Garden Office Costs

This article will explain what you are paying for when you have a garden office built into your backyard.

We'll cover the average costs, supply costs, additional costs, tradesman costs, and any other information you need to know before getting a garden office built.

How Much Does It Cost to Build a Garden Office?

Garden offices are becoming increasingly popular, but how much does it cost to construct a garden office? If you want to learn more about the costs of building a garden office, keep reading.

While it would be perfect to have an accurate cost estimate for each type of garden office, this is not feasible. Instead, you'll have to add insulation yourself because most of them don't come with it. It's not a difficult task if you have the right tools.

On average, a purpose-built garden office costs between £9,000 and £10,000. These are the structures that come to mind when we think of a garden office.

A purpose-built office can be obtained in two ways: you can order buildings based on a predefined blueprint and have the components supplied and ready to assemble or hire an architect to design your building, particularly for your space, with a construction team sourcing the materials for you.

The latter will increase the cost of your garden office, but you will be able to tailor it to your exact needs.

A brick garden office will cost between £23,000 and £25,000. However, if you have the space and are willing to go through requesting planning permission, this could be a viable option.

Your role is to specify what you want and how you want it and ensure that your designer or construction crew can meet those requirements. The advantage of this is that it can be converted into a separate, self-contained dwelling.

As a result, depending on the overall quality of the construction and bespoke amenities, a small garden office pod can cost between £5,000 and £20,000, while a medium to a large garden office can cost between £12,000 and £20,000.

If you get a quote from a contractor, remember to factor in the cost of any foundations that will be required and the cost of plumbing and drainage for a shower or toilet, if one is included. A toilet will typically cost between £1,000 and £2,000, while a shower room can cost £3,000.

The cost of a garden room, on the other hand, varies greatly based on the materials used or the features included. For example, many brands offer construction and painting services, but these are usually extra.

Renowned experts estimate the average costs of establishing a high-quality garden room. For example, in London, the cost of a full and installed garden room ranges between £15,000 and £16,000, while in other areas such as the North, the cost ranges between £12,000 and £16,000, depending on the design and materials required.

Garden Office Prices

Supply Only Costs

Depending on where you buy it, laying the groundwork may be included in the overall cost of the garden room; however, in some cases, you may need to hire groundworkers and landscapers to prepare the plot ahead of time.

In most cases, garden offices do not require the same foundations as a house. The most common procedure is to prepare a concrete slab base. A small concrete slab base - around 2m by 2m - will cost around £1,500 - £1,800, depending on ground conditions and easy accessibility, with garden office prices increasing as the size grows.

Another common option is to use ground screws, dug into the dirt to the desired depth and then used as a base for the room's frame. These are particularly useful where the ground is not flat and has a lower long-term effect than a concrete foundation. A ground screw system can cost between £2,000 and £2,500, depending on the device's size being built.

Additional Costs

If you want a luxurious garden office, you must be ready for the cost of your garden office to rise. For example, if you want it painted and decorated, you will have to pay more for a tradesperson to come in and work.

The additional costs of garden office construction are listed below to understand what might be added to your garden room.

Floor Insulation

It is relatively simple to insulate a concrete floor during construction. Insulation is installed either above or below the concrete during the construction phase. To retrofit a concrete floor, insulation must be installed above it. An insulated garden office is much more comfortable and can be used throughout the year.

Polyisocyanurate, also known as the PIR board, is a popular rigid insulation board. It is typically supplied in 1.2 metres by 2.4-metre sheets that can be cut to size. Depending on thickness and rating, PIR insulation costs around £20 - £60 per sheet.

Glass mineral fibre can be used on concrete floors, and a roll can cover about six square metres for around £25 - £30 per roll, depending on thickness. Polystyrene sheets are simple to manage and install beneath or above concrete, providing excellent thermal resistance.

Floor insulation made of extruded and expanded polystyrene comes in 2.4 metres by 1.2-metre sheets and costs around £15 per square metre.

Suspended floors have a void underneath and are built on floor joists. These materials are excellent candidates for retrofitting floor insulation, and there are numerous options available, including glass mineral wool, sheep wool, PIR board, and loose-fill insulation.

Sheep wool floor insulation is a natural material treated to ensure its durability. It costs between £18 and £25 per square metre. Loose-fill insulation costs about £1.50 per kilogramme on average.

If you would like further information, please refer to our guide on the costs of installing floor insulation.

Doors and Windows

When choosing your garden room, the door and window you use will usually be an option, ranging from less costly uPVC frames to more pricey hardwoods. Timber garden offices tend to be the most aesthetically pleasing option. However, you may want to make your garden room's doors or windows a focal point, allowing you to take advantage of the outdoor space and natural light.

Wall-to-ceiling windows that take up the entire side of the room and bi-fold doors that open an entire side of the room and let the outside in are very popular. However, these can raise the overall cost by £2,000 to £3,000.

Painting

Painting a room is a simple task for any painter or decorator, and it is something that any DIY enthusiast can do. But how much does it cost to hire a professional? Of course, this is almost entirely determined by the size of the room.

A standard 4m by 3m room would take a couple of days to paint completely, including woodwork and coving.

Outside of London, most decorators charge around £150 to £200 per day, so your total labour cost would be around £300 to £400. Adding another £50 for the paint results in a total cost of £400.

If you would like further information, please refer to our guide on the costs of painting a bedroom.

Architect Costs

To complete a loft conversion, not all contractors will require architect plans. However, making plans is still a good idea. It means that everyone is aware of the desired outcomes. For £400, you can get a basic set of plans. You can expect to pay up to £1,500 for more detailed plans that outline the full scope of the work.

Given the project's cost, this is not a large sum, but it can significantly improve it. Another advantage of hiring an architect to create detailed plans is that you will be less likely to change your mind later, saving you money in the long run.

If you would like further information, please refer to our guide on the costs of hiring an architect.

Costs of Underfloor Heating

If you are adding an ensuite to your loft space, you should think about installing underfloor heating. Putting it in now will be less expensive than trying to fit it later. The size of the room will determine the price. The average cost is between £350 and £850.

If you would like further information, please refer to our guide on the costs of underfloor heating.

Labour Costs and Timescales

The expenses of tradespeople for building a garden office are discussed further below. This section will also go over the various cost factors that can influence and change a tradesman's price.

The average daily labour cost is expected to be between £170 and £190. This assumes that a group of workers will be on-site to construct an outbuilding.

However, depending on the type of labourers hired and other factors, labour costs can reach £1,000 per day. However, we will base our calculations on the daily average labour cost.

The labour cost would be between £275 and £325. The number of people working on the project, the length of the job, the ease of access, the condition of the workspace, and your location in the UK are all common factors that influence labour costs.

The number of people working on the project, the length of the job, the ease of access, the condition of the workspace, and your location in the UK are all common factors that influence labour costs.

Work on your office will begin as soon as the construction crew arrives. On-site construction teams are typically made up of two to four people. The number is frequently determined by the size and complexity of the structure.

Other team members, including electricians and plasterers, may appear during the construction phase if additional skills and experience are required.

It's important to note that if you choose plastering and our acoustic pack, the process could take a few weeks longer to enable the plastering to cure. But, overall, the construction time is short, and the planning time is not much longer. So, here are the various timeframes for constructing your garden office.

Building a small to medium-sized modular garden office design takes about two days. However, most garden office building projects take between 7 and 10 days to complete on-site.

Painting

If you're only painting a small bedroom, it should only take one day; however, you'll need to add another day if you need any wallpaper or paint eliminated. The job could take three to four days if you want the tradesman to remove and replace any furniture.

Electricity

A new plug socket installation can take up to two hours. If significant new wiring is needed, or if the room has still not been connected in the event of an extension, this time will be increased.

Flooring Replacement

Another important factor to consider when assembling a new floor is the time required, affecting the overall cost.

Doors and Windows

A limited or average-sized window can take over an hour to install with one expert installer. On the other hand, a large window can be installed in as little as two hours with two expert installers or as little as three to four hours just with one worker.

Cost Factors of Building a Garden Office

There are many types of cost factors for building a garden office, and we will go through the different cost factors that could affect the overall cost of your garden office.

Location

It's critical to understand that the garden room price will rise if a location is difficult to reach. Tradespeople may need to plan their work around your garden room and home. This necessitates more effort and time.

As a result, the lower the costs, the more easily accessible the location. In contrast, it will take more effort and time to access the land in less accessible locations. This will be reflected in a higher price and more time.

Size

When it comes to size, the larger the garden room, the more expensive it will be. This is only natural. The larger the room, the more materials and time are required to construct it. This means that the garden room will be more expensive.

There are additional costs to consider. For example, many people overlook the fact that constructing a larger garden room will necessitate the use of more screws, nails, and other materials. If your large garden room requires additional steel or aluminium, the price may rise.

Form

Next, the shape of your garden room will influence the cost of construction. Garden rooms with unusual shapes, for example, tend to be more expensive. Walls that are not joined at right angles raise the cost as well. Other features, including a walkway or pergola, can also raise a garden room price.

Costs of Planning

There will be an application fee of around £170 if you need to qualify for Planning Permission to construct your garden room. Normally, your supplier will include drawings in the project cost, and a small fee could be charged for the drawings and specifications. However, if Building Control approval is required, there may be additional fees to pay.

Delivery Fees

Several garden room companies are selling their structures on a national scale. When working with a company, not near you, you should read the fine print, as many will charge a delivery fee above a certain radius of their workshops.

This is usually 100 miles. Anything over that is usually charged by the mile, with prices as high as £6 per mile not uncommon.

Electricity Supply

When purchasing a garden room, the most common additional cost is hiring a local electrician to connect the electrics to the mains electricity and then test the circuit. This cost is determined by the distance between your garden room and the house, as an armoured cable must be buried underground.

Warranties Backed by Insurance

Most businesses provide warranties on their buildings for a set number of years. Some companies go a step further and offer insurance-backed warranties, meaning that if they go out of business, any work will still be covered.

What's Involved in Building a Garden Office?

A DIY garden office isn't for everyone, and there are some things you won't be able to do yourself, such as the electrics, but the structure itself can be accomplished relatively easily with a few select tools, some research, and some time. Self-build garden offices are quite a popular choice. If you're looking for a cheap garden office, the DIY route may be the best option.

Time is of the essence here, as you'll need to devote about a week in dry weather to finish the main structure. You'll also need another two weeks to complete the interior and visual style touches. I finished my office mostly around work. With this and the bad winter weather, it's taken a little more than two months.

Location Planning

Grab a piece of paper and a tape measure, and head outside to consider the best location for your new structure. Consider the following elements:

Do you have a suitable flat space to begin your construction, or will you need to do some groundwork or build an appropriate support frame? Is there anything that needs to be avoided or removed, such as trees, underground pipes, or electrical wiring? Which direction will the office entrance be facing? When and where do the sunrise and set?

Because you'll need access to all sides of the building, leaving a suitable gap between neighbouring limits is critical for construction and future maintenance. The bare minimum is 50cm.

Will you require a walkway to the front door? You may already have an appropriate route, but others may only have a lawn, which isn't ideal for dragging dirt and mud around, especially in the winter months.

Are you hiding behind a tree? This may not seem important, but my building is. During the autumn season, the office is always covered in fallen leaves from the trees, which must be removed. It's not the best job, and if not cleared, it can cause problems with the felt roofing.

Size. What size will your structure be? When designing your ideal space, keep material sizes in mind.

Electrics. How will you power your office? You'll need a certified electrician to insert your electrics, and the cost will rise the further you are from home. An armoured cable will be required to connect your home and office, which will be costly. It will have to be dug underground or installed along a fence, which can take a long.

Consider how you will build your office, including the roof, floor, and wall designs. There are numerous ways to accomplish this, so consider the following:

The Foundation and The Floor

Plinth supports are less expensive and provide relatively improved water drainage. This option, however, will create a void beneath your structure, allowing vermin to nest or cold air to circulate, reducing thermal efficiency.

Solid foundations will provide your office with the most stable and long-lasting support, but they will also be the most expensive. Concrete construction would provide a level and durable foundation on which to build.

The Partitions

Most walls will be structurally similar, but you must consider the type of insulation and cladding you prefer. An office without insulation will be extremely cold in the winter, so consider this carefully. Consider one of the options below or conduct your research to find the best insulation.

Insulation

Consider the Rockwool RW3 or RW5 for additional acoustic soundproofing, but this application is best suited for sound/recording studios rather than general office use.

Cladding

You will have a wide variety of cladding options for the exterior walls. Most will provide adequate weather protection, so it comes down to your aesthetic preferences.

The Eaves

What kind of roof do you want to build? They all serve the same purpose, but some may be easier to build and maintain. I chose a dual pitched roof purely for aesthetic reasons.

Flat Roof

This is the most basic structure, and you'll save money by only needing one side of guttering. Of course, if you want to build this style, you'll need to do your research, but this video is a good place to start.

Apex Or Dual Pitched Roof

It is not overly complicated and can be constructed in two ways. Either with the rooftops running longways, as on a flat roof, or upwards to the apex, as in my original design.

Think about how much overhang you want on your roof. A roof with a substantial overhang will provide more rain protection than a small overhang.

Can I Build a Garden Office Myself?

It is entirely possible to construct your own garden office if you are a competent DIYer. There are several approaches to this, and which you choose will rely on how much work you would like to do yourself and how much authority you want over the building's design.

You could build your garden office from scratch or purchase a kit. A few garden office suppliers sell their designs as kits that you can assemble yourself. What is included in these kits, and do the building specifications vary depending on the supplier?

The most popular pattern of garden office kit is the log cabin style building of interconnecting timbers, which is relatively quick and easy to build – you get a large building for a relatively small budget – but this style of building is not similar to other styles of garden office when it comes to thermal efficiency because it is not as well insulated and is often not even double glazed.

Other types of garden office kits only include the basic framework, which you will use to source materials and finish the interiors and exteriors of the garden office. This is a good option because you get a sturdy structure designed by professionals while also having the freedom to personalise the structure.

The final type of garden office kit is the total package, which includes everything you need to build and finish a garden office from the supplier, including the cladding, doors and windows, and interior finish.

It is worth noting that the complete kits we've seen do not include the foundation system because it is site-specific, but several structural systems would be ideal for the self-builder, such as modern plinth foundation systems.

You could design your own garden office if you want more authority over the building's appearance, shape, and finish than a kit provides.

When designing your building, you can do it like a pro by using Sketchup to create 3D models and drawings to work from. A free version of Sketchup is more than adequate for designing a garden office, and it has an easy-to-use interface.

Building Regulations & Planning Permission for a Garden Office

There are a few regulations in place that help stop you from constructing a structure that may have an impact on your neighbours, so check the UK planning portal before you begin.

Failure to follow these rules may result in removing your lovely garden office, so make sure you adhere to them. Also, check your property deeds, as there may be a covenant that prohibits building work in certain areas.

Furthermore, you can always double-check these restrictions with your local planning department and obtain relevant guidance. The following is a summary of restrictions for permitted development outbuildings.

• Outbuildings to the side of the property are not permitted development on designated land.
• Outbuildings are not allowed development within a listed building's grounds.
• Outbuildings are not authorised for development beyond the original house's main elevation.
• The term "original house" refers to the house as it stood on July 1, 1948. (if it was built before that date).

Outbuildings must not take up more than 50% of the total land area surrounding the original house. Sheds, outbuildings, and extensions to the original house must be considered when calculating the 50 per cent limit. When coming up with garden office ideas, many people choose to use their existing outbuildings for this reason such as a garden office shed or a garden office outbuilding.

Any new building must not be separate, self-contained living housing and must not have a microwave device to be permitted development. Outbuildings must be single-story, with a peak eave’s height of 2.5 metres and an overall height of 4 metres if they have a dual pitched roof, or 3 metres otherwise.

If the outbuilding is inside 2 metres of the property line, the structure's total height should not exceed 2.5 metres. In addition, to be permitted development in national parks, the Broads, Areas of Outstanding Natural Beauty and World Heritage Sites, the total area covered by any outbuildings more than 20 metres from any wall of the house must not take more than 10 square metres.

Types of Garden Office

Some cladding materials are highly resistant to the dangers. Others, on the other hand, are easily safeguarded. Finally, you can choose an engineered product that has been designed to last a long time without needing maintenance.

Softwood Treated Garden Offices

The entry-level timber cladding used on garden offices is fast-growing pine cladding, a honey colour in its natural state. It's simple to work with and could be used for various cladding profiles.

Pine cladding necessitates UV protection and resistance to rot, insect, and fungal attack. In its natural state, it is not a long-lasting cladding. Because softwood decking boards are readily available and easy to obtain, they are less costly than traditional timber decking.

PROS

✔ Simple to work with

✔ The least expensive option

CONS

✖ Doesn't last if others

Thermowood Garden Office

In this situation, the wood is roasted to extremely high temperatures, which preserves it. Garden offices clad in thermowood are frequently left unfinished. They accept them and weather to a silvery hue over time. Untreated pine weathering is less consistent than thermowood weathering.

Many garden offices with wood siding are painted, which keeps moisture out and keeps the colour consistent. Because the grain and knots in softwood panelling can be 'busy' for some people, the opaque finish of paint conceals them.

PROS

✔ Long life expectancy

CONS

✖ It is difficult to complete the job

Cedar Garden Office

Western red cedar is the most common choice for garden office cladding. This is because it is a durable wood with inherent insect or fungus resistance that does not require a décor treatment in most cases.

You can keep the natural redness if you apply an oil that helps protect against UV rays during the design stage. This is something that should be finished before exposing the wood.

PROS

✔ Aesthetically pleasing

✔ It is simple to maintain the natural redness if desired

CONS

✖ Pricey option

Siberian Larch Garden Offices

Siberian Larch's inherent resilience makes it an excellent choice for garden office cladding. This is partly related to the resins in the wood, which makes it resistant to rot and fungus attack. If left untreated, Larch will degrade to a silver-grey colour. The visible knots in the larch sheathing give the structure character.

Building an eco-friendly garden office is an especially appealing option because it has a lower carbon footprint than other cladding options.

PROS

✔ Popular selection

✔ Resistance to rot and fungus

CONS

✖ Must be kept up with

MDF Garden Office (Exterior Grade)

A few companies use exterior grade MDF products for building cladding. People frequently believe that MDF is an inner product that cannot withstand outdoor use; however, due to the resins used in its production, external level MDF is quite robust.

MDF is an outstanding cladding material because it is available in large sheets with few joints. Although unfinished outer grade MDF has a greenish tint, its polishing is perfect for painting.

PROS

✔ Smooth finish

CONS

✖ None

Hiring Contractors to Build a Garden Office Checklist

When hiring a contractor for a garden office, you must have faith in them. It is a large project with significant implications. Here are some things to look for to help you decide.

• They will be happy to show you around their previous projects. When they arrive, speak with the owners, and inquire about their experience. Ideally, you should see a recently finished job such as one that was completed some time ago. This will give you a good idea of the work quality you can expect.
• Request to speak with a few of their previous clients; this is a good sign if they are willing to provide you with a long list of names. When speaking with previous clients, simply inquire about their relationship with the contractor.
• When you get your loft conversion estimate, make sure your contractor is able and willing to give you a total breakdown of all the costs. That way, everyone is on the same page about the work that needs to be done and the costs.
• A good sign is a contractor who gathers information when you explain what you want to be done. It means that things are much less likely to be overlooked.

FAQs

Sources

https://aroominthegarden.co.uk/what-affects-the-cost-of-a-garden-room/
https://wood-create.com/2021/02/14/how-to-build-a-garden-office-from-scratch-on-a-budget/
https://www.gardenofficeguide.co.uk/build-your-own-garden-office/