In this article, we are going to introduce you to the different options when it comes to self-building a garden room. Depending on how much work you want to do yourself, you can design a building from scratch or take the tried and tested method of buying a kit.
This is a long article, use these headings to jump to a section quickly:
Why would you self build a garden room?
95% of the garden room projects we feature on The Garden Room Guide have been supplied on a full installation basis. The customer chooses a company to work with, and they then handle the manufacture of the building and the installation in the customers garden. This is a quick process. Lead times are around 4 to 6 weeks, while on-site installation times are typically less than two weeks. In fact, many buildings we feature are fully installed in 1 or 2 days.
With these quick, hassle-free, streamlined services, why would you choose to self build a garden room?
One of the main reasons people choose to self build their garden room is to save money. By removing the installation component, you will significantly reduce the overall cost of your garden room.
The amount you will save will depend on the size of the building you choose, and the complexity of the building design. With designs that have a short installation time, you might save £1,500 - £2,000. More complex construction systems that typically have a longer build time you might save £2,000 - £5,000 depending on the building size.
The best way to see how much you might save is to ask companies to quote you for both a self-build option and on a full installation basis.
Building a garden room can be a very satisfying challenge. You will develop lots of new skills from installing foundations through to fitting doors and adding a roof covering.
Standing back and looking at a building that you have built, layer by layer is very satisfying!
While the experts can assemble their buildings in a matter of days, we can guarantee that it will take you more than a few days to build your first garden room. A key aim is to get the building temporarily weather tight as soon as possible. This means getting it to the stage of the breather membrane. Be realistic with what it will take to get to this stage and try to focus your efforts resources on getting the structure to this stage as soon as possible.
Get the room you want
If you choose to design your garden room from scratch, you will be able to tailor every aspect of the design to your specification. This is the most flexible option if you have clear ideas for your new room. However, there is quite a lot of flexibility when buying a kit too.
Often, when buying a garden room kit, you are left to choose the interior finishes. This gives you a blank canvas to make your mark on the interior. You might decide to plasterboard and skim the room to create the feel of a room in your house, or go a little off-piste and line the walls and ceiling with plywood for a more pared down look.
Two routes to self-building a garden room
There are two routes you could take when you choose to self build a garden room.
Design & specify the project yourself
If you want input into every element of the build, then you can design and specify the building yourself. This requires insight to the different materials and construction systems used by professional garden room designers.
We have your back here, our sister site the Self Build Garden Office Guide offers an ebook sharing our years of industry insight into the different construction systems and materials used by the pros.
Buy a garden room kit
The second route is to buy a garden room kit. A handful of garden room companies offer their buildings in kit form. This can be a very safe way of self-building as you are using a tried and tested building system.
The type of kit offered varies between suppliers
Some companies offer a bespoke design service similar to what they offer customers buying on a full installation basis. With this service, they work with you on the design and layout of the building. They then manufacture the frame and order the doors, windows and cladding and deliver it to you to put together.
The majority of self build companies, however, supply their standard designs in kit form. You still have a degree of flexibility, in that you choose the size you want and the positioning of doors and windows and they supply you with the kit.
You will find that all the parts are delivered in one go. So, you need to make provision for transporting them from the road to your back garden and for storing them safely, while leaving room to work. It is worth asking when you order the kit how much help the delivery driver will give you to offload and how many sets of hands are required to move the parts safely.
Different building systems
In garden room design, several building systems are used. You will find traditional timber framing used, structural insulated panels (SIP's), closed cassette panels which are a cross between the first two systems and log cabin systems with interlocking timbers. They all have their merits.
Traditional timber frames
With traditional timber framing, the core structure is made up with spaced timbers. The thicker the timbers and the closer together they are, the stronger the frame will be. Insulation is fitted between the framework on the inside of the frame. On the outside of the frame, a layer of structural board is installed. This adds stability and stops the frame twisting. Over this sheathing board, a breathable membrane is fitted. This protects the frame from the ingress of moisture while allowing it to escape from within the building.
Closed cassette frames are a cross between traditional timber frames and SIP's panels. As the name suggests, they are a closed panel which lock together with a tongue and groove style joint. A traditional timber frame has a layer of structural board on both the external and internal sides. Insulation is fitted between the timber framework. Often a fibre matting like Rockwool is used in this type of build-up. A vapour barrier is installed on the inner side of the insulation before the internal layer of structural board being added. A breather membrane is fitted over the exterior side of the membrane.
SIP's - Structural Insulated Panels
Structural Insulated Panels (SIP's) have become popular with garden room designers. Some companies use house quality SIP's while others have developed their own in-house versions.
With a SIP, two layers of structural board are bonded together with rigid insulation. They are cut into manageable size panels which slot together with a tongue & groove style joint. The panels slot over a timber footer plate with another run around the top of the panel.
Interlocking log cabins are another way to self build a garden room. Kits come in varying thicknesses from a very thin 24mm to 70mm. In our opinion, you should be looking at a log cabin kit with walls thicker than 45mm if you want to be able to use the room all year round.
With log cabin kits, the floor and roof structures can be insulated. This is often offered as an extra. The walls are not insulated; this makes the thickness of timber all the more critical. The thicker the wood, the better insulated the room will be.
Garden room kit companies
It is worth emailing or ringing these companies about their garden room kits; they don't seem to make the options clear on their websites:
Garden2Office specialise in Swedish garden rooms. Their highly insulated closed cassette panels and performance glazing have been designed for the colder Scandinavian climate. Garden2Office offer a self-build option alongside their full-service package. With the self-build option, you can have the same input into the design and layout of the building.
The Garden2Office team tell us their kits are popular with people who want the best possible building on a fixed budget. They buy the core structure from Garden2Office and then source the internal finishes and have the electrics fitted themselves.
The Garden2Office offer support to their self-builders. They can even send a 'Cabin Guru' who can help you with the build on a daily rate.
Garden2Office supplied this pitched roof building in kit form for a personal trainer who wanted to create a gym building so he could work with his clients.
He had a tight budget, so didn't line the interior out. Even so, the pared-down looks great!
Garden Affairs offer their extensive range of garden rooms as self-build kits. They way they price their buildings is that you pay for the core structure and then choose elements such as electrical package, factory painted doors etc. They have an installation service as an option too, so you can quickly see how much you will save by assembling it yourself.
Garden Affairs offer two ways to self build a garden room. You can buy one of their log cabin kits, which are made up with interlocking timbers and their Linea range which is a contemporary style garden room built using a traditional timber framing system.
Garden Room Living
Garden Room Living offer a bespoke design service for their self build kits. You decided on the size and layout you want along with the finishes and the Garden Room Living team will manufacture a kit, and deliver it to you to assemble.
Garden Room Living uses a traditional timber framing system for their garden rooms. They deliver the frame in manageable size panels, which will require 1-2 people to move.
Building With Boxes
Building With Boxes uses Hemsec SIP's as the core structure of their garden room kits. SIP's offer a highly insulated core structure that is coupled with double glazed doors and windows. They offer their kits in four standard sizes, but we are pretty sure they also provide the opportunity to customise the layout.
Check what is included in the kit
When researching your options, ask the companies what is included in their kit and how it will be delivered. Some companies only supply the core structure, including the breathable membrane. Some firms will include the doors, windows, external cladding and roof covering. Which together create the weathertight shell.
It is commonplace for you to have to source the internal finishes. Also, you often have to arrange both the first and second fix for the electrics. Some companies do, however, offer an electrical pack whereby they supply you with a length of armoured cable, and a set number of sockets and lights.
When it comes to finishes such as the exterior cladding, ask whether they will be cut to size for you and if you will be supplied with a few extra meters in case of damage etc.
Ask how the kit will be delivered to you. It is commonplace for the whole kit to be delivered in one go by lorry. It is a good idea to get an idea of how much space will be needed to store the kit and to ascertain where it will be delivered to. Some companies will deliver just to the kerb side, so you need to factor in walking it into your rear garden. Also, ask if the delivery driver will be able to help with moving the kit. If not, it might be advisable to ask some friends to be on hand that day.