Air conditioning is becoming increasingly relevant to UK homeowners as warmer summers, larger areas of glazing, loft conversions and highly insulated homes create greater problems with overheating.

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Modern air conditioning can do considerably more than simply cool a room. Many fixed systems operate as air-to-air heat pumps, allowing the same equipment to provide efficient heating during winter and cooling during summer.

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The right air conditioning system will depend on the property, the rooms being treated, electricity demand, available locations for indoor and outdoor units and how the system fits into the wider energy strategy for the home.

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At APN Green Homes, we consider air conditioning alongside solar panels, battery storage, insulation, glazing, ventilation and heating rather than treating it as a completely separate installation.

How Does Air Conditioning Work?

 

An air conditioning unit removes heat from inside the property and transfers it outside.

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Most modern fixed residential systems use refrigerant circulating between an indoor unit and an external condenser.

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During cooling operation, heat is collected from the room and discharged outside.

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Many systems can reverse this process during colder weather, extracting heat from the outside air and bringing it into the property.

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This means the same equipment can potentially provide both air conditioning and efficient electric heating.

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Air Conditioning Units for Homes

 

There are several different types of air conditioning unit available for residential properties.

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The most appropriate system will depend on the size and layout of the home, the rooms requiring cooling and whether heating is also required.

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Common options include:

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• wall-mounted air conditioning units;

• mini split air conditioning;

• multi-split systems;

• ducted air conditioning;

• ceiling-mounted units;

• floor-mounted units; and

• portable air conditioners.

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Fixed systems normally provide a more permanent and efficient solution than portable equipment.

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Mini Split Air Conditioning

 

A mini split AC system typically consists of one indoor unit connected to one outdoor unit.

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This can be an effective solution for cooling or heating a particular room or area.

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Mini split systems are commonly used in:

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• bedrooms;

• home offices;

• extensions;

• loft conversions;

• open-plan kitchens;

• garden rooms; and

• living spaces prone to overheating.

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Where several rooms require air conditioning, a multi-split arrangement may allow several indoor units to connect to one external condenser.

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Multi-Split Air Conditioning

 

A multi-split system can provide heating and cooling to several rooms while reducing the number of external units required.

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Individual indoor units allow separate rooms to be controlled independently.

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This can be useful in larger properties where different bedrooms, living spaces or working areas have different temperature requirements.

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The design needs to consider pipe routes, electrical requirements, external-unit capacity and where indoor units can be positioned without adversely affecting the appearance of the rooms.

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Ducted Air Conditioning

 

Ducted air conditioning can provide a more discreet appearance because conditioned air is distributed through concealed ducts and grilles.

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The main equipment may be located within a loft, ceiling void or purpose-designed service space.

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Ducted systems can work particularly well during:

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• major renovations;

• new extensions;

• loft conversions;

• whole-house refurbishments; and

• projects where ceilings and services are already being altered.

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They generally require more design and installation work than individual wall-mounted units, so they are easier to incorporate before building work is completed.

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Portable Air Conditioners

 

Portable air conditioners provide a relatively simple way of cooling individual rooms without permanently installed equipment.

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They can be useful for occasional cooling, but they are generally different from a properly designed fixed air conditioning system.

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Portable units typically require warm air to be discharged through a window or external opening and may be noisier and less efficient than fixed split systems.

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For homeowners experiencing regular overheating, a permanent installation may provide a more practical long-term solution.

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Air Conditioning and Heating

 

Many homeowners do not realise that modern air conditioning systems can also provide heating.

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A reversible air conditioning unit works as an air-to-air heat pump.

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Rather than using direct electric resistance heating, the system transfers heat from outside the property into the room.

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This can make air conditioning particularly useful in rooms that need both winter heating and summer cooling.

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Examples include:

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• extensions;

• garden offices;

• loft rooms;

• conservatories;

• open-plan living spaces; and

• bedrooms affected by summer overheating.

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Air Conditioning for Loft Conversions

 

Loft conversions can be particularly vulnerable to overheating.

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They are positioned immediately beneath the roof and may include large areas of glazing or rooflights.

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Even with good insulation, solar gain can cause upper-floor rooms to become uncomfortable during hot weather.

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Air conditioning can provide controlled cooling and may also offer useful supplementary heating during winter.

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Where a loft conversion is being designed, it is worth considering air conditioning early so that pipework, electrical supplies and equipment locations can be incorporated into the building work.

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Air Conditioning for Extensions

 

Modern extensions frequently include large sliding doors, bifold doors and roof glazing.

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These features can create bright, attractive spaces but may also increase summer solar gain.

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Good design should first consider passive measures such as shading, appropriate glazing and ventilation.

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Where overheating is still likely to be a problem, air conditioning can provide controlled cooling.

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Planning the system during the extension design stage can make installation considerably easier.

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Air Conditioning and Solar Panels

 

Air conditioning can work particularly well alongside solar panels.

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The greatest demand for cooling often occurs on bright, sunny days when solar panels are also generating strongly.

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This creates an opportunity to use some of the electricity generated by the property to operate the air conditioning system.

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A home with solar panels may therefore be able to reduce the amount of grid electricity required for daytime cooling.

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The relationship between solar generation and cooling demand is one of the reasons air conditioning can fit naturally into a wider green home energy strategy.

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Air Conditioning and Battery Storage

 

Battery storage can provide additional flexibility.

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Surplus solar electricity generated during the day can potentially be stored and used later when cooling is still required.

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A home energy system may therefore combine:

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Solar panels generating electricity.

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Battery storage retaining surplus power.

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Air conditioning providing heating and cooling.

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Smart controls managing when electricity is generated, stored and consumed.

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The appropriate arrangement will depend on the individual property and household energy use.

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How Much Electricity Does Air Conditioning Use?

 

Electricity consumption depends on the size, efficiency and use of the system.

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Important factors include:

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• size of the room;

• insulation;

• glazing;

• solar gain;

• desired temperature;

• outdoor temperature;

• equipment efficiency;

• operating hours; and

• whether the system is heating or cooling.

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Oversized equipment is not automatically better.

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A properly selected air conditioning unit should be matched to the heating and cooling requirements of the space.

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Choosing the Right Size Air Conditioning Unit

 

Air conditioning systems should be sized according to the cooling load of the room.

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Factors influencing the required capacity may include:

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• floor area;

• ceiling height;

• orientation;

• window area;

• roof glazing;

• insulation;

• number of occupants;

• electrical equipment;

• solar gain; and

• intended use of the room.

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A professional installer can carry out the detailed calculations required to select appropriate equipment.

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Air Conditioning Cost

 

The cost of home air conditioning will vary according to the type and size of system.

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Factors affecting the overall price can include:

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• number of rooms;

• number of indoor units;

• number and size of external units;

• equipment manufacturer;

• pipe routes;

• electrical work;

• access;

• condensate drainage;

• scaffolding;

• controls; and

• complexity of the installation.

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A single mini split installation can be considerably simpler than a whole-house multi-room or ducted system.

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Homeowners should compare the quality, efficiency, warranty and design of the proposed system as well as the headline price.

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Air Conditioning Installation

 

A fixed air conditioning installation normally requires both indoor and outdoor equipment.

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The installer will need to consider:

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• position of indoor units;

• external condenser location;

• refrigerant pipe routes;

• electrical supply;

• condensate drainage;

• access for maintenance;

• noise;

• appearance; and

• future servicing.

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Careful planning can significantly improve both the appearance and performance of the finished installation.

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Where Should the Outdoor Air Conditioning Unit Go?

 

The outdoor unit needs sufficient airflow and access for maintenance.

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Possible locations may include:

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• rear elevations;

• side passages;

• gardens;

• flat roofs;

• balconies;

• courtyards; and

• suitable outbuilding areas.

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The position should also consider neighbouring properties and nearby windows.

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Placing the unit simply in the closest available location is not always the best solution.

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Air Conditioning Noise

 

Modern air conditioning systems can operate relatively quietly, but both indoor and outdoor units produce some noise.

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External condenser noise should be considered particularly carefully where units are close to:

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• neighbouring houses;

• bedroom windows;

• boundaries;

• enclosed courtyards; and

• narrow side passages.

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Good equipment selection and positioning can reduce the risk of disturbance.

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Does Air Conditioning Need Planning Permission?

 

Many small domestic air conditioning installations may be relatively straightforward, but planning considerations can arise depending on the property, equipment and location.

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Particular care may be required for:

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• listed buildings;

• conservation areas;

• flats and maisonettes;

• prominent elevations;

• external units close to boundaries;

• roof-mounted equipment; and

• installations involving several external units.

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Where there is uncertainty, the planning position should be established before equipment is ordered.

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Air Conditioning in Conservation Areas and Listed Buildings

 

External air conditioning units can affect the appearance of a property and may require more careful positioning in sensitive locations.

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For listed buildings and properties within conservation areas, it may be necessary to consider less visible locations and minimise alterations to historic fabric.

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Pipe routes, external equipment and internal units should all be considered as part of the overall design.

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Where planning drawings or applications are required, these should be dealt with before installation.

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Air Conditioning in Flats

 

Installing air conditioning in a flat can be more complicated than installing it in a house.

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Potential issues can include:

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• leasehold restrictions;

• freeholder consent;

• external alterations;

• suitable condenser locations;

• planning permission;

• noise;

• access; and

• pipe routes through communal areas.

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These issues should be investigated before selecting equipment or committing to installation.

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Air Conditioning and Ventilation

 

Air conditioning and ventilation perform different functions.

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Air conditioning primarily controls temperature.

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Ventilation replaces stale indoor air with fresh air.

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A well-designed home may require both.

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This becomes particularly important as properties become more insulated and airtight.

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Systems such as MVHR can provide controlled ventilation while air conditioning deals with heating and cooling.

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Air Conditioning and Insulation

 

Improving insulation can reduce the amount of energy required to heat and cool a property.

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Good insulation helps retain heat during winter and can also reduce unwanted heat transfer during summer.

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However, insulation alone does not necessarily prevent overheating caused by large glazed areas or strong solar gain.

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A whole-home assessment can consider insulation, glazing, shading, ventilation and cooling together.

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Air Conditioning Service and Maintenance

 

Fixed air conditioning systems require periodic maintenance to keep them operating effectively.

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An air conditioning service may include inspection and cleaning of filters, indoor units, outdoor equipment, drainage systems and other components.

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Regular maintenance can help maintain efficiency, reduce the likelihood of breakdowns and identify problems before they become more serious.

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The service requirements will depend on the equipment and how heavily the system is used.

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Air Conditioner Repair

 

Like any mechanical equipment, air conditioning units may occasionally require repair.

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Problems can include loss of cooling performance, unusual noise, leaks, drainage issues or electrical faults.

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Repairs should be undertaken by appropriately qualified air conditioning professionals.

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When considering a new system, it is worth asking about warranties, servicing arrangements and the availability of future technical support.

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Air Conditioning During a Renovation

 

A renovation can be one of the best times to plan air conditioning.

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Walls, ceilings and electrical systems may already be accessible, making it easier to conceal pipework and provide suitable power supplies.

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The design can also be coordinated with:

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• insulation;

• glazing;

• ventilation;

• heating;

• solar panels;

• battery storage;

• electrical upgrades; and

• smart-home controls.

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This can produce a cleaner installation and reduce the need for disruptive work later.

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Is Home Air Conditioning Worth It?

 

That depends on the property and the problem you are trying to solve.

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Air conditioning may be particularly worthwhile where a home has:

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• persistent summer overheating;

• loft bedrooms;

• large areas of glazing;

• south-facing living spaces;

• home offices containing computer equipment;

• poorly ventilated rooms;

• extensions with significant solar gain; or

• a requirement for efficient heating and cooling from the same equipment.

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The decision should consider comfort, installation cost, electricity consumption and how the system will interact with other home improvements.

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Air Conditioning as Part of a Green Home Plan

 

Cooling is becoming an increasingly important part of home energy planning.

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A greener home is not simply one that stays warm efficiently during winter.

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It should also remain comfortable during increasingly warm summer conditions.

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Air conditioning can therefore form part of a wider strategy involving insulation, shading, glazing, ventilation, solar generation and smart energy management.

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The objective is to create a property that performs well throughout the year.

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Independent Air Conditioning Advice

 

An air conditioning installer will naturally concentrate on supplying and installing cooling equipment.

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APN Green Homes takes a broader approach.

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A Green Home Survey can consider whether air conditioning appears appropriate, which parts of the property are affected by overheating and whether alternative or complementary improvements such as insulation, glazing, shading, ventilation or solar panels should also be considered.

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The aim is to determine what the home actually needs before investing in equipment.

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Start With the Property

 

The best air conditioning solution begins with understanding why the property is overheating, which rooms require treatment and how heating and cooling fit into the wider energy demands of the home.

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NEXT STEPS

Every home is different, so the right next step depends on your property, your budget and what you want to achieve. APN Green Homes can help you turn the information you have just read into a practical plan for your own home. Whether you are considering one improvement or looking at a complete whole-home energy upgrade, we can help you understand what is suitable, what should be prioritised and where your money is likely to make the greatest difference.

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Choose one of the options below to get the ball rolling:

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BOOK A GREEN HOME SURVEY
Get a detailed assessment of your home with practical, property-specific recommendations and a clear plan for the improvements worth considering.

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BOOK A PHONE CONSULTATION
Talk through your property, ideas and priorities with us and get some initial direction on the best way forward.

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EMAIL US
Send us details of your property, photographs or any questions and we can advise you on the most appropriate next step.

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GIVE US A CALL
Prefer to speak to someone? Give us a call and tell us what you are hoping to achieve.

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Your greener, more efficient home starts with understanding the right improvements for your property — and putting them in the right order.