DIY workshop – How to build a garden workshop from scratch

If you’re looking to expand your workspace with a new workshop then I’m sure this post is going to help. Maybe you’ve started a new hobby or you’d just like a little more space for an existing hobby, then you’re probably thinking about a garden workshop. You could buy a flat pack workshop but if you’re already quite handy the thought of building your own workshop is certainly appealing. A DIY workshop is easily achievable for anyone with basic DIY skills.

I’ve been through the process of building both a flat pack unit and building my own from scratch so I’d like to share these experiences with you and show you which I think is best.

Why build your own workshop rather than buying a flat pack workshop?

If you’re ready this post then you’re already thinking along the lines of building your own workshop. Here are a few reasons why I decided to build my own:

  • Better quality. My workshop feels much better built than my flat pack unit. The materials are thicker and more durable.
  • Stronger structure. The overall feel of the structure feels much more durable than my flat pack workshop. I can walk on the roof without the structure flexing and the walls are solid.
  • Better sound and thermal insulation. Thicker walls means sound and heat are retained much better.
  • Cost. It was cheaper to build my own workshop. Not by a massive margin but it was cheaper.
  • Better looking. Aesthetically I think my own built workshop is better looking.
  • Custom designs, shapes and materials. You can make exactly what you want in any shape you want. You’re not limited by the usual square or rectangle pre-manufactured buildings. Oval, triangle, heart shaped, the possibilities are endless.

Here are some of the cons to building your own workshop:

  • It takes a bit longer. Having to individually cut everything to size adds a fair bit of time to the build.
  • Tools. You’ll need a few more specialised tools to build your own workshop.
  • It takes time and patience to design, plan and source all your materials. (hopefully this post will help a little here)

How much does it cost to build your own workshop?

This is quite an open ended question as most of the costs will be determined by the size and overall quality of your workshop. Other factors such as insulation, electricity and base prep work will also affect the final price of your own workshop.

Prices will start from around £500 for a basic workshop measuring about 10′ x 8′. My workshop cost about £5000. It measures 22′ x 10′, is fully insulated and has double glazing french doors.

Firstly you’ll want to understand exactly what you want your workshop to be used for. This will help you design the exterior and interior aspects and help you budget this accordingly. I wanted a workshop to help support my hobby of building furniture so I needed a reasonable size to house suitable woodworking tools and store items whilst they were being produced. I decided to make a workshop that was about 22 foot long and 10 foot wide. The workshop I built myself had a pitched roof, double opening front doors and no windows. The pre-made workshop I purchased was 12 foot by 10 foot, had two double doors and two perspex windows.

Is it cheaper to buy a manufactured workshop or build your own?

From my examples I’m going to show you how you can make a workshop from scratch cheaper than you can buy a manufactured one. There are however a lot of different factors to consider here. Size, construction type, windows and doors, electrics and roofing types all play a part to the overall finish of your workshop. You could spend as little as £500 and as much as £10,000.

If you want a cheap workshop then you will have to sacrifice on things like insulated walls and use cheaper materials for the base, walls and roofing. It’s a good idea to set yourself a budget and know what size you want before you get started. See my other post here about calculating costs for self build sheds.

Do I need planning permission to build a workshop in my garden?

If you stick within the guidelines of the planning permission then you won’t need to apply for any. Here is a simple guide as to what you can and cannot build in your garden.

Check the Planning Portal, or contact your local planning authority before you do anything. The following is an extract from the UK planning portal:

Outbuildings are considered to be permitted development, not needing planning permission, subject to the following limits and conditions:

  • No outbuilding on land forward of a wall forming the principal elevation.
  • Outbuildings and garages to be single storey with maximum eaves height of 2.5 metres and maximum overall height of four metres with a dual pitched roof or three metres for any other roof.
  • Maximum height of 2.5 metres in the case of a building, enclosure or container within two metres of a boundary of the curtilage of the dwellinghouse.
  • No verandas, balconies or raised platforms (a platform must not exceed 0.3 metres in height)
  • No more than half the area of land around the “original house”* would be covered by additions or other buildings.
  • In National Parks, the Broads, Areas of Outstanding Natural Beauty and World Heritage Sites the maximum area to be covered by buildings, enclosures, containers and pools more than 20 metres from the house to be limited to 10 square metres.
  • On designated land* buildings, enclosures, containers and pools at the side of properties will require planning permission.
  • Within the curtilage of listed buildings any outbuilding will require planning permission.

*The term “original house” means the house as it was first built or as it stood on 1 July 1948 (if it was built before that date). Although you may not have built an extension to the house, a previous owner may have done so.

*Designated land includes national parks and the Broads, Areas of Outstanding Natural Beauty, conservation areas and World Heritage Sites.

How to build a workshop UK

Here we go folks. This is a step by step guide for building your DIY workshop in your garden.

This post has relevant links to materials and tools for those who are based in the UK. If you are reading this post from another country, don’t worry, all the content is relevant but you will need to look for your own suppliers.

Throughout this post you will see images of two separate builds. This is because I built a workshop and then a year or so later I extended it and added insulation. Images will jump around a little but hopefully they give you a good idea of what is going on and what is important to you.

You’ll need a few decent tools for this project including a decent Combi drill and impact driver.


I’ve completed a list of materials at the end of each section so that you can see exactly what I have used throughout the build.

Step One – The Base

To kick things off you will need to build a base. I’ve gone for a raised wooden frame supported on patio slabs. The timber used is quite thin at only 70mm which helped keep costs down. This is probably the most cost effective way. Other options might include a paving stone patio base, a gravel base to allow for drainage, a stone wall with cement foundations or a cement pilar style base.

I first cleared the area and levelled it off as much as possible using a spade and shovel. I then placed the four corner slabs and used the timber and a large spirit level to ensure everything was flat. I’ve used some excess sharp sand from another build to help do this.

If you are working with an uneven surface like a slope then you will need to dig in one side and raise the other side. You can use breeze blocks to help raise one side of the frame.

Extra slabs were added to ensure a nice secure frame. Digging and adding compacted soil and aggregate to ensure all the slabs are even is very important. this can be quite a lengthy process but is very important.

The image below demonstrates the basic wooden frame that I have used on my workshop. This wooden frame is topped with 18mm OSB board and will be covered with a moisture barrier membrane.

The size of the base is up to you but bear in mind that the OSB boards come in at 2440x1220mm size. Working with multiples of these can make life easier.

I cut the OSB board using a circular saw.

Once the base has been constructed then I’d recommend covering it with a weatherproof sheet.

Materials required for building the raised wooden base

You could increase the size of the timber used for the base to provide extra strength and additional space for insulation. Consider a 95mm wide board or even 145mm.


Or 145mm

Step Two – The Walls

Each wall section was constructed using 2×4” timber. These were pieces together leaving roughly a 600mm gap between each other. This would allow enough space for the insulation.

Each corner post was 90x90mm and provided the support for each wall to be attached to. I put up the 3 walls and left the front wall for a custom size in which the door could be installed.

I screwed 9mm OSB boards to the outer walls and covered these with a breathable membrane.

Normally you would then put some strips vertically down the outer walls to mount the cladding on but I didn’t do this to save money. However I would recommend doing so to allow for air circulation.

Here I am retro fitting the 9mm OSB

Measure the door and build a timber frame to support this. Centre this on the front of the building and complete the rest of the surrounding walls. This can also be finished as per the other walls.

Door and window frames should be built with double thickness timber. Simply join two pieces together to ensure a good strong frame.

I purchased my doors from Wickes: UPVC French doors

You can also find similar windows if you wish to add some: Windows

Cladding is the final step and can be fitted from the roof to the floor. The type of cladding you use is up to you. Log lap cladding or ship lap cladding are both great options. These were simply screwed in using a thin 4mm x 30mm screws. Some may wish to nail their cladding on.

Materials for the walls and exterior cladding

If you prefer the look of loglap cladding then take a look at these:


Step 3 – The Roof

Building trusses can be a little tricky and quite time consuming. Ensure the pitch of the roof isn’t higher than 2.4m to stay within building permission regulations. Start off by making one and then replicate that.

My walls were all 2m tall so the pitch of the roof was only allowed to be 40cm. Notches we’re cut into each rafter to allow a secure fit to the wall. These pieces were all secured with screws.

Screws (70mm) were inserted down into the top of the rafter and secured to the wall frame.

The top of the corner posts can be cut off when you have the roof rafters in place. Simply use a hand saw and cut at the same angle as the roof pitch.

OSB boards (18mm) were then secured to the rafters. The roof overhangs the walls by about 30cm all the way around. Another waterproof membrane was added to the roof before the felt.

The roof felt can be rolled out onto the roof and tacked in using clout nails. Make sure you start at the lower edges and overlap each roll by at least 3cm.

Materials for the roof

You can choose which size OSB board you want for the roof. The thicker the better in terms of sound and thermal insulation.

Additionally, it’s also important to guard against moss, read up on how to stop moss growing on roofs to ensure you don’t run into a problem further down the line.

The cladding

Finishing off the walls with suitable cladding is all that’s required to protect you from the elements. There is a great selection available from most local timber merchants. Red cedar is considered the best type of material for this application but it can be quite expensive. You can try a Douglas Fir instead as a cheaper alternative. Take a look at this Timber Merchant for some cut-to-size timber as it has many options available for exterior use. Wood Shop Direct will deliver nation wide but if you are local in Cornwall they are worth a visit for some top-notch advice.

Step Four – The Interior

Now it’s time to work on the interior. Running electrical wiring is the first stage. If you’re not familiar or comfortable with this then hire a professional. I found this image very useful when doing the initial wiring on my workshop.

I drilled 8mm holes through the support timbers and fed the electrical wires around the room to the locations I wanted electrical sockets.

I then placed all the insulation into the wall cavities making sure the electrical cable poked through. I used 50mm Rockwool RWA45 insulation for this job. It’s a great sound and thermal insulator. These insulation sheets should fit nicely into the 600mm wide gaps between the timber frame.

I used 2.5mm 3 core for the sockets and 1.5mm 3 core for the lighting. A small 2 way consumer unit was added along with a number of 13A sockets and lighting switches and pendant fixtures.

You might prefer strip lighting for better coverage. These LED strip lights are ideal for workshops.

Always have your electrical work signed off by a qualified electrician.

The consumer unit must be metal in a workshop.

2 way consumer unit

With electrical wiring run now it’s time to add the insulation.

Now a layer of plasterboard can be fixed to the walls and ceiling. I used 9.5mm plasterboard and 40mm plasterboard screws to fix these to the timber frame.

All the electrical fittings were secured to the walls and tested by a qualified electrician.

Once you have fitted all the plasterboard you should fill the gaps. You don’t have to skim the whole wall with plaster unless it’s looking very bad. I simply used some ready mixed plaster, joining tape and a 4 inch knife to join the boards and fill the gaps. Take a look at this YouTube video for help.

Electrical materials list

Here is a complete list of electrical materials I have used on this project.

Running power to your workshop

If you don’t already have power running down to your workshop area then you will need some armoured cable, of which the size and load will need to be determined by an electrician. A trench will normally have to be dug to install the cable and this will be wired into your consumer unit. The armoured cable is also covered in conduit to further protect it.

Interior materials

Finishing and insulating the walls.

You can also add a layer of OSB 3 board for added insulation on the inside.

Finishing off the workshop

The final job is to paint the interior walls, fit some laminate flooring and finishing off the exterior painting. I found a larger paint brush and a roller set made things much quicker here.

Here is the paint we used on the exterior: Cuprinol 5 year ducksback Black Matt Fence & shed Treatment 9L

We used a white silk paint on the interior: Dulux Pure brilliant white Silk Emulsion paint, 10L

Interior furniture and fixings

I decided to make a couple of simple workbenches and move my table saw workbench into this space. The construction is very straight forwards if you wanted to make these yourself. Alternatively you may wish to buy something and some racking for storage purposes.

Here are a few options:

Or build your own. This workbench is setup for mitre saw cutting.


It’s been a great experience building my own workshop. Challenging at times but mostly enjoyable, especially when the weather was nice. I’ve taken a look at some other builds on the internet for inspiration. This workshop build written by Karen Knox is a great little project and whilst it doesn’t go into quite the same level of detail, you will see a slightly different roof and base design if you’re thinking of a different approach.

Save money on your build

Save money on your build. I’ve been using TopCashback for all my online purchases which has enabled me to accumulate over £1000 in the last 3 years on all my spending. I simply just check TopCashback before making a purchase and use their link to generate money.

Here’s a look at my earnings to date.

To make the most of TopCashback I installed the Google chrome extension browser which notifies me when I am on a site eligible for cashback.

Another great way to save money is to buy in bulk and ensure you get free delivery. Both B&Q and Wickes offer free delivery on orders over a certain amount.

Thanks for reading

Having read all this you may be feeling a little overwhelmed. If not, great! I hope you enjoy your build as much as I have. If however you are thinking that a pre-fabricated building is better for you then take a look at some of these.

Project Timber 24×14 Pressure Treated Windowed Grandmaster Wooden Garden Shed
20 x 12 Insulated Evolution Apex Garden Office Shed Composite Cladding
20×10 Pressure Treated Diplomat Wooden Garden Summerhouse Offset Double Door
Total Sheds 16ft (4.8m) x 10ft (3m) Summer House Cabin Supreme Cabin