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Fill out the form and give us brief details.
We will get back to you with an indicative SIPs extension cost, so you know what to expect.
Once you have an idea of the price of a SIPs extension, you can then make an informed decision.
Or call the experts today on 0330 166 0877
We will get back to you with an indicative SIPs extension cost, so you know what to expect.
Once you have an idea of the price of a SIPs extension, you can then make an informed decision.
Or call the experts today on 0330 166 0877
Maximise Your Space with SIPs
Traditional cavity wall construction typically uses up to 350mm of wall thickness, which can eat into your usable floor space—especially in smaller extensions. In contrast, SIPs (Structural Insulated Panels) use just 147mm of thickness while still exceeding modern insulation and strength standards.
In a 4m x 5m extension, this difference alone can free up around 2m² of additional internal space—enough for extra storage, a larger dining area, or simply a more open feel. With SIPs, you’re not just building faster and stronger, you’re building smarter.
Space gained with SIPs
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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.
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.
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.
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.
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.
Building a garden gym with an extension pack
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.
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.
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.
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.
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.
Dimensions
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 office project and would like more details of our extension kits or would like to place an order, contact our friendly team.
Email: sales@extensionkitz.co.uk
Phone: 0330 166 0877
Frequently asked questions
"Build it faster, stronger, warmer and smarter"
HEAD OFFICE
Cemetery Works, Cemetery Road, Radcliffe, Greater Manchester, M26 4FT
sales@extensionkitz.co.uk
0330 166 0877EXTENSION KITZ
We are an established, family run, innovative manufacturer and supplier of Structurally Insulated Panels (SIPs) for home extensions, annexes, pods, garden rooms, and modular educational buildings.
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