Buying a green roof: what to look out for?
Buying a green roof is a sustainable choice. A green roof can buffer water, protect the roof and contribute to biodiversity. Those looking to order a green roof would do well to check a few points beforehand. Not every roof is the same, and the construction of a green roof also varies from situation to situation.
This guide explains what a green roof is, what types there are, which sedum roofing material is right for your roof and what a green roof costs. It also names when buying a green roof is a logical choice within the broader green roof offerings.
What is a green roof?
A green roof is a roof to which plants are applied. In practice, this often involves an extensive green roof with sedum because it is relatively light and requires little maintenance. Sedum is a succulent plant that can store water and is highly resistant to sun and drought.
Green roofs roughly come in two varieties:
Extensive green roof: lightweight, sedum, limited construction and maintenance.
Intensive green roof: heavier, often with more substrate and planting such as grass, perennials or even shrubs.
For many homes, barns and outbuildings, an extensive green roof is the solution of choice.
Also read: What is a green roof?
Is your roof suitable?
Before you going to buy a green roof or order a green roof, it is important to check if your roof is suitable. The most important points are bearing capacity, roof type and water drainage. A green roof weighs more than standard roofing, especially when it becomes saturated with water.
Key control points:
Load-bearing capacity: Check that the structure can support the additional weight, including water loads.
Roof type: Flat roofs are usually most suitable. Slightly sloping roofs may also be suitable, provided the structure is stable and the edge trim is done properly.
Water drainage: proper drainage and a clear area around drains help prevent blockages and water problems….
In doubt about whether your roof is compliant? Then have a specialist take a look or check out the guidelines in our knowledge base on roof requirements.
What does a green roof cost?
The question “What does a green roof cost?” depends on several factors, such as the system chosen, the surface area, the accessibility of the roof and whether you build it yourself or have it installed. The cost is usually expressed as a price per square meter.
- If you install it yourself, you can expect to pay between €40 and €70 per sq. ft.
- With professional installation, the price is usually between €60 and €100 per m².
This price includes all layers such as the protective layer, drainage, substrate and sedum planting. The exact price also depends on the material, the accessibility of your roof and additional requirements.
More on this: What does a green roof cost per m²?
What type of green roof best suits your situation?
Anyone who wants to buy a green roof, usually choose an extensive system with sedum. This is a lightweight and low-maintenance solution. Within sedum systems, there are several options, each with its own advantages.
- Lightweight green roofs: Specially designed for roofs with limited carrying capacity. Ideal for garages, extensions or gazebos.
- Sedum mats: These offer instant green results. They are quick to apply and contain a mix of mature sedum plants.
- Cassette systems: Convenient ready-made trays with sedum, substrate and drainage in one. Perfect for do-it-yourselfers.
Read more: Lightweight green roof
Buying a green roof: build it yourself or have it installed?
A buy a green roof does not automatically mean that it must be installed by a professional. Many systems are suitable for self-installation, provided the preparation is done properly and the construction for each layer is correct.
Building your own is often appropriate when:
the roof is easily accessible
you order the superstructure and materials in full
You work accurately and follow instructions
Having it installed is often wise when:
the roof is large or complex
There is a sloping roof or many details
Certainty is desired around planning, finishing and execution
Want to make a choice based on your situation? Then read on to the page about installing it yourself or having it done.
Also read: Install green roof yourself or have it done?
Don't forget the maintenance
A green roof is low-maintenance, but not maintenance-free. With periodic monitoring, the vegetation remains healthy and water drainage continues to work properly.
- Remove leaves and debris
- Check the water discharge
- Add fertilizer as needed
Proper maintenance extends the life of the structure and roofing.
Buy green roof with subsidy
Yes! In many municipalities in the Netherlands, you can get subsidies for installing a green roof. These allowances can be substantial and make the investment more attractive. So always check with your municipality to see if you qualify and what the conditions are.
Common mistakes when ordering a green roof
- Focusing only on price without looking at quality or suitability
- Forgot to check if the roof can handle the weight
- No consideration of drainage
- Being late with grant applications
- Choosing an inappropriate system for the type of roof
Avoid these mistakes and do sufficient research or get proper advice from our specialists.
Ready to buy a green roof?
Buying a green roof or ordering a green roof is best done with a clear choice of system, proper construction and appropriate edge finishing. Checking the suitability of the roof in advance and comparing the costs carefully will result in a green roof that will last and function well.
Frequently Asked Questions
Pay attention to whether your roof has sufficient bearing capacity, what type of system suits your situation (such as lightweight or cassettes), and whether you want to install it yourself or prefer to have it done. Also check to see if you qualify for a subsidy.
The cost is usually between €40 and €70/m². DIY systems are cheaper (from €41.90/m²), while professional installation costs more, but often offers guarantees. Read more about the cost per m²
Your roof should have sufficient load-bearing capacity (especially when saturated with water), have good drainage, and ideally be flat or slightly sloped. In doubt? Have a specialist take a look or use our roof check.
Do you have a lightweight roof structure? Then go for a lightweight green roof. Want quick results? Choose sedum mats. Do-it-yourselfer? Then cassette systems are perfect.
Also excited about sedum?
Check out our knowledge base or social media and keep learning!
