The pandemic made garden offices mainstream. What was once a niche luxury is now a genuine alternative to commuting or trying to work from the kitchen table.
But there's a lot between "I want a garden office" and actually working in one. Here's what's really involved.
Is a Garden Office Right for You?
Before spending thousands, be honest about these questions:
Will You Actually Use It?
A garden office is only valuable if you'll use it. Consider:
- Weather - Will you walk out in the rain? In winter?
- Routine - Do you have the discipline to "go to work"?
- Equipment - Can you move everything you need out there?
- Calls - Is the internet/phone connection good enough?
Some people thrive with separation between house and office. Others find it isolating or inconvenient.
Space Requirements
What will you actually do in there?
| Use Case | Minimum Size | Realistic Size |
|---|---|---|
| Basic desk work | 2m x 2m | 2.5m x 2.5m |
| Desk + storage | 2.5m x 2.5m | 3m x 3m |
| Two desks | 3m x 3m | 4m x 3m |
| Video production | 3m x 3m | 4m x 4m |
| Desk + meeting space | 4m x 3m | 5m x 4m |
Remember: you need space for the desk, chair, you (pushed back from desk), and anything else. 2x2m fills up fast.
Location in Your Garden
Consider:
- Distance from house - further = more cabling cost
- Sunlight - great for natural light, problematic for screen glare
- Privacy - from neighbours and from your own house
- Access - can delivery trucks get close?
- Ground conditions - slope, drainage, existing features
Planning Permission: The Rules
Most garden offices don't need planning permission under "permitted development" rights. But there are limits:
Usually Permitted (No Planning Needed)
- Single storey only
- Maximum 2.5m height (or 4m if more than 2m from boundary)
- Not covering more than 50% of garden
- Not at the front of your property
- No balconies or verandas
- Not used for sleeping accommodation
You'll Need Planning Permission If:
- Your house is listed
- You're in a conservation area
- You're in an AONB (Area of Outstanding Natural Beauty)
- The building exceeds size limits
- You've already used permitted development rights
- It's for "business use" with visiting clients (grey area)
Exeter Specifics
Parts of Exeter are conservation areas (city centre, some older suburbs). The East Devon AONB starts close to the city. If in doubt, call Exeter City Council planning on 01392 265223 - a pre-application enquiry is free for householders.
⚠️ Don't skip this step. Building without permission when you need it can mean enforcement action and having to remove the building entirely.
Types of Garden Office
Flat-Pack / Self-Build
Cost: £3,000-10,000
Pros:
- Cheapest option
- DIY-friendly (if you're capable)
- Delivered in parts, easier access
Cons:
- Assembly takes days
- Quality varies massively
- Insulation often inadequate
- May not be properly weatherproof
Pre-Built / Modular
Cost: £8,000-25,000
Pros:
- Professional build quality
- Properly insulated
- Delivered largely complete
- Quicker installation
Cons:
- Needs crane or hiab delivery
- Access can be a problem
- Less customisable
- Higher base cost
Bespoke / Custom Build
Cost: £15,000-50,000+
Pros:
- Exactly what you want
- Can match your house style
- Maximum customisation
- Often highest quality
Cons:
- Most expensive
- Longest lead time
- Requires architects/builders
- Planning more likely needed
What to Look For (Any Type)
Whatever you choose, check:
| Feature | Minimum | Ideal |
|---|---|---|
| Wall insulation | 50mm | 100mm+ |
| Floor insulation | Yes | 100mm+ |
| Roof insulation | Yes | 150mm+ |
| Windows | Double glazed | Triple glazed |
| Cladding | Treated softwood | Cedar/composite |
| Roof | Felt/membrane | EPDM rubber |
| Foundation | Concrete pads | Full concrete base |
The cheap options often skimp on insulation - then you spend a fortune on heating.
The Base: Don't Skimp Here
Your garden office needs a solid, level foundation. Options:
Concrete Slab
Best for: Larger buildings, permanent installations Cost: £1,000-3,000 Pros: Solid, level, permanent Cons: Needs digging, curing time, hardest to remove
Concrete Pads / Paving
Best for: Medium buildings, DIY-friendly Cost: £500-1,500 Pros: Easier than full slab, adequate for most offices Cons: Needs to be level, can shift over time
Timber Frame / Bearers
Best for: Flat-pack buildings, temporary options Cost: £300-800 Pros: Cheapest, reversible Cons: Can rot, needs treatment, may need adjusting
Screw Piles / Helical Piles
Best for: Difficult ground, slopes, minimal disruption Cost: £1,500-4,000 Pros: No digging, adjustable, works on slopes Cons: Specialist installer needed
💡 Pro tip: The ground in Devon is often clay, which moves seasonally. A proper foundation prevents your office becoming wonky over time.
Electrical Installation
Unless you're just using battery-powered devices, you need electricity.
What You'll Need
Basic setup:
- Power supply from house
- Consumer unit (mini fuse box) in office
- Several double sockets
- Lighting
- RCD protection
For proper home office:
- Dedicated circuit from main house
- Multiple socket positions
- USB charging points
- Network cable (or good WiFi)
- Heating circuit
DIY vs Professional
This is NOT a DIY job. Garden office electrics must be:
- Installed by a Part P certified electrician
- Properly earthed
- Protected by RCD
- Certified and notified to building control
Bodged electrics are dangerous and will cause problems when you sell your house.
Typical Costs
| Installation | Cost Range |
|---|---|
| Basic supply + 4 sockets + lights | £1,500-2,500 |
| Full setup + heating circuit | £2,500-4,000 |
| Add network cabling | £200-500 |
| Add EV charger circuit | £300-600 extra |
The cost depends heavily on distance from your house. 5 metres is cheaper than 30 metres.
Heating and Cooling
Devon isn't the coldest place, but a garden office gets cold in winter and hot in summer.
Heating Options
| Type | Running Cost | Install Cost | Notes |
|---|---|---|---|
| Electric panel heater | Medium | £50-150 | Simple, no install needed |
| Oil-filled radiator | Medium | £80-200 | Portable, no install |
| Electric underfloor | Medium-High | £500-1,500 | Best with good insulation |
| Air source heat pump | Low | £2,000-4,000 | Most efficient, highest upfront |
| Wood burner | Low (fuel) | £1,500-3,000 | Cosy but needs flue |
| Air conditioning (heat/cool) | Low | £800-2,000 | Heating + cooling in one |
For most Exeter garden offices, a wall-mounted air conditioning unit (which also heats) is the practical choice - handles both summer and winter.
Cooling
South-facing windows = oven in summer. Consider:
- Blinds - essential for any office
- Openable windows - cross-ventilation
- Air conditioning - if heat is serious
- External shading - overhangs, trees, awnings
Internet and Connectivity
Your garden office needs reliable internet. Options:
WiFi from House
Cheapest option, variable results
- Works if office is close to house
- May need WiFi extender or mesh system
- Signal through walls/glass is weaker than you'd think
- Test before committing
Ethernet Cable
Best for reliability
- Run Cat6 cable from router to office
- Needs burying or protecting
- Rock-solid connection
- Allows wired devices
Powerline Adapters
Middle ground
- Uses electrical wiring to extend network
- Works better than expected
- Performance depends on wiring quality
- Easy to set up
4G/5G Router
Independent connection
- Separate SIM contract
- Works regardless of house distance
- 5G coverage in Exeter is growing
- Backup option if main internet fails
For video calls and large file transfers, wired ethernet beats everything else.
Interior Fitting Out
Once the shell is up and powered, you need to make it a workspace:
Walls and Ceiling
Many garden offices come with unfinished interiors. You might need:
- Plasterboard lining - for a proper finish
- Painted OSB - cheaper, industrial look
- Tongue and groove - traditional, warm feel
Flooring
| Type | Cost/m² | Notes |
|---|---|---|
| Laminate | £15-30 | Easy to fit, wipe clean |
| Vinyl plank | £20-40 | Waterproof, good with underfloor heating |
| Carpet | £10-30 | Warm but harder to clean |
| Engineered wood | £30-60 | Premium look, avoid near doors |
Furniture and Setup
Consider:
- Desk positioning (screen not facing windows)
- Cable routing (before furniture goes in)
- Storage solutions
- Lighting positions
- Meeting area if needed
Total Cost Reality Check
Here's what a garden office actually costs in Devon:
Budget Option (DIY-Heavy)
| Item | Cost |
|---|---|
| Flat-pack building (3x3m) | £4,000 |
| Base (DIY concrete pads) | £500 |
| Electrical installation | £2,000 |
| Interior finishing (DIY) | £500 |
| Heating (panel heaters) | £200 |
| Total | ~£7,200 |
Mid-Range (Pre-Built)
| Item | Cost |
|---|---|
| Pre-built insulated office (3x3m) | £12,000 |
| Concrete base (professional) | £1,500 |
| Electrical installation | £2,500 |
| Interior finishing | £1,000 |
| Air conditioning | £1,500 |
| Total | ~£18,500 |
Premium (Bespoke)
| Item | Cost |
|---|---|
| Custom-built office (4x4m) | £25,000 |
| Foundation (screw piles) | £3,000 |
| Full electrical with network | £4,000 |
| Air conditioning | £2,000 |
| Premium interior finish | £3,000 |
| Total | ~£37,000 |
Common Mistakes to Avoid
Buying Too Small
"I'll just need a desk" - then you add a printer, filing, a second monitor, a chair for visitors... Buy bigger than you think you need.
Ignoring Insulation
A cheap, poorly-insulated building costs more to heat over its lifetime than a properly insulated one costs upfront.
Skipping the Base
"It'll be fine on the grass" - no, it won't. Invest in a proper foundation.
DIY Electrics
Illegal, dangerous, and will bite you when selling. Use a qualified electrician.
Forgetting Access
Check the delivery route. Can a flatbed lorry (or crane) get to your garden? Measure gates and side passages.
Not Testing WiFi First
Before committing, test your WiFi signal where the office will go. Solving connectivity problems afterwards is frustrating.
The Installation Timeline
Realistic timeline from decision to working:
| Stage | Duration |
|---|---|
| Research and quotes | 2-4 weeks |
| Planning check (if needed) | 2-8 weeks |
| Order and lead time | 4-12 weeks |
| Base preparation | 1-5 days |
| Delivery and assembly | 1-3 days |
| Electrical installation | 1-2 days |
| Interior finishing | 2-5 days |
| Total | 3-6 months |
Don't believe "ready in 2 weeks" claims. Plan for delays.
Need help with your garden office setup? From assembly to interior fitting to desk installation - I can help with the bits that aren't specialist electrical work. Call 01392 964094 or get a quote.
Sam Hembury
Sam is the founder of Hembury Contracting, providing professional handyman services across Exeter and Devon. With years of experience in property maintenance, he shares practical tips to help homeowners tackle common tasks.