Garden Gyms

The benefits of garden gyms

Our extension kits are ideal for garden gym projects, creating smart, warm and energy-efficient outdoor rooms for exercise and fitness training. Our bespoke extension pack contains all the materials that a builder needs to create a dedicated space for fitness in any size of garden.

A private gym will remove all those barriers that make it difficult to get into a good exercise routine.

A garden gym is open 24 hours a day, and owners have the convenience of crossing the garden for a workout or to lift some weights whenever they feel like it.

Home gym owners have the luxury of opening the gym door for a blast of fresh air and nature when things get heated. When the British weather turns wet, exercise can continue with the added bonus of looking at a beautiful green space.

Our extension kits with SIPS panels offer the flexibility to build a garden gym to accommodate any type of health and wellness activity. You can design the space around cardio or resistance equipment or create a zen space for yoga or Pilates. 

In addition, a garden gym created with one of our extension kits will be a stylish addition to your garden space.

What does an extension kit for a garden gym contain?

Our extension kits contain SIPS panels cut to the exact dimensions that you need for your garden gym project and full instructions on how to assemble them. 

What are SIPS panels?

Structural insulated panels, or SIPS, are an innovative alternative to traditional brick-and-mortar or timber-framed construction methods. 

SIPS comprise two structural facing boards sandwiched together with highly insulating foam. The panels are extremely strong, light and energy efficient and are fabricated to customer specifications in our own factory. 

The garden gym can be made to any size, and our SIPs extension kits offer unrivalled versatility of design for extensions, conservatories and garden buildings. 


Building a garden gym with an extension pack

Our extension packs offer a building solution for all types of garden rooms, including home gyms, and have several advantages over more traditional building methods.

Quick to construct 

The SIPS panels for your project are manufactured at our factory according to your specifications and are supplied ready for speedy assembly on-site. 

Once the panels for the home gym have been fabricated, we assemble them in the factory, check the quality and then disassemble them, numbering each piece. This coding system makes the installation of your garden gym quick and easy.

Although they are extremely strong, the SIPS panels are light enough to manoeuvre easily, making handling and assembly easy for small teams and in tight spaces. This makes the construction time much faster than traditional brick or timber frame garden gyms.

Many customers reuse existing foundations for their extensions, but a freestanding new build, like a garden gym, can be placed on a concrete base. 

An extension kit can be assembled and ‘dry’ within 2–3 days, ready for the installation of plumbing and electrics and interior fixtures and fitting. The whole process is usually finished in around 3–4 weeks.

This innovative construction method makes the extension kits suitable for trade professionals and competent amateurs. We can also work with the customer to provide installation by our experienced teams.


Energy-efficient and good for the environment

Garden gyms built with SIPS panels are always comfortable and warm due to the thermal efficiency of the panels. This is due to the panels’ layered construction and the insulation, which can be either 97 mm, 122mm, 147mm, or 172mm in thickness. 

This high degree of insulation and thermal efficiency reduces the heating energy requirement of our extension kit garden gyms by up to 60%. 

In addition, the way that the panels are secured together makes the construction extremely airtight, with no gaps for heat leaks or draughts. 

SIPS construction is also a great environmental choice, as the panels are made using timber from plantations managed by the FSC. In addition, their production doesn’t require as much energy and raw material as other structural building systems. 

Low maintenance but high performance

SIPS construction panels require little maintenance as they do not degrade over time. The panels are up to seven times stronger than timber frames and can stand up to the worst of weather conditions.  They are also resistant to fire, exceeding British Fire Safety regulations. 

Our SIPS products are subject to rigorous testing by building and materials standards experts, and we are happy to offer a ten-year guarantee on our extension kits.

Planning and Designing Your Garden Gym

Garden gyms are usually visible from the house and are an important feature in the garden, so the aesthetic appeal of the structure is important. 

The bespoke nature of the SIPS extension kit means that we can produce a design to fit whatever space the garden can accommodate and the design requires. Customers often employ architects on their home gym projects, but our CAD design team is happy to help customers work their own ideas into a usable design.

We offer a wide range of external finishes for garden room gyms. 

Brick slips can complement the style of the house and area, or you could choose aluminium cladding to make a strong style statement.

We also offer a choice of roof tiles to finish your project in style.

Other options include UPVC cladding, timber cladding, ceramic tiles, cement board and render.

We can provide consumer boxes, electrical cables, lights, sockets and switches as part of the extension kit if required.

Creating a functional workout space

There are many factors to consider when designing a functional garden gym, and the versatility of our extension kits allows for a high level of customisation.

The location of doors and windows

Windows and doors can have a positive impact on the experience of using a garden gym, and they can be placed wherever wanted in our structurally insulated panels. Windows that look out onto the most beautiful part of the garden will give an inspiring view. It is also useful to fit windows to maximize privacy while exercising. Doors should be placed so that they open without using up too much valuable floor space. 


Garden gyms should not overwhelm the garden with their size, but they do have to be large enough to fit all the required gym equipment. Whatever space is available, we can fabricate an extension kit to fit it. Don’t just consider the floor plan. Ceiling height is also important, as some exercise machines are raised from the ground.

Flooring and Surface Options

We leave the garden gym freshly plastered so that owners can decorate it any way they wish. Many customers like to have a soothing, uncluttered interior design so that they can focus on their exercise. 

Integral storage space is popular in garden gym design so that movable objects like yoga mats and exercise balls can be tidied away, leaving the floor clear of clutter. 

If the garden gym is to be used for floor-based activities like yoga, comfortable and warm flooring will be required. 

Inspiring Garden Gym Ideas

You can find inspiration for your garden gym here.

Next Steps

If you are planning a garden gym project and would like to find out more about our extension kits, you can contact our friendly team for great advice.


Phone: 0330 166 0877

Obtaining a quick quote

You can obtain an indicative quick quote by completing the form below:

Contact Us

Frequently asked questions

How much space do I need for a garden gym?

The size of the garden gym is determined by the amount of space you have available in your garden. The panel for the gym can be cut to virtually any size in our factory.

What if I hit a problem when I’m constructing my garden room?

You are not on your own with your extension kit. 

Our Build Assist service is available to trade and own build customers. One of our experienced team will come out to your project and advise on any problems you may be having.

Do Extension Kitz garden rooms meet building regulations?

When they are correctly installed, all our kits comply with current building regulations. It is the responsibility of the person assembling the extension to ensure that the garden gym is built properly and that essential work, like laying the base and installing the electrics and external cladding is up to standard. 

If you plan to include a bathroom in the gym, then you will need to organise plumbing.

It is best to check this with your local planning authority. It may depend on the proximity of your gym to neighbouring properties.

Will I need planning permission for a garden gym?

If the garden building is just for family use, you probably won’t need to request planning permission, but if you are in any doubt, it is best to check with your local planning authority before work begins.

We have a lot of experience with planning permission, so we will be able to help you through the process. 

Can I use a garden gym during all seasons?

Your gym will be fully insulated and warm enough for winter workouts, whatever the outside temperature.

Will a garden gym add value to the house?

A garden room of any kind is a great home investment. 

A garden gym will be a stylish and quality product that will stand the test of time, meaning that the next owners of the property will be able to enjoy the benefits of an active lifestyle in the garden gym for years to come.

How much does a garden gym cost?

Home gyms are no longer just for rich celebrities, and an extension kit is a cost-effective way to maximize your health and fitness.

Are extension kits suitable for any other garden room projects?

Customers have used extension kits to build a variety of garden buildings, and this method of construction is ideal for a garden office, art studio, dance studio or summer house.