Green roofs have gained popularity among Irish homeowners looking to enhance their outdoor spaces with eco-friendly features. This guide explores the three main approaches to adding living roofs to garden sheds and bin stores: DIY construction, ready-made kits, and pre-built options with green roofs already installed.

What is a green roof and why add one to your garden storage?

A green roof (also called a living roof) is a layer of vegetation planted over a waterproofing system installed on top of a flat or slightly sloped roof.

For garden sheds and bin stores, they offer several benefits:

• Enhanced aesthetics that blend storage structures into your garden landscape
• Improved biodiversity by creating new habitats for insects and birds
• Better rainwater management through absorption and slow release
• Extended roof lifespan by protecting the waterproofing membrane
• Additional insulation for the structure beneath
• Contribution to reducing urban heat island effect

With the EU acknowledging green roofs for the first time in the Energy Performance of Buildings Directive, there’s growing regulatory support for these sustainable solutions, though residential structures often have exemptions from requirements that apply to larger buildings.

Three approaches to adding a green roof to garden storage

1. DIY green roof construction

Building your own green roof gives you complete control over the design, materials and cost. This approach works well for those comfortable with basic construction and gardening skills.

What you’ll need:

• A structurally sound shed (check our garden sheds collection for suitable bases)
• Waterproof membrane (EPDM is recommended)
• Root barrier layer
• Drainage layer (typically permeable matting or gravel)
• Filter membrane to prevent soil washing away
• Lightweight growing medium
• Appropriate plants (sedums, mosses and native wildflowers work well)
• Edge restraints to contain the system

The DIY process:

First, assess structural integrity. Before adding a green roof, ensure your shed can support the additional weight. Most extensive green roofs (the thinnest type) add approximately 60-150kg/m² when saturated.

Next, waterproof the roof. If your shed roof isn’t already waterproofed, apply a suitable membrane. EPDM rubber is durable and relatively easy for DIYers to work with. Do not skip this step because proper waterproofing prevents moisture damage.

Once waterproofed, install a root barrier layer over the membrane to prevent plant roots from penetrating it. Above this, add a drainage medium that allows excess water to flow away while retaining enough moisture for plants.

Position a filter membrane to prevent soil from washing into and clogging the drainage layer. Then add a lightweight substrate specifically formulated for green roofs, typically 5-10cm deep for extensive systems. Choose drought-tolerant, shallow-rooting species suitable for the Irish climate, and finally install edging to contain the system and provide a neat appearance.

DIY green roofs are most economical, with materials costing approximately €25-50 per square metre, excluding the waterproofing membrane if needed.

2. Green roof kits

For those seeking a middle ground between DIY and pre-built options, green roof kits offer convenience while still involving some assembly.

Kit systems offer pre-measured components designed to work together, a simplified installation process, and are often lighter than traditional DIY systems. Most include planting guidance and contain similar layers to the DIY approach but with standardized components designed for easy fitting. Some include pre-grown sedum mats that simply roll out onto the prepared surface.

The installation process generally follows the same steps as the DIY approach, but with components that are designed to fit together more easily. Many kits come with clear instructions and sometimes video tutorials.

Kits typically cost €60-120 per square metre, depending on the system complexity and whether pre-grown vegetation is included.

3. Pre-built garden sheds with green roofs

The most convenient but often most expensive option is purchasing a garden shed or bin store with a green roof already installed.

Pre-built options offer professional installation of all components, structural design specifically engineered for green roof weight, warranty coverage for both structure and roof system, and immediate results with no DIY skills required.

When selecting a pre-built green roof shed, look for appropriate drainage provisions, quality of waterproofing system, plant selection suitable for Irish conditions, proper edge detailing, and maintenance requirements and support.

Summerhouse24 specialises in high-quality timber garden buildings like our large double garden shed which can be adapted to support green roof systems with proper planning and reinforcement.

Pre-built options typically cost 30-50% more than standard equivalents but eliminate installation concerns and often include warranties covering the entire system.

Suitability for Irish conditions

Ireland’s climate is particularly well-suited to green roofs due to regular rainfall that helps sustain vegetation, mild temperatures that allow year-round growing, and limited extreme weather events that might damage systems.

When planning a green roof in Ireland, consider drainage capacity which is essential during heavy rainfall periods. In exposed locations, additional measures may be needed to secure the green roof system against wind. Native species adapted to local conditions will thrive with minimal maintenance.

Maintenance requirements

Maintaining a green roof on garden storage is relatively straightforward. In the first year, water during establishment (first 6-8 weeks) unless rainfall is sufficient, remove any unwanted plant species that may appear, and check that drainage outlets are clear.

For ongoing maintenance, inspect twice yearly (spring and autumn), remove any tree seedlings or invasive plants, clear drainage outlets of debris, and consider occasional fertilisation (once yearly) with slow-release fertiliser designed for green roofs.

Most extensive green roofs require about 2-4 hours of maintenance per year once established.

Considerations before installation

Before proceeding with any green roof option, consider several important factors:

Ensure your structure can support the added weight of a saturated green roof. When building a wooden garden shed or selecting a pre-built model, consider the roof load capacity.

Green roofs work best on flat or low-pitched roofs (up to about 20° without special retention measures). Steeper roofs require additional systems to prevent substrate slippage.

Consider how you’ll access the roof for occasional maintenance. Low structures like bin stores are easily reached, but taller garden sheds may require a ladder.

Think about where excess water will drain. Proper base preparation can help manage runoff.

While small domestic structures generally don’t require planning permission, it’s worth checking local regulations, especially in conservation areas.

Cost comparison

Approach	Approximate Cost Per m²	Pros	Cons
DIY	€25-50 (materials only)	Lowest cost, complete control	Requires skills, time-consuming
Kit System	€60-120	Simplified installation, consistent results	Limited customisation options
Pre-built	30-50% premium over standard sheds	No installation worries, professional finish	Highest initial cost, limited design options

Making your decision

The right approach depends on your specific circumstances.

Choose DIY if you have basic construction skills, you’re working on a tight budget, you enjoy hands-on projects, and you want maximum control over materials and plants.

Choose a kit if you want simplicity but still enjoy some DIY, you need assurance of compatible components, you’re seeking a balance between cost and convenience, and you want some guidance but still want to be involved.

Choose pre-built if you prefer a complete solution with minimal effort, you want warranty coverage, you need immediate results, and you’re concerned about getting the technical aspects right.

Conclusion

Adding a green roof to garden sheds and bin stores is a rewarding project that combines environmental benefits with aesthetic appeal. Whether you choose the DIY route, a kit system, or a pre-built solution, the result will be a storage structure that complements your garden while contributing to biodiversity and sustainability.

For high-quality timber buildings that can serve as excellent bases for green roof projects, explore Summerhouse24’s range of garden sheds and outdoor structures, all crafted from sustainable Nordic spruce and designed for the Irish climate.