Are you allowed to install one?

Modifying common parts or the building's external appearance requires authorisation from the co-ownership (copropriete / mede-eigendom), framed by the Civil Code co-ownership rules and the building's statutes. Approval by the general assembly (with the majority set in the rules) is generally needed when the outdoor unit affects the facade, a balcony or the roof, even where the unit serves only your apartment. Check the co-ownership statutes (acte de base / reglement) and the required majority before ordering.

Under the EU F-gas Regulation (EU) 2024/573, a person who installs, services, repairs or decommissions stationary AC or heat-pump equipment containing fluorinated refrigerant must hold the European refrigeration competence certificate (category I, II, III or IV) and be recognised by the competent regional authority (in Flanders, erkenning als koeltechnicus, registered before starting work; equivalent recognition in Wallonia and Brussels). The certificate covers A2L refrigerants such as R32. Hermetically sealed factory-charged portable monobloc and window units need no on-site refrigerant work and are exempt. From 29 March 2026 the EU moves to a new personal certificate structure valid across the EU.

A portable monobloc placed inside the home with the hose led through an open window, with no drilling and no facade change, is normal use of the rental and needs no permission. A fixed split, an air-to-air heat pump, an outdoor unit on the balcony, drilling the wall or any visible change to the facade is a structural alteration: the tenant must obtain the landlord's written consent first. If the building is a copropriete, the landlord must also clear it with the syndic and the assemblee generale, and a declaration prealable applies if the facade changes. Installing a visible fixed unit without authorisation can be ordered removed by a judge, with a daily penalty.

Fixing an outdoor unit to a common element (facade, roof, balcony guardrail) affects the common parts and the building's external appearance, so it requires authorisation voted by the assemblee generale des coproprietaires at the absolute majority of article 25 of the Law of 10 July 1965 (a majority of the votes of ALL co-owners, present, represented or not). If absolute majority is not reached but the project gets at least one third of all votes, a second immediate vote can pass at the simple majority of article 24. The reglement de copropriete can restrict or ban visible units, and meetings are usually annual, so plan months ahead and obtain this before the town-hall declaration.

Where the property is in a protected sector (site patrimonial remarquable, abords de monuments historiques, a classified or registered monument, or a nature reserve), a declaration prealable is required even for an outdoor unit that would otherwise be exempt (including a non-visible heat pump or the building of a support platform), and the file is reviewed by the Architecte des Batiments de France (ABF). The ABF can require concealment or refuse a visible outdoor unit.

Under the French Code de l'environnement (articles R543-99 and R543-106, transposing the EU F-gas regime), the owner must have any charging, commissioning, leak check, servicing or decommissioning of equipment containing fluorinated refrigerant performed by a company that holds an attestation de capacite (issued by an approved body such as AFNOR, Bureau Veritas, Cemafroid, Dekra, SGS or Socotec) and by technicians who hold the individual attestation d'aptitude. Operating without a valid attestation can expose the company to heavy penalties (up to 75,000 EUR fine). New competency and capacity rules set by two Arretes of 21 November 2025 become mandatory on 1 January 2027 (existing attestations remain valid during the 2026 transition, with refresher training due by 12 March 2029).

Before installing a portable, window or split unit, read your lease and obtain the landlord's written consent. Window and split installs involve drilling, brackets or wall penetrations that can damage the property, and split systems also require a certified installer. Some places (e.g. Oregon) protect a tenant's right to a portable unit, and disability accommodations may apply, but rules vary, verify locally.

A fixed split system involves drilling the exterior wall and mounting a compressor on the facade, both structural modifications (bauliche Veranderung), so written landlord consent is required before installation. Air conditioning is NOT a privileged measure under Section 554 BGB (unlike balcony solar/Steckersolar since 2024), so the landlord has wide discretion and may refuse for objective reasons (appearance, Denkmalschutz, facade thermal-insulation/statics, neighbour noise). The landlord may also make consent conditional on removal and full restoration of the wall opening at the tenant's cost when moving out.

Stationary AC equipment with fluorinated greenhouse gases (F-gases such as R-32 or R-410A) may only be installed, serviced, maintained, repaired, or decommissioned by certified personnel and certified companies, because connecting refrigerant lines and opening the circuit are certification-required activities. This follows the EU F-gas Regulation (EU) 2024/573 with its certification implementing regulation (EU) 2024/2215, applied in Germany via the Chemikalien-Klimaschutzverordnung (ChemKlimaschutzV); a Kategorie I certificate covers full work on AC circuits. A retailer may sell a split unit to a private person only against written proof that a certified company will do the installation. Units charged with R-290 (propane) are non-fluorinated and fall outside F-gas certification, and pre-charged plug-in portable monobloc units need no certified installer.

Mounting a split outdoor unit on the common facade of a Wohnungseigentumergemeinschaft (WEG) is a bauliche Veranderung that requires a resolution (Beschluss) of the owners' meeting before installation. Since the 2020 WEG reform (Section 20 WEG) it can be approved by simple majority. The Federal Court of Justice (BGH) confirmed on 23 May 2025 (V ZR 128/24) that a WEG may permit split air-conditioning units by majority resolution, that abstract noise objections alone do not block such a resolution, and that the permit need not include every technical document up front. A single owner who is genuinely disturbed later can still demand abatement under Section 1004 BGB and Section 14 WEG. Installed without any resolution, a co-owner can demand removal.

Articles 1102 and 1122 of the Civil Code let an owner use common parts but forbid works that damage them or harm the building's stability, safety or decoro architettonico. You should notify the amministratore before the work. Assembly authorisation is not always required if the install respects those articles, but it becomes mandatory where the condominio regolamento requires it or the work is invasive; a regolamento or assembly resolution fixing where and how units may sit (for example only inside balconies, not on the main facade) is binding even on private parts visible on the facade. The Cassazione assesses each case (size, position, visual impact, building rules), for example ordering removal of units encroaching on others' airspace (Cass. 11337/2026).

Placing an outdoor unit usually requires permission from the vergadering van eigenaars (VvE), since the facade, roof and other common parts are shared even when the unit serves only your apartment. The VvE can set conditions (liability, maintenance, casing colour, cable routing) and a municipal permit does not replace its consent. Check your splitsingsreglement and the required majority before ordering equipment.

Under the EU F-gas Regulation (EU) 2024/573 (as implemented in the Netherlands), installing, servicing or decommissioning stationary AC equipment that contains fluorinated refrigerant must be done by a person holding the relevant F-gas (refrigeration) competence certificate working for a certified company (in the Netherlands the company certificate scheme is BRL 100 / 200). The certification covers A2L (mildly flammable) refrigerants such as R32. Hermetically sealed, factory-charged portable monobloc and window units need no on-site refrigerant work and are exempt. Note: from 29 March 2026 the EU is moving to a new personal F-gas certificate structure valid across the EU.

Under Real Decreto 115/2017 (handling and marketing of fluorinated gases, implementing EU F-gas rules), any technician who installs, services or recovers refrigerant from AC equipment must hold the certificado de manipulador de gases fluorados, and the work must be done by an empresa habilitada. Installers of fixed thermal installations also need the RITE professional qualification (habilitacion / carnet RITE). At purchase, the buyer and the authorised installer sign a declaration confirming a certified company did the work. Installing a split without these certifications is unlawful and can bring large fines. Plug-in portable monobloc units are factory-sealed and do not need on-site refrigerant work.

Under the Ley de Propiedad Horizontal (Ley 49/1960), Article 7 lets an owner modify their own elements only if it does not impair the building's security, structure or its exterior configuration or appearance, and the owner must notify the community (president/administrador) beforehand. Installing an outdoor unit on common parts such as the facade affects a common element, so it generally needs a favourable vote: a 3/5 qualified majority of owners and quotas under Article 17 where it alters the building's exterior; community statutes can restrict or ban visible units. Under recent (2026) practice the community can require you to remove or relocate a unit installed without notice or that harms others. Verify your community's rules.

Under the GB Fluorinated Greenhouse Gases Regulations, the individual engineer must hold a personal F-gas qualification (Category I covers all install, service, recover and decommission activities; commonly delivered as City & Guilds 2079), and the company (including sole traders) must hold an F-gas company certificate from an approved body such as REFCOM, renewed every 3 years. This is required to install, service, maintain, repair or decommission any system holding fluorinated refrigerant. Working on F-gas equipment without the correct qualifications and company certificate is against the law and can attract a civil penalty. DIY refrigerant work is not lawful. (Hermetically sealed, factory-charged portable monobloc and window units do not need this.)

Under Section 608 of the Clean Air Act (40 CFR Part 82, Subpart F), anyone who connects gauges, adds or removes refrigerant, or services or disposes of refrigerant-containing equipment must hold EPA 608 certification (Type I for small/sealed appliances, Type II for high-pressure split systems, or Universal). Hire a 608-certified HVAC contractor for any split installation.

Arizona has no statewide building department, so permitting is municipal, but cities like Phoenix (and Mesa, Scottsdale, Tucson and others) adopt the International Mechanical Code and require a mechanical permit to install or replace AC equipment, including a same-spot, same-type condenser or furnace change-out, followed by an inspection. A like-for-like change-out usually does not need a new load calculation if capacity stays within about 10 percent of the original. A licensed contractor normally pulls the permit. Verify the rule with your city's planning and development department.

In Flanders, since the new Vrijstellingenbesluit took effect on 1 March 2026, the above-ground parts of a heat pump or air conditioner in the garden, on a facade (now including the front facade) or on a flat roof are exempt from an urban-planning permit if placed at least 2 metres from the property boundary (perceelsgrens) or against an existing dividing wall, provided the home is authorised and heritage and local rules are respected (protected heritage is excluded). Separately, an environmental melding (VLAREM class 3) applies to cooling/heat-pump installations from 5 kW, and a permit (class 2) only from 200 kW. In Wallonia an outdoor unit is exempt from a permis d'urbanisme under the CoDT only if it is on the ground, a flat roof or fixed to a facade, kept at least 3 metres from shared boundaries, not visible from the access roadway and outside a high flood-risk zone, otherwise a permis d'urbanisme is required, and a cooling-only climatiseur often needs one. In Brussels a prior notification (or permit) is generally needed where the unit is visible from the public way. Always verify with your commune.

Pull a permit and comply with Title 24, Part 6. Permit applications filed on or after 1 January 2026 fall under the 2025 Energy Code cycle (earlier applications stay on the 2022 cycle). Most central AC and heat pump changeouts need HERS verification by a certified rater, with the CF-1R completed at permit, the CF-2R by the installing contractor, and the CF-3R after field verification. HERS measures include refrigerant charge (now verified in every climate zone for heat pumps), airflow, and duct leakage (must stay under 5 percent of system airflow for single-family homes when ducts are altered or cooling is added). Equipment must also meet your climate zone's minimum SEER2/EER2. Repairs like a capacitor or thermostat generally do not need a permit.

The Florida Building Code (structural provisions using ASCE 7 wind loads) requires outdoor AC equipment and its mounts (pad, stand, wall bracket, tie-downs) to be anchored to resist the local design wind speed, which runs from roughly 140 mph inland up to about 170 to 180 mph in coastal zones. In the High-Velocity Hurricane Zone (Miami-Dade and Broward counties) the equipment attachment must be backed by a Florida Product Approval or a Miami-Dade Notice of Acceptance with tie-down details, or by signed and sealed engineer documents. A condenser cannot simply sit loose on a plastic pad. Confirm the wind speed and tie-down detail for your address.

Under the Florida Building Code (Mechanical) and Florida Statutes Chapter 489, a permit is required to install, replace, or relocate AC equipment (a condenser or air handler change-out), and the completed work is inspected by the local building department. The installer must be a licensed mechanical/HVAC contractor; replacements typically use an equipment change-out application. Like-for-like minor repairs (for example a capacitor or thermostat) generally do not need a permit. Requirements and fees vary by city/county, verify with your local building department.

An outdoor unit that changes the external appearance of the building requires a declaration prealable de travaux filed with your mairie (the 'declaration prealable constructions et travaux non soumis a permis de construire', Cerfa form), with a site plan and a description. If the installation does not change the external appearance it is generally exempt, except in a protected sector (where a declaration is required even for a non-visible unit or a support platform). There is no power or capacity threshold; always check your commune's local urban-planning rules (PLU).

Submit an architectural-change request and get written approval before installing an outdoor condenser, a through-wall unit, or a visible window unit. Provide the unit's dimensions, noise rating, and proposed location relative to property lines. Unapproved exterior equipment can be fined or ordered removed. Varies, verify with your governing documents.

If the building is listed (UK) or in a designated historic district / landmark (US), apply for the relevant consent (Listed Building Consent or a Certificate of Appropriateness) before installing. Authorities favour discreet rear/side placement and screening, and may refuse facade-mounted or roadside units. Portable units that need no fixings are the lowest-risk option. Varies, verify locally.

For a building under Denkmalschutz, every externally visible change affecting the appearance or historic fabric is subject to approval (Erlaubnis) by the Denkmalschutzbehorde, governed by the heritage-protection law of the relevant Bundesland. Visible outdoor units on the street facade are usually refused; courtyard, rear-facade, or no-outdoor-unit (monobloc/hose) solutions are typically required. Engage the authority early, as approval is decided case by case.

In an area under vincolo paesaggistico (Codice dei beni culturali e del paesaggio, D.Lgs 42/2004, autorizzazione paesaggistica under Article 146), an outdoor unit visible from public space requires landscape authorisation from the Comune and the Soprintendenza. The Consiglio di Stato (ruling 7426/2021) confirmed an AC unit visible from outside cannot be treated as edilizia libera exempt from landscape authorisation; installing without it triggers a mandatory restoration/demolition order. A simplified authorisation (autorizzazione paesaggistica semplificata, DPR 31/2017) may apply for minor works.

Under the Massachusetts State Building Code (780 CMR), installing or replacing a system such as a ductless mini-split or central AC requires a permit and inspection from the local building department (minor like-for-like component repairs are usually exempt). The refrigerant side of the work must be performed by a technician holding the Massachusetts Refrigeration / Air Conditioning license (Division of Professional Licensure, Board of Examiners of Sheet Metal Workers) plus EPA Section 608 certification, and ductwork requires a sheet metal license. Local interpretation varies, confirm with your building department.

Under Massachusetts General Laws Chapter 40C, exterior changes visible from a public way in a designated local historic district require a certificate of appropriateness, non-applicability, or hardship from the local historic district commission before work begins. Whether an outdoor condenser or window unit is exempt depends on the specific town or city bylaw: some districts exempt air conditioners, others review them, and commissions favor discreet rear or side placement and screening. Apply to your local historic district commission and confirm whether AC is exempt under your district's bylaw.

For a rijksmonument (or a municipal/provincial monument) or a property in a rijksbeschermd stadsgezicht, an omgevingsvergunning is required, including a monumentenactiviteit where the building itself is protected. On a national monument every externally visible change, however small, needs permission, and units on the front or side, or where the rear faces public space, are the most likely to be refused. Apply through the Omgevingsloket; decisions can take up to 8 weeks plus an objection period.

Under the Omgevingswet and Besluit bouwwerken leefomgeving (Bbl, in force since 1 January 2024), a wall or roof unit is typically permit-free if it protrudes no more than 0.5 m, and a ground unit if it is no higher than 1 m with a footprint of no more than 2 m2 and needs no digging. An omgevingsvergunning is required when those limits are exceeded, when the unit goes on the front facade or a facade facing public space, when structural changes are needed, or when the property is in a rijksbeschermd stadsgezicht. The national 40 dB(A) noise limit at the property boundary applies even when the placement is permit-free. Verify the local rules with your gemeente.

Depending on the unit's power and the works involved you typically file a declaracion responsable or a licencia de obra menor with your ayuntamiento (often around 50 to 150 EUR for a private home). Municipal ordinances add siting rules: in Madrid a facade unit may not protrude more than 30 cm from the facade plane and must not raise the temperature of nearby premises by more than 3 C measured 1.10 m from the affected window, and a licence is mandatory. Installing on a facade without the required licence can bring fines (roughly 600 to 3,000 EUR) and an order to remove the unit. Verify your ayuntamiento's ordinance.

For a building protected as a Bien de Interes Cultural (BIC), a catalogued building, or one in a protected area / special protection plan, a building licence (licencia de obras) and heritage authorisation are required for any external intervention. Visible units on the main facade are generally prohibited; permission is usually only for interior courtyards, rooftops, or secondary facades not visible from public space, with concealment using materials compatible with the original architecture. Works affecting common elements of a BIC building can need unanimity of the community. Fines for unauthorised installs on protected buildings are higher. Verify with the local ayuntamiento and the autonomous-community heritage authority.

Anyone who installs, services, or replaces AC and refrigeration systems must hold (or work under) a Texas Department of Licensing and Regulation (TDLR) Air Conditioning and Refrigeration (ACR) contractor license under Occupations Code Chapter 1302. The local authority (city or county) requires a mechanical/building permit and an inspection for the work. Under Occupations Code Section 1302.304 a municipality may not charge a TDLR-licensed ACR contractor a separate registration fee, but it may still charge ordinary building-permit fees. Verify the permit process with your local building department.

Permitted development (Class G) does not apply within the curtilage of a listed building, so installing an external unit there needs planning permission and Listed Building Consent for the unit and any fixings. In a conservation area or World Heritage Site the unit must not be installed on a wall or roof that fronts a highway; many installations there fall outside permitted development and need full planning permission. Apply to your local planning authority before installing, and favour a discreet rear or side location.

Pull a mechanical permit from your local building department for the AC installation, plus an electrical permit if a new circuit or disconnect is added (and a gas permit for gas-fired equipment). An inspector verifies the work against local code. Requirements and fees vary significantly by city and county. Verify locally before work begins.

Apply to your local Historic Preservation Commission for a Certificate of Appropriateness (COA) for exterior alterations, including condensers and through-wall or facade-mounted units. Commissions favour low-visibility rear or side placement, concealed line-set covers, and screening. Some districts exempt easily removable window units; others do not. Varies, verify locally.

Check your CC&Rs and architectural/design guidelines, then submit an architectural modification request to the Architectural Review Committee before installing. Include the unit's spec sheet (dimensions and noise) and a site plan showing placement and distance to property lines. Reviews commonly take 30 to 60 days; unapproved installs can be fined or ordered removed. Varies, verify with your association.

Under ARS 33-1816 an association may not prohibit the installation or use of a solar energy device; it may adopt only reasonable placement rules that do not prevent installation, impair the device's function, or adversely affect its cost or efficiency. ARS 44-1761 defines a solar energy device as a system designed primarily to provide heating, cooling, electrical power, mechanical power, or daylighting from solar energy, so a solar-powered or solar-thermal cooling system falls under this protection. A standard electric AC condenser is not a solar device and stays subject to normal HOA architectural review, so submit a request and approval for a conventional unit. Courts award attorney fees to a homeowner who prevails against a board that violates this section.

Noise rules are regional. In Flanders the guideline limits in VLAREM II / the Code van goede praktijk for a residential zone are about 40 dB(A) by day and 30 dB(A) at night at the affected dwelling's boundary (units serving a home are also expected to stay close to the day 45 / night 40 dB(A) range used for built-in installations). In Wallonia the neighbourhood-noise rules set a strict night limit (around 35 dB(A)) at the boundary. In Brussels the Arrete du 21 novembre 2002 (bruit de voisinage) and the classified-installation thresholds apply by zone and period (for a typical residential Zone 2, about 45 dB(A) day, 39 dB(A) evening, 33 dB(A) night, with an emergence limit over ambient noise). Site the unit away from neighbours, use quiet mode and verify the applicable regional and municipal code.

Under Article 5 of Regulation (EU) 2024/573, operators of stationary air-conditioning equipment containing 5 tonnes of CO2-equivalent or more of fluorinated greenhouse gases must arrange periodic leak checks by certified personnel: at least every 12 months under 50 tonnes CO2-eq (extendable to 24 months with a leak-detection system), more often above that, and keep records for each system. Most single residential splits are below 5 tonnes CO2-eq and are exempt, but larger multi-split and VRF installations can exceed it. Hermetically sealed units below the charge threshold are also exempt.

Under Regulation (EU) 2024/573 the installation, commissioning, servicing and decommissioning of stationary AC equipment containing fluorinated greenhouse gases must be carried out by personnel holding an F-gas certificate (the EU 'Category I' qualification issued by an accredited body in a Member State) and, for companies, a company certificate. Member States are extending these certification programmes to cover alternative and mildly flammable (A2L) refrigerants such as R32 and R454B, and refresher training becomes mandatory at least every seven years. DIY refrigerant connection is not lawful.

Under article R1336-7 of the Code de la sante publique (in force, neighbourhood-noise regime), the noise 'emergence' (the increase over the residual ambient noise, measured at the neighbour's) must not exceed 5 dB(A) between 07h and 22h and 3 dB(A) between 22h and 07h. A duration-based correction is added (from +6 dB(A) for one minute or less down to 0 dB(A) for more than 8 hours of the particular noise). Exceeding the limit is an abnormal neighbourhood disturbance and can bring a fine.

Under Decret n 2020-912 of 28 July 2020 and articles R224-44 to R224-44-5 of the Code de l'environnement, thermodynamic systems (air conditioners and reversible heat pumps) with rated power between 4 kW and 70 kW must undergo maintenance every two years by a qualified professional, who issues a maintenance certificate (attestation d'entretien) within fifteen days. Systems whose total installed power exceeds 70 kW are instead subject to a periodic energy inspection at least every five years. Equipment containing fluorinated refrigerant must be serviced by an operator holding the attestation de capacite. This is an upkeep and energy-performance obligation on the owner, not a barrier to buying.

Check the local noise limit measured at the nearest neighbour's boundary or window (commonly around 37 dB in the UK MCS 020a assessment and roughly 45 to 55 dB(A) in many US ordinances, lower at night). Choose a quiet unit, site it away from neighbouring windows, add anti-vibration mounts, and screen it. Verify the exact local figure before installing.

Central and split systems typically require a dedicated higher-voltage circuit with a correctly sized breaker and an outdoor disconnect. In the US, NEC 2023 Article 440 sizes branch-circuit conductors at 125 percent of the rated-load or branch-circuit selection current (440.32), requires a disconnecting means within sight from and readily accessible from the equipment (440.14), and as of the 2023 edition requires that disconnect to meet the 110.26(A) working-space clearances. Window units over about 7 amps should also have a dedicated circuit. Have a licensed electrician confirm your panel has spare capacity before buying; portable monoblocs run on a normal outlet but can still overload a shared circuit. Codes vary by country, verify locally.

Under the Gebaudeenergiegesetz (GEG), air conditioning systems (or combined air conditioning and ventilation systems) with a rated cooling output of more than 12 kW are subject to energy-efficiency requirements (Sections 65 to 70 GEG, e.g. specific fan power, demand control, heat recovery, cold-line insulation) and to a recurring energetische Inspektion by a qualified inspector, repeated at fixed intervals (around every 10 years). The duty applies in both non-residential and residential buildings. Typical single-room residential splits stay below 12 kW and are not affected; the rule mainly reaches large multi-split or central comfort-cooling systems. A successor law (Gebaude-Modernisierungs-Gesetz) is planned for late 2026, so verify the current paragraph numbering.

Domestic split air conditioners are frequently verfahrensfrei (no formal Bauantrag) under the relevant Landesbauordnung, but building law is a state competence so thresholds and boundary (Abstandsflache) rules vary by Bundesland. A unit can become relevant to the required boundary distance (often around 2.5 to 3 m to the property line) if it counts as a building part, and a permit or heritage approval is still required for listed buildings, larger or roof-mounted installations, or changes to the street facade. Always check your state's Landesbauordnung and confirm the boundary distance before installing.

Under the TA Larm immission guide values (Section 6.1), noise from the outdoor unit must not exceed, in a general residential area (allgemeines Wohngebiet), 55 dB(A) by day (06:00 to 22:00) and 40 dB(A) at night (22:00 to 06:00); in a purely residential area (reines Wohngebiet) 50 dB(A) day and 35 dB(A) night; in mixed/village/core areas (Misch-, Dorf-, Kerngebiet) 60 dB(A) day and 45 dB(A) night. The measurement point is NOT the property boundary: per TA Larm Anhang A.1.3 it is taken 0.5 m outside the centre of the open window of the neighbour's most affected habitable room. Position the unit, keep distance, and use night/quiet mode so the night limit is met (a single short noise event must also not exceed the limit by more than 30 dB(A) at night).

Under DPCM 14 November 1997 (limit values implementing the framework noise law 447/1995), the differential immission limit measured inside a neighbour's dwelling must not exceed 5 dB(A) during the day (06:00 to 22:00) and 3 dB(A) at night (22:00 to 06:00), being the difference between ambient noise with the unit running and residual noise. The differential criterion does not apply when measured ambient noise is very low (below 50 dB(A) day or 40 dB(A) night with windows open, 35/25 dB(A) windows closed). Comuni also set absolute limits by acoustic zone. Site the unit away from windows, use silent mode and anti-vibration mounts; civil nuisance under art. 844 Civil Code can also apply.

Massachusetts offers three codes: the base code, the Stretch Code (225 CMR 22 residential / 225 CMR 23 commercial, 2025 amendments to IECC 2021), and the municipal opt-in Specialized Code. The Stretch Code has been adopted by over 270 of the state's 351 cities and towns and is mandatory in those communities, and about 60 have adopted the Specialized opt-in code. It pushes higher equipment efficiency and electrification: for example a compliant air source heat pump (which includes mini-splits) is generally expected to meet around 16 SEER / 10 HSPF, above the federal floor. Check which code your municipality enforces before choosing equipment.

National building rules (Besluit bouwwerken leefomgeving, Bbl, in force since 1 January 2024, continuing the rule that has applied to units placed on or after 1 April 2021) cap the noise of an outdoor installation for heat or cold generation (heat pump or air conditioner) at 40 dB(A) in the evening and night (19:00 to 07:00) and 45 dB(A) by day (07:00 to 19:00). It is assessed at the perceelsgrens (property boundary) of an adjacent plot, or, for units serving an apartment on the same plot, at the window or door of a neighbour's room. Articles 4.107 lid 2 and 4.108 lid 3 Bbl; the level is calculated per the Omgevingsregeling. A unit with a night or silent mode usually meets this.

Co-op and condo boards (and landlords) commonly regulate or ban window units, drilling into the facade, and require specific brackets, so get written board approval before installing. Buildings six stories and taller fall under Local Law 11 (the Facade Inspection Safety Program, FISP), under which exterior-mounted window units and their brackets can be inspected as part of facade safety; the program does not itself mandate a particular bracket, but it is why boards in tall buildings often require a properly engineered exterior bracket. Confirm your building's specific house rules first.

No permit is needed for a window unit at or below 3 tons / 36,000 BTU per hour (larger units do need a permit). The NYC Department of Buildings requires the unit to be supported from underneath or firmly fastened from inside with angles; supporting metal brackets and interior angles must be structurally fastened to the building envelope and strong enough for the unit's size and weight. Any object used to level or position the unit must have its own independent source of fastening (no loose wood blocks, bricks, or books), and the unit must stay in place when the window is opened.

Installation must comply with the municipal ordenanza de ruido, set within the national framework of Ley 37/2003 del Ruido and Real Decreto 1367/2007 (acoustic zoning and quality objectives). Residential-area outdoor limits are commonly around 55 dB(A) day and 45 dB(A) night, with stricter values measured inside the affected dwelling (and some city ordinances cap residential outdoor units near 45 dB(A) day / 30 dB(A) night). Exact limits and measurement points are set locally, so verify your municipality's ordinance. Use silent mode, anti-vibration mounts and good siting to comply.

Fixed thermal installations, including air conditioning, must comply with the Reglamento de Instalaciones Termicas en los Edificios (RITE), approved by Real Decreto 1027/2007 and updated (last by RD 178/2021 transposing the EU energy-performance directive). RITE sets minimum energy efficiency for cooling/heating generation and fluid-transport equipment, and design, installation, inspection and periodic-maintenance obligations. Larger installations require a registered project/technical report and a maintenance contract. This sits on top of the EU energy label; informational for buyers choosing efficient equipment.

Under Texas Property Code Chapter 202, an HOA generally may regulate the appearance and placement of an outdoor condenser through its architectural review (where on the lot, screening, color), so get written approval first. But Section 202.010 bars an HOA from prohibiting a solar energy device (which can power or run cooling): it may only impose reasonable rules on location and appearance that do not raise cost or reduce efficiency more than 10 percent. Section 202.019 similarly protects standby generators. A standard electric AC condenser is not itself a protected solar device, so it remains subject to normal HOA architectural rules. Check your CC&Rs.

Under Class G, outside a conservation area the unit must not be installed on any part of a wall above the level of the ground-floor storey where that wall fronts a highway. On land within a conservation area or World Heritage Site the unit must not be installed on a wall or roof which fronts a highway, and must not be nearer to a highway bounding the curtilage than the nearest part of the building. The most discreet location (rear or side, low to the ground, screened) is the safest way to stay within permitted development.

Wales: from 1 June 2026 (the Town and Country Planning (Permitted Development) (Wales) Order, WSI 2026/79) the previous 3 metre from boundary rule was removed, the volume limit rose to 1.5 cubic metres, up to two units are allowed on a detached house, and installations must comply with MCS 020 a). Scotland: under the Scottish GPDO an outdoor unit must be on a wall or roof not fronting a road, sit no more than 1 metre above ground level, generally keep about 1 metre from the boundary, be limited to one heat pump per property, and meet the noise standard (a phase 3 consultation that could relax this closed in October 2025). Northern Ireland: since 4 July 2023 (SI amending the Planning (GPDO) (NI) 2015) units are permitted development only if at least 1 metre from a neighbouring property boundary and compliant with the prescribed noise standard. Air-to-air cooling-only equipment is not necessarily covered the same way as a reversible heat pump. Verify with your local planning authority.

The installation must pass the MCS 020 a) (Air Source Heat Pump Sound Calculation) assessment: the assessed sound must not exceed 37 dB LAeq (5 minutes) measured 1 metre external to the centre of a door or window of a habitable room at the nearest neighbouring property. This tightened the previous 42 dB(A) threshold when MCS 020 a) replaced the older MCS 007 standard on 29 May 2025. From 28 May 2026 the previous equivalent route closes and MCS 020 is the only certification scheme accepted for permitted development. A noisier or poorly sited unit loses permitted development status and needs planning permission.

Install under Class G (GPDO Part 14, the Town and Country Planning (General Permitted Development) (England) Order 2015 as amended by SI 2025/560 from 29 May 2025). The outdoor compressor (including housing) must not exceed 1.5 cubic metres on a house or 0.6 cubic metres on a block of flats. A non-detached house or block of flats may have one unit; a detached house may have up to two (the 29 May 2025 relaxation, which also removed the old 1 metre from boundary limit). It must not be on a pitched roof, must sit at least 1 metre from the external edge of a flat roof, and must comply with the MCS Planning Standards (now MCS 020 a) noise assessment). The heat pump must not be used solely for cooling, so a pure cooling air conditioner falls outside Class G and needs planning permission.

R-32 and R-454B are A2L (mildly flammable) refrigerants. Equipment using them is built and must be installed to the updated UL 60335-2-40 safety standard and the A2L provisions adopted into the model mechanical and building codes, including refrigerant charge limits per room area and, on some products, factory leak detection and mitigation. Only equipment rated for the specific refrigerant may be installed, mixing refrigerants or retrofitting an R-410A system with an A2L is not allowed, and a 608-certified technician is still required to handle the refrigerant. The EPA venting prohibition (no knowing release of refrigerant) applies to these substitutes.

Under NEC Article 440, branch-circuit conductors for the AC compressor must have an ampacity of at least 125 percent of the motor-compressor rated-load current or the branch-circuit selection current, whichever is greater (440.32), with overcurrent protection sized to the equipment nameplate. A disconnecting means must be located within sight from and readily accessible to the unit (440.14), and in the 2023 NEC that disconnect must also meet the 110.26(A) working-space clearances (it cannot block access to or obscure the nameplate). Window units over about 7 amps should be on their own circuit. Have a licensed electrician confirm the panel has spare capacity and that the install meets the code edition your jurisdiction has adopted.

Check your lease and building rules: co-ops, condos and landlords often regulate or ban window units, drilling into facades, or require specific brackets. In New York City, window air conditioners must be installed so they cannot tilt, slip or fall, and the unit must be securely supported, not propped on loose shims. Buildings over six stories are covered by Local Law 11 (the Facade Inspection Safety Program, FISP), under which the Department of Buildings inspects facades every five years and can flag an unbraced or unsafe window unit as an unsafe condition; a properly fastened exterior support bracket or mounting rail is the standard way to comply. Verify your building's policy and the current DOB guidance.

Check your municipal noise ordinance: residential limits commonly fall around 50 to 55 dB(A) at the property line, lower at night (often 45 to 55 dB(A)). For example, Los Angeles County's standard for AC condensers is 50 dB(A) measured 3 feet from the property line. Site and screen the unit to stay under the limit. Varies, verify locally.

Under ARS 33-1324 a landlord must supply running air conditioning or cooling where such units are installed and offered when required by seasonal weather, and ARS 33-1364 treats cooling as an essential service: if the landlord deliberately or negligently fails to supply it, the tenant may give written notice and then either procure reasonable substitute cooling and deduct the actual reasonable cost from rent, or recover damages and seek other remedies. This duty applies regardless of unit type once cooling is provided. Local rules in Phoenix and Tucson set indoor temperature ceilings for habitable rooms, verify your city's standard.

Under the California Air Resources Board (CARB) prohibitions on use (17 CCR 95374, Table 3), new air conditioning and VRF equipment, residential and commercial, must use a refrigerant with a GWP below 750, with high-GWP equipment (including R-410A at GWP about 2,088) prohibited as of 1 January 2025. This aligns California with the new A2L refrigerants R-32 and R-454B. Separately, under SB 1206 the sale of virgin (non-reclaimed) HFCs is phased down by GWP: 2,200 or higher banned from 1 January 2025, 1,500 or higher from 1 January 2030 (which reaches R-410A used for servicing), and 750 or higher from 1 January 2033. Reclaimed refrigerant is exempt and may still be used to service existing systems. An EPA 608-certified technician is still required for any refrigerant work.

California falls in DOE's Southwest region, which adds an EER2 (hot-day) floor that the North does not. For split-system central AC under 65,000 Btu/h, the minimums are: under 45,000 Btu/h, 14.3 SEER2 plus EER2 11.7 (or EER2 9.8 if certified SEER2 is 15.2 or higher); 45,000 Btu/h and above, 13.8 SEER2 plus EER2 11.2 (or 9.8 at high SEER2). Split-system heat pumps must meet 14.3 SEER2 and 7.5 HSPF2. In the Southwest the central-AC regional standard is enforced at installation, so equipment below the minimum cannot lawfully be installed. These minimums apply in addition to Title 24, Part 6 climate-zone requirements and HERS verification.

Regulation (EU) 2024/573 (in force since 11 March 2024) replaced the 2014 F-gas Regulation and tightens the HFC phase-down against the 2011 to 2013 production baseline: producers receive rights equivalent to about 60 percent of their 2011 to 2013 average from 2025, declining to about 15 percent by 2036, with HFCs phased out in the EU by 2050. R410A (GWP about 2088) is being replaced by lower-GWP refrigerants, principally R32 (GWP 675) and R454B (GWP about 465), both used in new split systems.

Hermetically sealed, factory-charged monobloc and window units do not require on-site refrigerant connection, so no F-gas installer certificate is needed to set them up. F-gas servicing rules still apply if a sealed unit ever has to be opened or scrapped, which is a job for a certified technician.

Under the Ecodesign and Energy Labelling framework (Delegated Regulation (EU) 626/2011, as corrected by Regulation (EU) 2023/2048), air conditioners with rated cooling capacity of 12 kW or less must display an energy label showing the SEER (Seasonal Energy Efficiency Ratio) for cooling and, for reversible units, the SCOP (Seasonal Coefficient of Performance) for heating, plus annual kWh consumption. The label drives the minimum-efficiency (ecodesign) rules and is informational for buyers comparing running costs.

The EU is rescaling energy labels to a single A (most efficient) to G (least efficient) scale across product groups, but as of June 2026 air conditioners have NOT yet been rescaled. AC and comfort-fan labels still use the older scale under Delegated Regulation (EU) 626/2011: reversible and double-duct cooling-dominant units run A+++ down to D, and split/window units use an A to G scale with a '+' added at the top. A rescaled plain A to G label for air conditioners is expected later this decade once the Commission updates the delegated act; no binding application date is in force yet.

Under Annex IV of Regulation (EU) 2024/573: from 1 January 2025 single split systems with under 3 kg charge using a refrigerant with GWP of 750 or more are prohibited. From 1 January 2027 split air-to-water systems up to 12 kW with GWP of 150 or more are banned. From 1 January 2029 split air-to-air systems up to 12 kW with GWP of 150 or more are banned, and split systems above 12 kW with GWP of 750 or more. From 1 January 2035 all split systems up to 12 kW that use F-gases are banned. Self-contained (monobloc) and multi-split units have their own earlier dates (GWP 150 or more banned from 1 January 2027, all F-gases from 1 January 2032). Dates and thresholds vary by system size and type.

Route condensate (and any defrost/portable-unit water) to a proper drain or soakaway, not over a boundary, walkway or onto a unit below. In many US cities and buildings, allowing AC water to drip onto a public way or neighbouring property is a code or nuisance violation; window and portable units especially need a planned drainage path. Verify your local building/condo rules.

Using a mobile/monobloc unit whose exhaust hose is only directed through an open or tilted window is generally permission-free, because there is no structural change (bauliche Veranderung) to the building. The tenant simply pays for the electricity used. Any permanent modification (a wall duct, a fixed window panel screwed in place, fixed brackets) would again need landlord consent. A simple textile/zip window seal is allowed and recommended.

Installing an energy-efficient (heat-pump) air conditioner can qualify for the bonus ristrutturazione income-tax deduction (50 percent for a primary residence, 36 percent otherwise in 2026, spread over 10 years, within the 96,000 EUR cap, art. 16-bis TUIR), or the Ecobonus when it fully replaces an existing system. Purchase and installation of high-efficiency equipment benefit from reduced 10 percent VAT instead of 22 percent. For heat pumps the Conto Termico 3.0 grant can cover a substantial share of the cost. Energy-efficiency works generally require a telematic notification to ENEA within 90 days of completion. This is a regulatory/fiscal framework, informational for buyers; verify current rates with the Agenzia delle Entrate.

Installing or replacing an air-to-air heat pump or air conditioner with nominal useful thermal power below 12 kW on an unconstrained property is edilizia libera (free building activity) under Article 6, comma 1, lett. a-bis of DPR 380/2001, so no permit, SCIA or even CILA is needed. The work must be carried out by a qualified firm that issues a conformity declaration. A CILA (or, where the look of the building changes, a SCIA) is needed for larger systems (cautiously advised from 12 kW upward, required above 40 kW) and where the local regolamento edilizio imposes it. In landscape or heritage zones, autorizzazione paesaggistica is required regardless (see the heritage rule).

Local Law 23 of 2026 (Int 994-A) requires residential landlords to provide adequate cooling on a tenant's request, delivered by central cooling or by individual window or similar units. During the cooling season (June 15 through September 15) sleeping rooms must be kept at or below 78 degrees Fahrenheit when the outdoor temperature exceeds 82 degrees. The law phases in over about four years: tenants can begin formally requesting cooling, and full enforcement begins June 1, 2030. It is a tenant right rather than an installation restriction, so renters in NYC should know cooling can be requested from the landlord.

Class G condition G.3(d) requires that the air source heat pump be removed as soon as reasonably practicable when it is no longer needed. The same set of conditions also requires the unit to be sited, so far as practicable, to minimise its effect on the external appearance of the building and its effect on the amenity of the area. Keep the removal duty in mind for rented or short-term installations.

Under DOE standards (10 CFR 430.32(c)), residential central AC and heat pumps made on or after 1 January 2023 are rated with SEER2/EER2/HSPF2. For split-system central AC under 65,000 Btu/h the regional minimums are: North 13.4 SEER2; Southeast 14.3 SEER2 under 45,000 Btu/h and 13.8 SEER2 at 45,000 Btu/h and above; Southwest (AZ, CA, NV, NM) 14.3 SEER2 plus EER2 11.7 under 45,000 Btu/h (EER2 floor 9.8 if SEER2 is 15.2 or higher) and 13.8 SEER2 plus EER2 11.2 at 45,000 Btu/h and above. Split-system heat pumps have a national minimum of 14.3 SEER2 and 7.5 HSPF2. In the North the standard is enforced at manufacture; in the South and Southwest the regional AC standard is enforced at the point of installation, so an installer cannot fit a sub-minimum unit.

Under the EPA's AIM Act Technology Transitions Rule (40 CFR Part 84, Subpart B), residential and light-commercial AC and heat pump systems manufactured or imported on or after 1 January 2025 must use a refrigerant with a GWP at or below 700. This moves new equipment off R-410A (GWP about 2,088) onto A2L refrigerants, mainly R-32 (GWP about 675) and R-454B (GWP about 466). A 2026 EPA final rule (effective 27 July 2026) removed the hard 1 January 2026 installation cutoff: pre-2025 R-410A field-assembled units and components may continue to be installed until existing supplies run out. For self-contained products such as window units and portable room ACs, the final date of sale is three years after the manufacture compliance date, no later than 1 January 2028. Some states are stricter (for example New York keeps a 1 January 2026 ban on installing R-410A systems), so verify your state.