Is It Cheaper to Buy or Build a Garden Room? Cost Guide
Thinking of adding a garden room but stuck between buying or building? Short answer: building can be cheaper, if you've got the time, tools, and a decent dose of patience. But for those short on weekends or DIY confidence, buying might save more than just your sanity.
We’re unpacking the true costs, hidden surprises, and whether you're better off with a hammer, or a hire.
The Short Answer: A Quick Cost Snapshot
Let’s cut to the chase.
DIY garden rooms can cost between £3,000 to £15,000, depending on how hands-on and budget-conscious you are. On the flip side, buying a prefab or fully installed garden room usually sits in the £10,000 to £50,000+ range.
When a DIY build can be cheaper
If you've already got the tools, don’t mind a few splinters, and actually enjoy the smell of fresh timber, DIY can slash the cost nearly in half. You're not paying builders, delivery crews, or project managers, just your own sweat equity.
This route works best for people with some building experience and a flexible schedule. If you’ve ever built a shed and still had fun doing it, you might be the perfect DIYer.
When buying a kit or fully-installed room is more cost-effective
Now, if you're not exactly Bob the Builder, or you're on a tight timeline, buying a kit or getting a team in might be the smarter money move.
Yes, it’s pricier upfront, but you’re saving on stress, rework, and possibly having to buy that circular saw you’ll never use again. Plus, professionals come with warranties and know-how, which often means fewer headaches in the long run.
Cost Breakdown: DIY Garden Room Build
Estimated Costs for Materials (Foundations, Timber, Insulation, etc.)
Building it yourself? Here’s a rough idea of where your money will go:
| Material | Estimated Cost |
|---|---|
| Foundations (Concrete or Pads) | £500 – £1,000 |
| Timber Frame & Cladding | £1,500 – £4,000 |
| Roof & Weatherproofing | £500 – £1,500 |
| Insulation & Internal Finish | £500 – £2,000 |
| Doors & Windows | £300 – £1,500 |
| Total DIY Cost Estimate: | £3,000 to £10,000+ |
If you’ve been Googling how much would it cost to build a shed in the UK, this gives you a strong starting point for a wooden garden room.
The Hidden Costs of a Self-Build (Tool hire, waste disposal)
Here’s where DIY starts to get sneaky. Sure, materials might seem cheap, but factor in things like tool hire, skip hire, or even site prep.
You might need a circular saw, power drill, scaffolding, and a few friends with strong backs. Add it all up, and you're looking at an extra £500 to £1,500 in hidden costs that don’t show on the initial budget.
The "Cost" of Your Own Time and Labour
Time is money, and DIY eats it up fast. Even a straightforward build can take 4 to 8 weekends, especially if you’re learning as you go.
If you value your Saturdays, or if the job drags out longer than planned, you might start wishing you'd just bought the thing ready-made.
Cost Breakdown: Buying a Prefabricated or Installed Garden Room
Average Costs for Different Sized Kits
Garden room kits and prefabs are easier to plan for. Here’s what to expect for different sizes:
| Size | Average Cost | Typical Features |
|---|---|---|
| Small (3m x 3m) | £10,000 – £15,000 | Basic insulation, standard windows |
| Medium (4m x 4m) | £20,000 – £30,000 | Better insulation, more sockets, extra windows |
| Large (6m x 4m) | £35,000 – £50,000+ | High-end insulation, lighting, full electrics |
So, when asking is it cheaper to buy or build a garden shed, remember this: buying is quicker, not necessarily cheaper.
Understanding 'Fully Installed' Prices
A “fully installed” garden room usually includes design, build, internal finish, electrics, and sometimes even plumbing.
While it costs more, £150 to £250 per m² for labour alone, you’re getting speed, reliability, and someone else handling the paperwork. No tool rental, no skip, no flat-pack disasters.
The Value of a Professional Guarantee and Warranty
One big bonus of buying? Warranties.
Many garden room companies offer 10+ years of structural and electrical cover. That’s a massive win if something goes wrong mid-winter or you plan to use it as an office year-round.
Beyond the Price Tag: What Else to Consider?
Skill Level and Expertise Required for a Self-Build
You don’t need to be a master carpenter, but you do need confidence in basic construction, electrics, and weatherproofing.
If you’ve never built more than flat-pack furniture, think twice before diving in. It’s fun, until your roof leaks.
Time and Speed: How a professional build is much faster
A pro team can have your garden room up and ready in just 1–2 weeks. A DIY job? Realistically, 4–6 weeks minimum, and that’s with steady weekend work and no major hiccups.
If you're in a rush, buying wins, hands down.
Quality of Finish and Long-Term Durability
Professionally built garden rooms often use high-spec materials, top-notch insulation, and comply with all local building regs.
That means better energy efficiency, longer lifespan, and fewer repairs over time. DIY builds can still be solid, but only if done properly.
Customisation Options: Bespoke Build vs. Kit Limitations
If you want to build your dream garden escape, with skylights, soundproof walls, and sliding doors, DIY or bespoke builds give you total control.
Kit rooms are more limited. Some let you choose finishes or add extras, but the layout is usually fixed unless you pay for a custom upgrade.
A Checklist to Help You Decide
Assess your DIY skills honestly
Be real with yourself. Have you ever built anything bigger than an IKEA wardrobe? If not, going full-DIY might not be the money-saver you think.
How much time can you realistically commit?
Do you have free weekends lined up? Or will this drag on for months? If you can’t give it consistent attention, a professional might be worth the extra spend.
What is your total, all-inclusive budget?
Don’t forget the extras, tools, paint, skips, wiring, permits. The “cheap” build can get pricey fast. Budget everything in from day one.
How important is a professional, warrantied finish to you?
Peace of mind matters. If you’re using this garden room as an office, gym, or chill space all year, a proper warranty and pro finish could save future hassle.
Our Verdict: Which Option Offers the Best Value for You?
So, what’s cheaper, buying or building a garden room?
If you’ve got the tools, experience, and time, building it yourself can absolutely save you money. Some people shave thousands off the cost this way.
But for others, the peace of mind that comes with a professional install, plus the speed and long-term durability, is worth every penny.
In the end, it's not just about price. It's about value, for your time, energy, and how you'll use the space. So choose the path that fits your life, not just your wallet.