FAQ

A green wall, also called a living wall or vertical garden, is a facade system covered with plants. It can be installed both indoors and outdoors and turns unused walls into climate-proof, green surfaces. SemperGreenwall systems are pre-cultivated, modular and equipped with a fully automatic irrigation system.

A vertical garden of Sempergreen contribute to air purification, a lower ambient temperature, heat regulation and urban biodiversity. Green facades are part of climate-proof and nature-inclusive building. They also have a positive effect on the people in the area by improving the working atmosphere or shopping experience, for example. They reduce noise pollution and lower the ambient temperature.

These living walls act as stepping stones for mobile arthropods, helping them migrate through urban environments. They also support the broader food web—arthropods feed birds, and naturally occurring predators maintain ecological balance.

Extremely. A study by Utrecht University found over 2,000 arthropods from 125 species on SemperGreenwalls in just 10 days—compared to only 500 on ivy-clad walls. That’s a 4x increase and proof that the rich plant diversity turns buildings into vibrant ecosystems.

Yes. A SemperGreenwall reflects about 50% of sunlight and absorbs 30%, reducing heat build-up. This can lower the surrounding temperature by up to 3 °C and cut air conditioning use by around 33%.

Yes. A SemperGreenwall Indoor acts as an effective sound barrier. Independent tests show it absorbs up to 85% of ambient noise (αw 0.85). Please note: the exact acoustic value depends on factors such as room size, ceiling height, construction and furnishing.

Yes. Less need for air conditioning in summer and heating in winter means significant energy savings.

Yes, installation is possible almost all year. Only in frost conditions the installation of outdoor systems is postponed.

Thanks to the efficient irrigation system, the plants only use the amount of water needed and are distributed evenly over the plant wall. No more manually watering the plants! Moreover, depending on the variant, the reservoir only needs to be refilled once every 2 to 4 weeks.

Sempergreen carefully selects strong, perennial species tested for each climate zone worldwide. For outdoor walls, hardy plants such as perennials, ferns and shrubs are used. For indoor walls, plant choices depend on daylight levels. Patterns, logos and custom designs are possible.

Yes, choose from our wide range of plant species, each with its appearance and unique properties.

The amount of water used per m² depends on factors such as plant type, exposure, wind, and season. On average, a SemperGreenwall requires about 1.8 litres of water per m² per day. This amount can vary: indoor walls with stable climates usually consume less, while outdoor walls exposed to sun and wind may need more.

Every SemperGreenwall is fitted with an integrated irrigation and nutrient system. Water flows through irrigation tunnels in each panel to guarantee even distribution. With the optional web-based module, irrigation can be monitored and adjusted online 24/7. Frost protection is available for outdoor walls.

Sempergreen or a local service partner takes care of the full installation. The modular Flexipanels are pre-cultivated in our own greenhouse with up to 90% coverage on delivery, ensuring an instant green result. A built-in irrigation system provides water and nutrients.

A green roof is a flat or pitched roof covered with vegetation, such as Sedum, herbs, or ornamental grasses. A green roof is also known as a vegetated roof, roof garden, or living roof. There are different types, each with its own structure, appearance, functionality, and benefits. Common variants are extensive (lightweight) green roofs and intensive (roof garden) green roofs.

A green roof offers many benefits: it retains water, purifies the air, reduces temperature, saves energy, increases biodiversity, and extends the lifespan of the roof. In addition, it improves people’s well-being and enhances the value of buildings.

An extensive green roof consists of a thin substrate layer (max. 15 cm) with a drainage layer underneath. This makes the system lightweight and relatively affordable.

Extensive green roofs are often planted with Sedum species, sometimes supplemented with herbs and flowers, such as in the Biodiverse green roof. Due to the thin build-up, these are classified as extensive or semi-extensive.

An intensive green roof, also known as a roof garden, has a thicker substrate layer (25 cm or more). This allows for planting shrubs and even trees, but it also makes the system heavier and more expensive.

A standard green roof system like Purple-Roof can hold back most of the rainfall during warm periods, reducing immediate drainage needs and easing stress on sewer systems. The Water Retention Boxes provide quantifiable storage capacity, enabling architects and builders to precisely design retention systems tailored to local rainfall demands or regulatory mandates.

No, a leakage is never caused by the green roof itself, but by roof coverings that are not waterproof or not root-resistant. Always check the quality of the roof covering beforehand. If you are unsure about its root resistance, it is recommended to install a root-resistant membrane as extra protection.

Yes, you can walk on a green roof in moderation. For example, performing annual maintenance such as fertilizing is no problem, even when stepping on Sedum plants. However, be careful during frost. We recommend avoiding walking on the vegetation when the plants are frozen, as this can cause damage. 

If you need to access the green roof more frequently or for longer periods, for example for building maintenance, we recommend placing roof garden tiles or stepping stones on the roof.

Yes, a green roof has an insulating and, above all, heat-regulating effect. It keeps buildings cooler in summer and can retain heat in winter, reducing energy costs. A green roof also dampens noise from traffic, aircraft and rain.

Yes! More and more provinces, municipalities, water boards and other government agencies are providing subsidies to encourage the use of green roofs. Contact your local government’s subsidy desk for more information.

Yes, green roofs provide sound insulation. The mix of plants, substrate and air layers absorbs and reflects sound waves. Research shows noise levels can be reduced by up to 8 dB, which sounds about 50% quieter to the human ear.

Yes, green roofs help lower city temperatures by reflecting sunlight and cooling the air through evaporation. In urban areas, summer temperatures can be 5–7°C higher than in rural areas. Research shows that increasing city greenery by 10% can significantly reduce this effect.

Yes, if the roofing is waterproof and root-proof, Sempergreen vegetation blankets can be applied to all types of roofing. This applies to flat and pitched roofs.

Higher efficiency: PV panels produce 6–10% more energy thanks to the cooling effect of the green roof.

Longer lifespan: Lower panel temperatures reduce wear and extend durability.

Biodiversity: Sedum and biodiverse roofs create habitat for bees, butterflies, and pollinators.

Sustainable building: Combining solar and green roofs contributes to higher BREEAM and LEED scores.

Improved rainwater management: Green roofs store and delay runoff, relieving urban drainage systems.

A blue-green roof combines rainwater retention and storage (blue) with vegetation (green). It temporarily stores rainwater and uses it for irrigation of the plants or releases it gradually into the drainage system. The blue layer is a water retention system that buffers rainfall. This stored water can later evaporate or be used to irrigate the green layer. The green layer, typically consisting of Sedum, herbs, or grasses, provides cooling, improves air quality, and enhances biodiversity. By combining water management with vegetation, a blue-green roof is a multifunctional solution for stormwater management, climate adaptation, and urban liveability.

A Detention Roof is an advanced green roof system designed to temporarily detain and delay stormwater runoff, even during extreme rainfall, while still supporting vegetation.

Unlike a standard green roof, the Detention Roof can store stormwater in its multiple layers and release it gradually. This prevents peak loads on sewers, reduces the risk of flooding, and ensures plants thrive even under saturated conditions. The system is particularly effective during heavy downpours and second-day storms, when traditional roofs quickly overflow.

A Retention Roof is a green roof system that stores rainwater permanently in its structure and makes it available for reuse, irrigation, or evaporation.

The water retained in the system is not immediately drained away but buffered for longer periods. This helps cool the environment through evaporation, supports plant growth, and reduces pressure on sewer systems. Retention roofs are often combined with smart drainage technology to regulate water levels.

The Sempergreen Biodiversity Package makes it easy to create additional habitat for insects and birds. It includes elements such as insect hotels, stones, gravel and selected plants that offer food and shelter. Because the package adds little weight, it is also suitable for lighter roof constructions.

A Sempergreen vegetation blanket consists of a coir fibre mat planted with different varieties of Sedum, and if required supplemented with (ornamental) grasses, herbs, wildflowers or host and nectar plants. The plants take root in the coir and a substrate specially developed by Sempergreen. The carefully cultivated vegetation mats boast at least 95% cover on delivery.

Yes. Depending on soil and slope conditions, we recommend specific system structures. Even embankments up to 45° can be greened with our reinforced Type T blanket.

For steeper slopes (10–45°), Sempergreen recommends using securing pins to anchor the Sedummix blankets, ensuring they remain in place on embankments, parks, or roundabouts.

Yes. Sempergreen Sedummix blankets can generally be laid throughout the year, making them suitable for flexible seasonal planning.

For flat or gently sloping ground (0–10°), dense soils like clay require an additional drainage layer beneath the Sedum-mix blankets. Well-drained soils such as sand may only need permeable substrate topped with the blankets.

Maintenance typically involves periodic checks, but the pre-grown blankets demand minimal upkeep. Over time, routine care may include occasional trimming, fertilising, or inspection for weeds.

Unlike planting individual ground cover plants, vegetation blankets are delivered 95% covered. This reduces installation time, minimises weeding and requires less maintenance, helping municipalities save on long-term budgets. 

Depending on the design and plant type (e.g., low mats vs. flower-rich blends), occasional trimming or maintenance may enhance appearance. Generally, however, the Sedum-mix blankets maintain themselves with minimal intervention.

Greener streets and buildings create more attractive neighbourhoods, increase property value, and foster social interaction while offering natural places to relax.

Sempergreen blankets require minimal care: annual fertilisation, watering during extreme droughts and occasional inspections. No mowing or frequent replanting needed – saving time and resources.

The plant mats, available in 60 × 200 cm, are delivered on pallets. You may collect from a nearby location or arrange delivery through Sempergreen. It’s recommended to install the mats promptly and protect them from intense sunlight while on the pallet.