External Works for a New Build: Costs at a Glance
Driveway, terrace, fence and garden are missing when the prefab house is up – and with them a considerable block of costs. This guide shows which items count as external works, which price ranges to reckon with per trade, how the rule of thumb of 10 to 15 percent of the building sum works and where own work saves the most – all amounts only as a range, as of 2026.
Once the prefab house is standing, the plot is often still a building site: the driveway, terrace, fence and garden are missing – and with them a considerable block of costs. These outdoor facilities (Außenanlagen) are regularly underestimated in a new build, because they are usually not included in the house price. As a rough guide, around 10 to 15 percent of the construction sum applies as a customary range. This guide shows which items belong to it, which price ranges you should reckon with per trade, how the rule-of-thumb percentage works and where DIY work saves the most – all amounts only as ranges, as of 2026.
What all counts as outdoor facilities?
Short answer: Outdoor facilities include all the work around the house: the paved driveway and parking space, the terrace and paths, the enclosure with a fence or hedge, the garden design with lawn and planting as well as the outdoor lighting and the necessary drainage. Often added to this are terrain modelling, the application of topsoil and, depending on the plot, retaining walls or rainwater management. Each item has its own price range, which depends heavily on material, area and region – an early overview prevents individual items from disappearing in the budget.
Important to know: with a prefab house, outdoor facilities are almost never included in the house price, not even with turnkey offers. They count among the costs that arise in addition to the house – similar to the site connection and ancillary building costs. How these items fit into the overall calculation is shown in the overview of ancillary building costs. And with the cost calculator you can work through your project including outdoor facilities and a reserve.
Do not treat as a leftover item
Plan the outdoor facilities into the overall budget from the outset. Anyone who only notices after moving in that there is no money left for the driveway and garden often lives on a building site for years. The 10-to-15 percent rule is a good starting point for the buffer.
What costs should I reckon with per item?
Short answer: There are no reliable flat rates – the costs depend on area, material and regional craftsman prices. That is why only ranges and cost drivers can seriously be named per item. The driveway can cost many times as much, from cheap water-bound surfacing to expensive natural stone, and it is similar with the terrace and fence. Lawn and planting are comparatively cheap and well feasible as DIY, whereas earthworks, drainage and electrics quickly become a large item.
Typical outdoor facility items (only as a range, as of 2026)
| Item | What it includes | Cost driver | DIY? |
|---|---|---|---|
| Driveway / parking space | sub-base, paving or surfacing | area, material | rather a specialist firm |
| Terrace | sub-base, surfaces, edging stones | size, premium surfaces | partly |
| Fence / enclosure | fence, gate, hedge | length, height, material | mostly feasible |
| Lawn / garden | topsoil, lawn, plants | area, planting | well suited |
| Lighting / power | conduits, lights, sockets | scope, earthworks | specialist firm |
| Earthworks / drainage | modelling, drainage | terrain, slope | rather a specialist firm |
The choice of material is the strongest lever for cost and appearance. For the driveway the range runs from grass-grid pavers via concrete paving to high-quality natural stone; for the terrace, simple concrete slabs are considerably cheaper than porcelain stoneware, wooden decking or natural stone. If you set deliberate priorities – for example a prestigious terrace but a plain rear garden fence – you keep the budget under control without skimping on the area seen daily. Anyone who wants to extend the outdoor facilities with a swimming pool is best planning it in early – the most important steps are explained in the guide to building a house with a pool.
Cost the house and outdoor facilities together
Anyone who plans the driveway, terrace and garden in from the start avoids expensive extras after moving in. Compare the offers of several prefab house manufacturers from our network free of charge and keep the overall budget in view.
How does the percentage rule of thumb work?
Short answer: As a rough rule of thumb, around 10 to 15 percent of the pure construction sum applies as the frame for all outdoor facilities – with a medium-sized project, that quickly means a low to mid five-figure amount. A level plot with a plain design lies at the lower edge, a sloping plot with retaining walls, a paved driveway and elaborate planting is well above it. The rule does not replace a detailed calculation, but it helps to estimate the order of magnitude and to hold a realistic buffer.
Understand the percentage rule as a starting point, not an end result. As soon as the rough design is settled, you should obtain concrete offers from garden and landscaping firms for the larger trades and have them structured comparably – that is, with the same areas, materials and sub-bases. Only this way do you recognise whether a cheap price is based on a leaner execution. For a first, neutral orientation on customary services in garden and landscaping, the consumer advice centre (Verbraucherzentrale) provides information.
What cannot be retrofitted comes first
Everything that later disappears under paving or lawn – conduits for power and water, drainage, foundations for later structures – belongs in the first stage. These preparatory works cost little but save the expensive tearing-up of finished surfaces. The garden itself can happily grow later.
Where can you save on the outdoor facilities?
Short answer: The greatest saving potential lies in clever staged planning and realistically deployed DIY work. First lay the functionally necessary foundations that cannot be retrofitted – earthworks, conduits, drainage and the paved driveway. The terrace and paths follow as a second stage; lawn and planting can be well postponed to later. This way you spread the expenditure over several years. Simple tasks such as laying a lawn, planting or setting up fences can be done yourself with a little skill, saving several thousand euros.
- Build in stages and spread the expenditure over several years.
- Lay foundations that cannot be retrofitted, such as conduits and drainage, first.
- Take on lawn, planting and simple fences as DIY.
- Leave demanding trades such as the paving sub-base and electrics to the professional.
- Honestly include material, tools and your own time in the calculation.
How much DIY work really pays off and how to realistically assess the so-called “muscle mortgage” (Muskelhypothek) is explored in depth in the guide to DIY work when building a house. Do not overestimate either your time or your skill: a self-laid garden devours many weekends, and expensive rented tools can erode the supposed saving. Anyone with a demanding job is sometimes better off commissioning the specialist firm and using their own time differently.
Plan outdoor facilities cleverly
Short answer: The outdoor facilities shape the first impression and outdoor living comfort – and take up a noticeable part of the budget. Allow around 10 to 15 percent of the construction sum as a frame, obtain several offers for the larger trades and work in clearly separated stages. Use DIY work where it is realistic, and lay the foundations that cannot be retrofitted first. This keeps the project financially manageable and your plot matures step by step into a finished home.
Do not forget that the outdoor facilities are closely interlinked with the rest of the construction costs: earthworks, drainage and site connection interlock. So work through the overall budget carefully – a cost calculator helps to capture all items including a reserve. As guidance for the house price itself, the current prefab house prices 2026 serve. Anyone who also wants to roof over a parking space will find the options in the guide to prefab garage and carport. Also check in good time which preparatory works, such as conduits or foundations, you can have carried out during the house build – that is almost always cheaper than a later retrofit. With a realistic plan, the outdoor facilities turn from a feared budget hole into a well-manageable construction phase that visibly increases the value of your property.
From the structural shell to the finished home
The driveway, terrace and garden round off your building project – most cheaply when they are considered from the start. We put you in touch with suitable prefab house providers from our network free of charge and without obligation, who also place the outdoor facilities transparently.
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