Setting a Budget for Your Garden Room
Updated: 1 December 2025
Reading Time: 4 minutes
Setting a clear budget for your garden room project is essential. It helps you determine the best balance between space, design features, and personalisation, ensuring the final result meets your needs without unexpected costs.
Why Sharing Your Budget Helps Designers
Having a defined budget benefits not just you but also your garden room designer. It allows them to focus on delivering options that align with your wishlist. While some buyers hesitate to disclose their budget, fearing suppliers might inflate costs, reputable companies won’t take advantage of this. Instead, they may highlight where spending a little more could achieve certain features or suggest alternative ways to meet your goals using more affordable materials or design tweaks. This collaborative approach ensures you can make informed decisions and get the best value for your money.
Beyond the Building: Other Costs to Consider
While base prices for garden rooms are straightforward, the full project cost includes various additional expenses. Below are the most common factors to include in your budget:
Delivery Charges
Many suppliers offer nationwide services, but delivery policies vary. Some absorb transportation and accommodation costs into their quotes, while others charge for distances over a specific range—commonly 100 miles—with rates averaging around £6 per mile. For longer projects requiring overnight stays, additional charges may apply, often calculated as a flat rate or percentage of the total project cost.
Final Electrical Connection
Though garden rooms typically come pre-wired with sockets and lighting, connecting them to your home’s mains supply is often your responsibility. This process, requiring a qualified electrician, involves burying armoured cables, connecting to the fuse board, testing, and issuing Part P compliance certification.
Costs vary based on distance, with a 25-metre connection typically ranging from £1,400 to £2,500. Turnkey providers may include this in their quotes, while others leave it to you to organise, so consider this when comparing options.
Foundation Costs
Many garden rooms now include quick-install foundations like ground screws, which are often factored into quotes. However, some companies treat the foundation as an extra or require you to arrange it separately.
The cost depends on site conditions and foundation type. For example:
- Ground screws: Around £800 for a 2.5m x 2.5m room; ~£2,000 for a 5m x 3m room.
- Concrete bases: £1,500–£2,000 for smaller rooms; £2,200–£4,200 for larger ones.
Planning Permission Fees
Most garden rooms can be built without full planning permission, but it’s your responsibility to confirm. If permission is required, you can manage the application yourself, hire a planning specialist, or ask your supplier to assist. Expect to cover application fees even if the supplier handles the paperwork.
For structures built under Permitted Development rights, applying for a Lawful Development Certificate is advisable. This document proves compliance and can streamline future property sales. Use the Planning Portal’s fee calculator for the most up-to-date costs.
Interior Finishes & Electrics
Some suppliers exclude internal finishes and electrics from base prices, offering them as optional extras. This approach can make their initial quotes appear more competitive while giving you flexibility to customise. If opting for a shell design, budget for finishing the interior to your specifications.
Site Preparation
Suppliers often expect the site to be cleared of obstacles and vegetation before installation. Turnkey providers may include site clearance in their quotes, while others may leave this to you. If self building, consider costs for skip hire or clearing equipment.
Skips & Portaloos
For larger projects spanning weeks, suppliers may request a skip for waste and a portaloo for their team. Check whether these are included or will require additional budgeting.
Building Regulation Fees
In many cases, a garden room can be built without needing to apply for Building Regulations approval. However, it's important to note that your electrical system must comply with Part P of the Building Regulations.
If you are planning a larger garden room or one that will be used for sleeping, you will need to account for Building Regulation fees in your budget.
These fees can be difficult to estimate as they depend on the specifics of the project, including its cost and the work being undertaken. This is something you should discuss with your supplier early on — they may include these costs in their quote or require you to pay for them separately.
Insurance-Backed Warranties
While many suppliers offer warranties of five to ten years, some provide insurance-backed warranties for extra reassurance. These cover potential issues even if the supplier ceases trading. Depending on the supplier, the cost of this policy may be included or offered as an optional extra.
Final Thoughts on Budgeting
Proper budgeting ensures your garden room project stays on track and within your financial comfort zone. By accounting for these common additional costs, you’ll avoid surprises and be fully prepared to create a space that fits both your vision and your wallet.
