Is It Cheaper To Have An Extension Or Conservatory?

If you’re planning to extend your home, you have a couple of options available to you: adding a conservatory or adding an extension.

Whilst both have their merits, each has its disadvantages too, and more than likely which one you choose will come down to personal taste. However, there a few considerations to each option to think about, so let’s delve in and give you more information to make an informed decision.


Many homeowners looking to expand their property – be that for extra living space, sunrooms, home offices or other reasons – the question of how best to get that space is a popular one. So, which is the best option – a conservatory or an extension?

Loft conversions are common, so too, cellar conversions. However, both of these can end up being costly options – costs such as tanking a cellar often being more significant than the cost of simply building a brand new addition to the house. Finding the right duplex build is an important decision. Check out our range of the best home design constructions at Home Builders. 

And that is perhaps why conservatories and extensions seem to be the most popular projects – but which one of these is the best option for you?

What Is The Difference Between A Conservatory And An Extension?

Both a conservatory and an extension will afford your home a unique new look, but what are the differences between the two?


  • Conservatories are typically attached to the back of a house.
  • Conservatories are mainly glass-built, designed originally to encourage the growth of indoor plants.
  • A conservatory will give your home a light, a bright new room that makes an ideal extra living space that can be used all year round, depending on the type of glass used and the materials’ thermal and insulating properties.
  • A conservatory can be constructed to match your home’s structure and brickwork to ensure it’s a seamless addition to your property. We can even include windows that match the existing ones on your home.
  • Conservatories are available in all shapes and sizes, so whatever your needs, there is something available to suit your taste and budget.


  • An extension can be built anywhere on your home where you need extra space and where you have land to accommodate it.
  • An extension is constructed usually from the same materials as your home to blend in with the original structure. Made with an insulated roof and walls, an extension can be used for any purpose you see fit: a kitchen, bathroom, bedroom, living room, garage. There are no restrictions (within reason) on what you can use your new space for.
  • Extensions can be used all year round, just like any other room in your house.
  • An extension will typically require planning permission and most definitely will require building regulation approval.

Extension Or Conservatory Melbourne

What Will Space Be Used For?

The first thing to consider before anything else is why you want the extra room – and what will it mainly be used for.

If you want an extra bedroom, a conservatory is not going to be suitable. But it could be perfect if you want a new office, dining space or additional living room.

Thinking about the purpose of a space will help focus the mind and weigh up whether you need a single-storey addition or something more sizeable with two storeys.

A modern conservatory offers homeowners many different ways to use a space for almost any purpose – such as a living room, dining room, playroom, library, music room, office or kitchen.

An extension is even more flexible when it comes to usage and can also be utilised as a bedroom. With creating extra bedroom space now recognised by property developers as the best way to add the most value to a home’s asking price, this factor might influence your decision, especially if you intend to sell in future.

Where Will The New Room Be Located?

The location where you want the new room to be built can also influence whether to choose a conservatory or extension.

If your conservatory is going to be east-facing, it will enjoy the sun in the morning. If it is west facing, you’ll enjoy the sun towards the end of the day, whereas a north-facing room will get a bit of both. 

If your conservatory aspect is south facing, the space will be warm and inviting in summer but could potentially become uncomfortable during the hottest times of the day.

Thinking about these factors is essential so that you can plan for the right level of ventilation, blinds and heating to allow you to enjoy a welcoming conservatory space all year round.

Thanks to its insulated walls and roof, a brick-built extension is unlikely to be affected by seasonal temperature fluctuations. Hence, the direction it faces is not as important when it comes to its design.

Pros And Cons Of A Conservatory

A conservatory is an excellent way to create just a little extra space, whether you want a dining room, play area or just a bright space to relax in. If you want a way to spend time in the garden without being exposed to the elements of the great British summer, then a conservatory allows you to bring the garden indoors. Images of greenhouses for a blog post by London based architects, Extension Architecture, examining the advantages and disadvantages of conservatories and home extensions. 

There are many options when it comes to conservatory design, such as the roof shape, materials and types of doors. They are so versatile and can be designed to suit any style of home. Unlike having an extension added to your home, a conservatory does not usually need planning permission and having it built will be much less disruptive and messy than an extension. Conservatories are often cheaper than an extension, too, although they don’t add the same value an extension does, and they aren’t everyone’s cup of tea. At Home Builders, we have the best dual occupancy selection to make your house a dream come true.

Keeping a conservatory at a suitable temperature can be a struggle, often being too cold in winter and too hot in the summer. Heating a conservatory effectively can be expensive and ongoing during the colder months. On the flip side, depending on your conservatory faces, they can become very hot during the summer. There is the option to have unique windows put in, which help regulate the temperature, but they are expensive and inefficient.   

If your garden is overlooked, which many houses in London boroughs will be, a conservatory offers no privacy. And not many people would be happy having their neighbours gawp at them whilst they eat their dinner. A conservatory is perfect if you don’t need to use the room all the time and want a smallish room. Otherwise, you might want to consider choosing to have an extension built.  

Pros And Cons Of An Extension

If you’re desperate for a larger kitchen with a dining area, or an office and guest room, you should probably consider having an extension built. Building an extension has many benefits. You have a lot more options when it comes to design, size, shape and location. Whether you want to extend to the side, rear, or go up into your loft space, an extension gives you much more choice. Once you have paid for the materials and work on a single storey extension, it is often not hugely more expensive to go the whole hog and have a double-storey extension built, so you could end up with a lovely new kitchen diner and a bedroom to boot!   

Images of extensions for a blog post by London based architects, Extension Architecture, examining the advantages and disadvantages of conservatories and home extensions. Being constructed from more robust materials than a conservatory, an extension will last longer and be useable all year round. New rooms created by an extension can be used for almost anything, whether you need extra bedrooms or a more oversized kitchen. 

Plus, an extension will add more value to your home than a conservatory. With many design options such as sliding or bifold doors, and all the glazing options available, it is still possible to get that feeling of bringing the outdoors in with an extension. It can’t be avoided that the cost of an extension is higher than that of a conservatory. But an extension is, arguable, better value for money, allowing you to create much more space than you can use all year round.     

It is worth noting that building an extension may require planning permission; it’s a good idea to make sure you have these in place before you start your extension to avoid issues further down the line. Plus, unlike the set cost of a conservatory, you could find yourself with extra costs if any problems arise or changes need to be made to the design. Having an extension built onto your home can be more invasive than having a conservatory added. You could potentially end up living on a building site with some of your home inaccessible for an extended period.  

Popular Home Extension Options

There are typically 3 ways to create more living space in your home.

  • Extend upwards.
  • Extend outwards.
  • Extend downwards.

Extending upwards

In most cases, extending upwards means a loft conversion. Converting the attic’s unused space is a tried & trusted method of making the most of your existing property to create extra living space.

Popular uses are as a study/home office, an extra bedroom or bathroom/shower.

Converting the attic space is not something to be undertaken lightly, simply because of all the extra weight loading created by converting the room to a habitable environment.

Whilst you may be able to do certain types of loft conversions without planning permission, you will certainly need to meet building regulations.

If you live in a semi or terraced house, you may need to inform the neighbours of your proposed project if it falls under the party walls act.

Experts should only undertake this work with a lot of direct experience in this type of project.

The most significant advantage is that you don’t need to use any exterior space, so if you have no outside area to extend, you can make use of the loft.

You can also keep it relatively simple if you like, just adding flooring and stud walls to create a study or bedroom.

Extending Outwards

Conservatory Vs ExtensionA traditional bricks & mortar extension at the side or rear of the property remains very popular for those who have space. A new kitchen or dining area is very often the reason for the extension.

Double height extensions can give excellent value for money, but you need a healthy budget.

The advantages of external extensions are that you can have them designed to your specifications, simple, ornate or ultra-modern. There are unlimited options. They are also proven to add monetary value to any property.

If you have one to convert, then a garage conversion could be a good option. As the main structure is already there, the construction work is avoided, and internal work is required. However, you need to follow some guidelines.

Extending Downwards

Converting an existing basement is unlikely to require planning permission and can be done simply as a garage conversion.

Creating a new basement (digging one out) is a whole different ballgame. Fraught with difficulty and the costliest per cubic metre of space, you have to consider this one in-depth and consult with highly experienced experts. At Home Builders, we offer a wide range of duplex build.

Popular Conservatory Options

Modern Conservatory Vs Extension DesignsAdding a conservatory to the side or rear of a property seems to have become the “National Pastime”. Conservatories are hugely popular as ways to add more room to the house.

The advantages are many:

  • They are readily available from a vast number of suppliers.
  • Lots of variation in size & designs.
  • Easy to install, in a matter of a week or 2, with little disruption.
  • They add resale value to the property and make it more desirable for buyers.
  • Cost-effective – you get a lot of living space for your money.
  • Most small to medium size conservatories can be built without planning permission.

The disadvantages are few and mainly centre around usability during hot or cold weather. However, if you take advantage of the latest glazing technology, then a modern conservatory can be used all year long.

In terms of design choice, there are a few significant styles and then many variations of those, for example:

  • Victorian conservatories – plus variations such as the P-shape or B-shape.
  • Lean-to conservatories – plus variations such as L-shape, T-shape.
  • Edwardian conservatories – plus variations such as T-shape.
  • Georgian conservatories – Plus variations such as L-shape, T-shape.

You can also choose the primary material from which to build, such as aluminium, timber or uPVC.

In terms of the need to get planning permission to build a conservatory, if you fall within the Permitted Development guidelines (link below), you can usually build without it.

The Same Difference?

The advances made to conservatory roofs mean that there is very little difference between the two for many purposes.

Extensions and conservatories can now be enjoyable spaces all year round, suitable for a whole range of uses. Both also blend in sympathetically to the rest of the property – no longer are conservatories a glass bolt-on. Instead, the roofs come in a range of styles and subtle colours, ensuring they closely match the rest of the house. Looking for dual occupancy? Look no further! Home Builders has you covered. 

And both even have the massive advantage of adding value to the property. Of course, it varies by postcode, type of house and other factors, but both can be appealing to would-be buyers in future. In many cases, conservatories with solid roofs more than pay for themselves. The money spent on them is less than the property’s increased value when it is later sold.

Which One Looks The Best?

There’s no better way to bring the outside into your home than by installing a conservatory.

Although a brick-built extension with its plasterboard walls and tiled roof offers a certain degree of solidity, conservatories typically look more impressive because they are made from a more significant glass proportion.

Perfect in warm weather or colder months, their glazed aspect helps to create a light and airy space that everyone can enjoy all year round.

If you want to bring the outside in during summer, throw open the doors to the garden and seamlessly merge the exterior space with the inside of your home – allowing you to relax and enjoy hours of evening sunshine. In colder months, you can still snuggle up and get cosy inside whilst admiring all the best elements of a traditional winter garden.

Unfortunately, a dull extension doesn’t always look as appealing as a conservatory.

If you decide to opt for a brick-built structure, make sure it’s an attractive design that can introduce lots of natural light like a conservatory; otherwise, it could feel dark and uninviting. 

Adding a stylish Skypod to a flat-roof extension is a subtle way to achieve a stunning focal point, but the use of lighting and furniture is an affordable alternative.

When choosing between a conservatory or extension, it is also essential to consider how specialised additions will impact future property sale. 

If you’ve always dreamt of having a hot tub or concealed bar in your new extension, these may not appeal to prospective buyers and may end up being worth less than they cost to install.

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