those detours are called flanking transmission.

The practical consequence: a wall with an excellent catalogue value of Rw = 58 dB can deliver R'w = 45 dB in the building if it sits on a continuous screed running from apartment to apartment without a break. The rule asks for R'w. Buying good blocks is therefore not enough — the whole junction has to be designed as a junction. That is precisely the content of the calculation the regulation requires.

Article 7 requires that calculations determining acoustic comfort in the building be carried out at the technical documentation stage, and that their results be presented in the noise protection report, which forms part of the technical documentation. Acoustics, then, is not a wish but a compulsory chapter of the design.

Article 8 divides the analysis into three calculation categories: insulation between two rooms separated by a wall or a slab (horizontally and vertically); façade insulation; noise from building services. And it prescribes the use of the MEST EN 12354 series of standards.

Article 9 spells this out:

- airborne sound within the building — MEST EN 12354-1 - impact sound — MEST EN 12354-2 - external elements of the building envelope (façade) — MEST EN 12354-3

The value of that series lies in exactly what the previous section was about: you do not calculate a single wall, you calculate a building — taking account of the flanking paths through adjoining elements. A design prepared to MEST EN 12354 answers the question "what will be audible in the finished apartment" rather than "which wall is in the catalogue".

Article 10 additionally requires that measures to reduce the noise generated by building equipment be provided for already at the documentation stage — both in the rooms and in the outdoor environment around the building. That covers heat pumps, fans, lift drives, booster pumps: they have to be calculated and isolated, not installed and then observed.

The limit values themselves — minimum values for R'w and DnT,w and maximum values for L'n,w for separating elements — are in Annex 1, tables 2 to 8 (Article 6). Table 1 there also gives permitted noise levels for buildings of other uses besides residential.

An honest limitation we are obliged to state: in the official PDF of the rulebook on the gov.me portal, the annex pages are scanned images with no text layer. The figures in tables 2 to 8 cannot be read from that file by machine, and we will not quote them "from memory" or present values from neighbouring countries' regulations as Montenegrin ones: a number without a source is not a fact but a risk.

The practical conclusion for a buyer: look up the specific required values for your construction type in the annex tables or — more simply and more usefully — in your building's noise protection report. The designer was obliged to enter them there. Asking to see the report settles the question completely and at the same time checks whether it exists at all.

One further requirement from Article 6 can be read without the tables and is worth remembering: a very noisy plant room must not adjoin an apartment. If a transformer station, pump room or machine room abuts a habitable room, that is not "a feature of the layout" but a direct breach of the rule.

Now the most important part, and it is barely written about anywhere.

Article 12 of the rulebook deals with measuring sound insulation in the building: "Mjerenje zvučne izolacije u zgradi sprovodi se u skladu sa standardima koji su dati u Prilogu 2" — measurement is carried out in accordance with the standards given in Annex 2.

And Article 14 says, word for word: "Odredbe člana 12 ovog pravilnika, primjenjivaće se od dana pristupanja Crne Gore Evropskoj uniji" — the provisions of Article 12 shall apply from the day Montenegro accedes to the European Union.

Which means: in Montenegro today the calculation of acoustics at the design stage is mandatory, but verification by measurement of what was actually built is not. The gap between "calculated" and "built" has not yet been closed by law.

This is not a reason to panic and not evidence that every building is bad. Exactly one conclusion follows from it: the only document that says anything today about the noise in your future apartment is the noise protection report in the design. Not the brochure, not the render, not the word of the sales team. And a second: if a developer has commissioned control measurements after completion on their own initiative, that is a voluntary step beyond the rule and deserves separate credit. How to read the design documentation of a Montenegrin project at all we set out in detail in how to check a property in Montenegro.

On EU accession and its timing we wrote separately in the full guide to buying property: no date is set, so nothing can be planned around it — in acoustics or anywhere else.

Since the specific Montenegrin tables cannot be read by machine, it helps to know the order of magnitude usual in the region. The closest example is Croatia, an EU member with a recent document.

Tehnički propis o akustici u zgradarstvu, "Narodne novine" no. 71/2025, adopted on 16.04.2025, published on 18.04.2025, in force on the eighth day after publication. Table C.1.1 for residential and mixed residential-commercial use sets:

- wall between apartments — R'w at least 52 dB - floor slab between apartments — R'w at least 52 dB and L'n,w at most 55 dB - wall to the staircase and corridor — DnT,w at least 42 dB - apartment entrance door — Rw at least 30 dB - windows and balcony doors — Rw at least 30 dB

For windows and doors the Croatian regulation additionally requires the laboratory value to exceed these figures by 2 dB.

We state it plainly: these are Croatian figures, not Montenegrin ones. We give them as a guide to the order of magnitude and as grounds for a specific question to the developer — "what values are in our report, and how do they compare with these". A good designer answers that calmly and in substance.

German experience adds an unwelcome but honest thought to the picture.

Germany applies DIN 4109 "Schallschutz im Hochbau", with part 5 of that standard describing elevated requirements; alongside it the guideline VDI 4100 sets out three sound insulation quality classes.

And the German Environment Agency (Umweltbundesamt) writes about this, word for word: "Allerdings sind auch bei Einhaltung der Mindestanforderungen der DIN 4109 Belästigungen durch Geräusche aus benachbarten Wohnungen oder von gebäudetechnischen Anlagen nicht auszuschließen." — even where the minimum requirements of DIN 4109 are met, disturbance from noise out of neighbouring apartments or from building services cannot be ruled out.

Translated into a buyer's language: the standard is the threshold at which "tolerable" begins, not "quiet". A building built exactly to the minimum breaks nothing and can still disturb. The agency therefore advises explicitly: elevated sound insulation must be agreed while the building is being built — it cannot be added later.

That is probably the most important practical conclusion of this whole text, and it also explains why the conversation about noise has to happen before signing rather than after moving in. We have written before that the most expensive mistake when buying is the one you cannot see; acoustics is its best example.

Everything described so far concerns the building. But there is a second, independent rule — for the environment.

"Pravilnik o graničnim vrijednostima buke u životnoj sredini, načinu utvrđivanja indikatora buke i akustičkih zona i metodama ocjenjivanja štetnih efekata buke", Official Gazette of Montenegro no. 060/11 of 16.12.2011, amended by no. 094/21 of 03.09.2021 — sets limit values by acoustic zone:

- quiet zone in nature — 35 / 35 / 30 dB (day / evening / night) - quiet zone in an agglomeration — 40 / 40 / 35 - zone of elevated noise protection — 50 / 50 / 40 - residential zone — 55 / 55 / 45 - mixed zone — 60 / 60 / 50 - air traffic noise zone — 55 / 55 / 50 - road traffic noise zone — 60 / 60 / 55 - rail traffic noise zone — 65 / 65 / 60

Note the difference between "residential zone" (45 dB at night) and "road traffic noise zone" (55 dB at night) — ten decibels, which is twice as loud to the ear. A plot formally assigned to a traffic zone is legally allowed to be louder, and no window undoes that: windows only reduce what arrives inside.

From this follows a simple rule for choosing a location, which we discussed in the comparison Bar or Budva and in the piece on where it is better to live in Montenegro: a quiet apartment on a noisy street costs more than the same apartment on a quiet one — and the difference does not end up with you, it ends up in the façade construction.

Back to the wording of Article 5. The 30 dBA night limit applies with the windows of the room closed. Those four words change the entire logic of a design.

The window is the weakest point of the façade for sound, and it works as insulation only when shut. An open window, whatever its class, cancels the difference between a cheap and an expensive profile. So if meeting the rule requires the windows to be closed, the building has to be able to breathe without windows — otherwise the resident chooses between silence and fresh air.

This is exactly where acoustics and ventilation stop being separate subjects. We untangled that knot at length in the piece on ventilation, damp and noise in a seaside apartment: a sealed window without organised air supply predictably leads to rising humidity and condensation, and from there to mould. A supply-and-extract ventilation system is not a luxury here and not "smart home" — it is the condition under which the Article 5 rule is achievable in real life at all, rather than only on paper with the windows shut and the door to the hallway open.

A pleasant side effect: the air in the bedroom stays right all night. Why that matters more than it seems we wrote in the column on why you wake up tired.

A practical map — questions hang on it well.

1. Through the wall from the neighbour. Airborne sound, quantity R'w. Solved by mass and multi-layer construction: a heavy party wall, or a framed structure with two independent linings and cavity insulation. The main enemy is anything that passes straight through: a socket sitting in the same opening opposite the neighbour's undoes the entire wall.

2. Through the slab from above. Impact sound, quantity L'n,w. Solvable only during construction: a floating screed on an impact sound insulation layer that does not touch the walls at the perimeter. If the screed meets the wall anywhere, sound goes around and the whole floating floor stops working. This is the most common and the least repairable mistake.

3. Around, via adjoining elements. That same flanking transmission the prime in the rule stands for. Fixed by separation joints and decoupling at the junctions — that is, by design.

4. Through the façade from the street. The quantity is façade insulation, calculated to MEST EN 12354-3. It is determined above all by the window: its class, the quality of installation, the tightness of the joint. By the sea the window also has to carry corrosion-resistant hardware, which we wrote about in why metal by the sea rusts so fast.

5. From building services. Lift, pump, heat pump, fan, risers. Article 10 requires measures at the documentation stage. In practice what helps is vibration isolation of equipment, flexible connections on pipework, and moving noisy plant out from under habitable rooms.

There is no sixth path — if it is loud, it is because of one of these five. And four of the five are settled before the building exists.

Note how much of this depends on the quality of the load-bearing structures and junctions rather than on the finishes. The same principle holds in seismic performance: what determines how a building behaves sits in the structure and is invisible once construction is complete — we took that apart in the piece on earthquakes and building in Montenegro. Acoustics and seismic resistance are two properties you cannot buy afterwards, and both are decided at the same stage: in the design.

The list is short and the questions are verifiable. An evasive answer to any of them is itself information.

Is there a noise protection report, and may we see it? Under Article 7 it is a mandatory part of the technical documentation. Either it exists — or there is no design in the proper sense.

What R'w and L'n,w values are assumed between apartments and between floors? The answer has to contain two numbers and a note that they refer to the finished element in the building, not to the material's data sheet.

How is the floor built up: is there a floating screed and a perimeter edge strip? Impact sound is decided here and nowhere else. If there is no answer, there is most likely no solution either.

Where are the pump room, the lift shaft and the outdoor units, and what is below and beside them? Article 6 explicitly forbids a very noisy plant room adjoining an apartment.

How is the apartment ventilated with the windows closed? If the answer is "open a window", the Article 5 rule is met in that apartment only in theory.

A sixth item can be added — the question that separates a conscientious developer from the rest: are control measurements planned after completion? There is no obligation today, which makes a yes all the more valuable.

And what you can do yourself, if the building already stands and you are viewing a finished apartment. Come back a second time — on a weekday evening between nine and eleven, when the building is occupied and alive. Stand in silence for five minutes with the windows closed, and separately for five minutes with them open: the difference between the two is the work of the façade. Step out to the stairwell and ask someone to close the apartment door normally. Go up a floor and listen for whether footsteps are audible below.

About sound-level apps on a phone, honestly: they give an order of magnitude, not a measurement. A phone microphone is not calibrated, has no A-weighting in the form the rule requires, and at the quiet end of the scale — precisely around 30 dBA — it runs into its own self-noise. A reading of "34 dBA" on a phone proves neither compliance nor breach. For comparing two apartments in one evening with the same device such an app is usable; citing it in a conversation with a developer is not.

An honest division, with no promises.

Fixable. The window — replaceable, though not cheaply, and usually with the clearest effect against street noise. The entrance door — replaceable. Sockets facing the neighbour's — relocatable. Soft coverings, rugs, heavy curtains, shelves full of books along the party wall — they reduce reflections in the room and help a little, but they do not replace the wall. A noisy indoor unit or extractor hood — swappable for a quieter model.

Practically unfixable. Impact sound from above: fixing it requires a floating screed at the neighbour's, not at yours. Flanking transmission through the structure: load-bearing junctions cannot be separated in a finished building. Adjacency to a machine room: it does not move. A thin party wall: an internal lining costs floor area along the entire wall and delivers only part of the effect, because the detours remain.

There is a financial dimension to this division too. Noise is one of the few defects that feeds straight into yield: an apartment where the neighbours are audible rents less well and collects lower guest ratings, and ratings accumulate over years. If you regard the apartment as a source of rental income, acoustics stops being a question of personal comfort and becomes a line in the economics of the asset. The same holds from the other side of the counter: people renting long term almost always put quiet in their first three requirements.

A special case is the apartment that stands empty most of the year. Here noise works in reverse: you are not there, the neighbours are, and complaints accumulate against your name. How looking after such an apartment is organised and who checks on it in your absence we described in the apartment while you are away.

A simple rule: everything inside your apartment can be repaired for money; everything in the structure of the building or at the neighbour's cannot. That is why the questions in the previous section are asked before the deal. How decisions in a building are taken after move-in — through the owners' assembly and the manager — we described in who manages the building in Montenegro; agreeing with a neighbour to rebuild his floor is possible in theory and almost never in practice.

In the project's technical description, sound protection appears as two items: enhanced sound insulation between apartments and impact sound protection. The specific design values are in the project documentation; we deliberately do not publish a figure here until we can cite a document — by the same rule under which we declined to substitute Croatian values for Montenegrin ones.

What can be said in substance, because it follows from the configuration of the project itself:

24 apartments instead of the maximum the plot would allow. The building occupies 700 m² — 35% of a 2,000 m² site, with the remaining 1,300 m² given to the courtyard, garden and pool. Fewer apartments per floor means fewer shared walls, fewer people on the stairs and less load on the common structures. That does not replace an acoustic calculation, but it changes the starting conditions of the problem.

Supply-and-extract ventilation with heat recovery. Exactly what the "closed windows" section was about: the apartment is ventilated without opening the façade to noise.

Water-based underfloor heating on a heat pump. There are no radiators, no fan coils and no indoor split units in the habitable rooms — and therefore no permanent source of background noise in the room. Incidentally, that removes part of the question about temperature control and the electricity bill, which we covered in the piece on energy efficiency of an apartment.

Underground parking and a closed plot. Cars do not stand and start under the windows; entry is through an automatic gate.

A walkable roof instead of a plant floor. A garden, a yoga area and a summer cinema on the roof mean the top floor does not adjoin a machine room but a planted terrace. The Article 6 requirement that a very noisy plant room must not adjoin an apartment is met here by the layout rather than by silencers.

Prices and the mix of apartments are in the review of property prices in Montenegro, and the tax side of the transaction in the piece on tax when buying property.

The project's design and permit documents are published on the project page — including details of the investor and the main contractor. We hold to a simple principle: documents are shown before the purchase, not after. The best way to test a building for noise is to come and spend an entirely ordinary week in Montenegro, not a tourist one: how to arrange that we described in the piece on the holiday as a trial run for living.

What noise limit applies inside an apartment in Montenegro? Article 5 of Rulebook 060/18: the equivalent level LAeq in the habitable rooms of an apartment must not exceed 30 dBA at night and 40 dBA during the day, with the windows closed. The rule covers both indoor and outdoor sources.

Does the developer have to measure noise in the finished building? Not today. Article 12 on measurement is suspended by Article 14 until the day Montenegro accedes to the EU. Only the calculation at the design stage and the noise protection report as part of the technical documentation are mandatory.

Which matters more — R'w or L'n,w? It depends on what wakes you. R'w stands for voices and television behind the wall, L'n,w for footsteps from above. The second is complained about more often; only the first can be improved after buying, and only in part.

Do good windows help against neighbours? No. Windows work against street noise. Sound from a neighbour arrives through the wall and the slab and bypasses the façade.

Does an internal acoustic lining save the situation? Partly. It adds mass and decoupling, but it does not remove the detours through the slab and the junctions, and it costs several centimetres of room along the whole wall. As a substitute for a properly designed junction it does not work.

How much louder is 40 dBA than 30 dBA? About twice as loud in subjective terms. The decibel scale is logarithmic: every 10 dB means a doubling of perceived loudness, not an increase of a third.

Does noise affect resale price and letting? Yes, and letting most visibly: quiet ends up in the reviews, and reviews drive occupancy. On resale a noisy apartment is harder to show — the buyer arrives at exactly the hour when the building is living normally.

What can be done if the neighbours are audible in an apartment already bought? First identify the path — airborne or impact. Against airborne sound the window, the door, relocating sockets and a lining all help. Against impact sound from above, almost nothing helps inside your own apartment: the solution is in the neighbour's floor.

Ventilation, damp and noise in a seaside apartment — ventilation, humidity and sound as a single engineering problem.

Energy efficiency of an apartment in Montenegro — what the bill is made of and what affects it.

How to buy property in Montenegro: the full guide — taxes, procedure, notary and residence.

How to check a property in Montenegro — which documents to see before the deal.

15 mistakes when buying property in Montenegro — what most often turns out too late.

Why silence became the scarcest commodity — a short column on what buyers are really paying for.

Microclimate matters more than distance to the sea — why the address decides less than it seems.

Life in Montenegro, honestly — without the gloss, with the everyday detail.

Architecture beyond fashion — why solutions that do not age are usually also the most practical.