READY-MADE GREEN ROOF SYSTEM

Transcription

1 READY-MADE GREEN ROOF SYSTEM

2 TABLE OF CONTENTS ECCO Products 2 Who is ECCO? 3 Structure ECCOsedum tray 4 Specific properties of sedum tray 6 Specific green roof structure 7 Installation 8 Technical specifications 10 Questions and answers 12 ECCO PRODUCTS gravel stabilisation gabions green roofs garden lighting borders 2

3 WHO IS ECCO? Mission ECCO is a Belgian developer and manufacturer of innovative and user-friendly products with high added value for both the private and public sectors, and wishes to be a trendsetter on European level. Vision ECCO constantly analyses the market and is always furthering its development of intelligent products. We keep the entire process flow in-house (from development to sales) and can therefore apply stringent quality parameters ourselves. For the distribution of our products, we rely on a selective network of distributors that market our products all over Europe. This commercial network is supported by strong and innovative marketing tools. 3

4 STRUCTURE ECCOSEDUM TRAY 1 Drainage layer 4 Substrate layer A Horizontal click system 2 Water buffering layer 5 Vegetation layer B Vertical click system 3 Filtering layer B 2 A 1 See load book description on p. 9 Advantages Easy handling: installation of the green roof is very simple and can be done by one person. Low weight per m 2 : between 30 and 55 kg/m 2 (*). The ECCOsedum system can therefore be applied to virtually any existing roof. Installation may take place all year round, in contrast in situ sedum vegetation, in which case installation should be avoided in winter and summer. Easily removable if necessary, for example in case of water infiltration or roof maintenance. Constant substrate thickness. In contrast to a massive green roof, where this may vary between 1 and 8 cm and thus facilitate the growth of weeds. Nicely smoothed pressure points on the side of the tray to ensure an even better pressure distribution, in contrast to other ready-made systems. 4 (*) Weight is variable depending on saturation.

5 Vegetation layer The succulents are able to survive in a limited substrate layer (limitation of roof load) and have an easier time tiding over dry spells in comparison with other plants. The ECCOsedum system makes use of no less than 7 types of sedum which are fully rooted and grown thick (not giving weeds a chance). Mature plants, well-rooted in the substrate, are the best guarantee for a perfect, fully-grown green roof. Each type is planted in proportional quantities for a uniform distribution. Substrate layer The substrate layer has multiple purposes: it provides nourishment and water to the vegetation, supplies oxygen, and ensures anchoring of the roots. To this end, ECCOsedum uses roof garden substrate composed of: washed pumice stone 4-8 mm: 40%, lava 3-8 mm: 35%, coconut fibre: 15%, garden turf: 10%. As far as the vegetation is concerned, this is the most important layer. Its thickness is adapted to the requirements of the sedum types used and the climatic conditions of our climate zone. The following properties are essential: light high water buffering capacity balanced nutrient medium guaranteed constant quality Filtering layer This layer prevents the substrate from washing away. A non-woven, 150 g/m 2 polypropylene cloth retains the fine particles in the substrate. The weight of the cloth is selected to ensure that no ballast salts (see maintenance) can accumulate in the cloth. A cloth that is too heavy may cause plant death. Water buffering layer Water buffering helps the plants to survive dry spells. Therefore, the lower half of the tray ensures buffering of the rainwater. However, stagnant water during a period of rest (winter season) may cause rotting of the roots. The ECCOsedum system has provided a solution for this too, by means of capillary water buffering in a slightly expanded broken clay grain substrate (fractions: 4-8 mm). To prevent stagnant water from accumulating in the hollow sections of the clay substrate, drain holes have been installed at the top and bottom of this layer. Any excess water will be drained this way. The bottom drain holes are located at 1 cm from the bottom, so that noncapillary water can be stored as well. Tests have demonstrated that this does not have a negative impact on root growth and ensures an additional buffer. ECCOsedum = combination of the best working substrate + the lowest weight: weight per tray per m² dry state (overgrown with sedum) 8 kg 30 kg saturated state (overgrown with sedum) 12.5 kg 55 kg Drainage layer The drainage allows excess precipitation to be drained away on top of the roof membrane, without hindering catchment. 5

6 SPECIFIC PROPERTIES OF SEDUM TRAY 1. Horizontal click system A The trays have been provided with recesses and protrusions on the sides in order to prevent their moving relative to each other. 2. Vertical click system B Two tabs per tray ensure that all trays are anchored to each other and and blowing upwards is prevented. 3. Weight per m 2 roof surface During the design, the decision was made to keep the overall concept as light as possible. A heavy green roof needs a heavier support structure, which will affect the cost of the building. Depending on the amount of water it retains, an ECCOsedum system weighs between 30 and 55 kg/m Handling Trays of 0.25 m 2 per piece that weigh 8 to 12.5 kg, allow installation in a fast and back-friendly manner. 5. Roof inspection In case of a leak in the water repellent layer, it is difficult and expensive to find and repair the leak. This is true, and it is the biggest objection to green roofs. A part of the problems is caused by work that is subsequently done on the building with the roof seal being damaged. ECCOsedum is a system based on modular trays and therefore locally removable. 6. ECCOsedum can be installed all year around, In contrast to in situ sedum vegetation, in which case installation should be avoided in winter and summer. 7. Nutritional value sedum plants pollen The nutritional value of sedum pollen has not yet been studied in detail at this time. However, the nutritional value is more than just a determination of the calorific value; geometry and accessibility of the pollen grain have a fundamental influence as well. For example, microscopic research of maize pollen shows that they are shaped like a beach ball with a single opening. This explains, in part, why bee colonies are severely diminishing or even dying despite a large supply of maize pollen. In contrast, sedum plant pollen are easily accessible to bees, as a result of which bees are able to obtain sufficient nutritional value from them. 6

7 SPECIFIC GREEN ROOF STRUCTURE Roofing: asphalt, EPDM, PVC Root-resistant layer: ECCO PE400 Depending on the material used for roof waterproofing, it may be necessary to install a root-resistant sheet. Do not use a root-resistant sheet in case of EPDM or PVC, unless expressly instructed to do so by the manufacturer. Roof waterproofing that consists of asphalt membranes does need a root-resistant sheet. The root-resistant sheet prevents plant roots from damaging your roof waterproofing. Please consult your manufacturer. 3. Protective layer: ECCOprotect 400 A non-organic felted cloth is affixed to a woven PP cloth (dim. 2.1 m x 40 m). This layer consists of a cloth that provides additional protection to the roof membrane against sharp objects. Such objects could damage the cloth during installation. In addition, it provides an additional water buffering layer of approximately 300 ml/m 2. 7

8 INSTALLATION 1. Installing a root-resistant layer ECCO PE400, if necessary A root-resistant sheet does not always have to be used in case of EPDM or PVC, unless expressly instructed to do so by the manufacturer. 2. Installation of the ECCOprotect 400 protective layer These 2.10 m x 40 m roles are installed with 10 cm overlaps. The roles are available per m Installation of the ECCOsedum trays The trays are held together by a click system and are cut using a saw or grinding wheel. The RHP substrate is held together by the roots of the sedum plants. Do try to keep the water buffering layer intact during cutting, by cutting only up to half the height. 4. Vegetation-free zone In case of higher situated roofs, it is advisable not to have the ECCOsedum trays run all the way up to the eaves (vegetation-free zone of +/- 30 cm). This zone is then filled with roof gravel, preferably mm. Finer fractions are not recommended in order to prevent weed growth. This vegetation-free zone has multiple purposes: preventing that splashing precipitation which soils the adjacent building protecting the water drainage against clogging as a result of ingrowing vegetation preventing the vegetation from hanging over the eaves preventing any outbreak of fire from spreading from/to the vegetation preventing the vegetation layer or substrate from being blown away by wind forces preventing that the wind blows up the sides of the ECCOsedum trays 5. Cutting the sedum tray, if necessary Only cut the top layer, keeping the bottom layer (water buffering layer) intact 8

9 Installation of ECCOsedum on flat and inclined roofs ECCOsedum trays can be installed on both flat and inclined roofs, provided that two parameters are taken into account during installation: 1. prevention of washing away or shearing of the substrate 2. shearing of the entire green roof system by way of the incline of the roof. For the above reasons, the roof incline cannot be unlimited. Based on the gradient and the corresponding customised roof structure, the following categorisation may be made: Gradient between 0 and 3 (0 to 5%) In case of this gradient, the ECCOsedum system may be used without additional precautions. A gradient between 1 and 3 is considered a "flat roof" despite the small incline. Consequently, it is perfectly fine to use ECCOsedum here. Gradient exceeding 3 (more than 5%) This type is referred to as "pitched roof". In case of these roofs, the run-off precipitation may lead to surface erosion. This is not the case with ECCOsedum since it is delivered fully pre-cultivated and since the roots of the sedum plants keep the substrate contained, as it were. In case of a classic pitched green roof, the highest risk consists of the washing away of the substrate in locations where the greatest volumes of water are located (= lowest point of the green roof). This is prevented in the ECCOsedum system because any rainwater that washes away from one tray will never reach the next one. Between trays, the rainwater is immediately diverted to the drainage layer. Protection against erosion is not necessary at these gradients. Gradients higher than 15 to 20 (27 to 36%) Here, an additional system is installed to prevent washing away of the substrate layer. Such systems can be divided into two groups. (1) Systems that reduce the gradient by means of a step system (similar to a terrace structure) or (2) systems that divide the substrate layer into compartments by means of a slat system. The distance between adjacent slats is determined by the gradient. The slat systems can be further divided into: slat systems that are installed below the roof waterproofing: these can be carried out in wood and have a long lifespan, but require an additional protective layer if the slats do not have rounded edges. This is to prevent damage to the water-retaining layer. The additional water retention that may accumulate behind the slats will also have a negative effect on the shearing of the substrate layer. slat systems that are installed above the roof waterproofing: the slats are generally made from plastic. For inclines up to 11 (20%) they may also be made of wood. The wood will decay over the years, but as the substrate becomes rooted throughout, the substrate layer is firmly anchored. A slat system that is installed above the roof waterproofing has the advantage of not influencing the roof waterproofing and not causing water stagnation. 9

10 TECHNICAL SPECIFICATIONS General properties Fully pre-cultivated ready-made green roof trays Basic material trays: polypropylene (PP) UV light: the trays are equipped with a UV stabiliser Resistant against chemical substances Weight per tile: approx. 8-12,5 kg/tile Weight per m 2 : approx kg/m 2 Dimensions: 45 cm x 49.5 cm height 8.5 cm (4.4 tiles/m 2 ) Specific properties Drainage layer The structure of the tiles is designed to quickly and freely divert any rainwater that is not absorbed by the green roof system to the drain holes. Water buffering layer The pre-cultivated extensive green roof system solves this by means of capillary water buffering in a slightly expanded broken clay grain substrate (fractions 4-8 mm). To prevent stagnant (non-capillary stored) water from accumulating in the hollow sections of the clay substrate, drain holes have been installed at the top and bottom of this layer (overflow protection). Water that is not absorbed by the buffering system will simply wash away. The drain holes (4 per division) at the bottom of the water buffering system are placed at 1 cm from the bottom, so that non-capillary water may also be stored in this bottom cm. The volume of the water buffering layer is 6 litres per tile. Filtering layer A non-woven, 150 g/m 2 polypropylene cloth ensures that fine particles in the substrate are not flushed out. The weight of the cloth is selected to ensure that no fertiliser can accumulate in the cloth. 10

11 Substrate layer The substrate has multiple purposes. It provides nourishment and water to the vegetation, supplies oxygen and ensures anchoring of the roots. To this end, ECCOsedum uses roof garden substrate composed of: Washed pumice stone 4-8 mm: 40% Lava 3-8 mm: 35% Coconut fibre: 15% Garden turf: 10% Its thickness was adapted to the requirements of the sedum types that are used and the rainfall data of our climate zone. The substrate must meet the following requirements: Light High water buffering capacity Nutritious, but not overly so Guaranteed constant quality: marks of quality Volume/tray: 5.5 litres Vegetation layer The pre-cultivated extensive green roof system is delivered with at least 7 types of sedum plants, grown to a thickness of at least 80%. For transport of the pre-cultivated tiles to their destination, the roots of the sedum plants were not cut, thus ensuring their "survival" immediately after installation. All types were "slipped" in proportional amounts in accordance with the speed of rooting whereby each plant type occurs, more or less, just as often. Horizontal locking system The trays have been provided with recesses and protrusions on the sides in order to prevent moving relative to each other. Vertical locking system Two tabs per tray ensure that all trays are anchored to each other and and blowing upwards is prevented. 11

12 QUESTIONS AND ANSWERS Why install a green roof? Source: leaflet Agentschap Natuur en Bos (Nature and Forest Agency, A. Benefits for the community 1. Water management In urban areas, there is a high degree of waterproofing (= large proportion of pavement in comparison to the total area). As a result, little or no precipitation can penetrate the soil. Any such precipitation immediately flows to the sewer system via impermeable surfaces. Thus, even relatively small showers may cause a temporary overload of the sewer system, resulting in local flooding. This may be prevented by building larger sewers which may dispose of the water faster and in larger quantities. However, this is expansive and merely moves the problem to another area. Another solution is to immediately dispose of all precipitation (= increasing the retention of precipitation). This may be done in various ways, including through the construction of rainwater tanks or green roofs. The latter reduce the discharge of precipitation so that peak flows are lower, the sewer system is not (or less) overloaded and no (or less) serious flooding occurs. The ECCOsedum system provides an annual precipitation discharge of 50%. There is no difference in water discharge between flat and pitched green roofs with a gradient up to Air and water purification The urban environment is not only different from its surroundings in terms of climate, but also in terms of air pollution. A green roof can have a major influence on this as its complete system of vegetation, substrate and micro-organisms not only captures, but also degrades harmful substances such as carbon monoxide, benzene and dust particles. Green roof vegetation extracts dust and CO 2 from the air. In addition, it captures harmful substances, such nitrogen oxide, hydrogen sulphide, etc., and is able to encapsulate and immobilise noxious particles thanks to its stomata. In this way, green roofs contribute to a better living environment through air purification. Furthermore, precipitation contains many harmful substances. If contaminated precipitation flows through a green roof first, part of the pollution is filtered before it enters waterways. Consequently, green roofs and other greenery have an important protective function. 12

13 3. Habitat development Buildings and other infrastructures take up space, as a result of which loss of habitat always occurs. Despite the fact that green roofs are not a full substitute for lost natural habitat, they may form an important landscape element for both fauna and flora. Green roofs may serve as a temporary habitat (as a stepping stone or a temporary place of refuge), but they may also form a replacement or basic habitat. The extent to which certain plant and animal species are present depends on many factors, such as the type of green roof, the manner in which the vegetation was applied, and the presence of flora and fauna in the area. In any event, blooming sedum plants will strongly appeal to butterflies and other nectar-sucking insects. In other words, green roofs may contribute to the increase of various plant and animal species (so-called biodiversity). B. Benefits for the roof owner 1. Longer lifespan roofing A green roof lasts longer than regular roofing (twice as long even if compared to a flat roof with bitumen covering). The presence of the layer construction protects the roofing against: a. UV radiation: this breaks down materials due to photochemical reactions; in case of a green roof, however, the radiation is absorbed by the vegetation. b. Heating, freezing and temperature fluctuations of the roof: extreme and fluctuating temperatures cause friction in the roofing, as a result of which tearing occurs or seams may break (especially in case of bitumen roofing). A green roof tempers the temperatures through the presence of the vegetation and the substrate. This causes lower maximum temperatures and higher minimum temperatures, in addition to much smaller fluctuations in temperature. The extent to which temperatures are tempered depends on the thickness of the green roof. c. Uneven heating of the different roof layers: this results in blistering and deformation of the seals. This is not possible with green roofs, because fast and extreme fluctuations in temperature do not occur. d. Mechanical damage: roofs may become damaged by hail. In case of green roofs, the impact of the hail is absorbed by different layers. 2. Thermal insulation of the roof The above-mentioned lower maximum temperatures and higher minimum temperatures are a result of the insulating effect of the green roof. Therefore, not only is the roof waterproofing subject to a more moderate temperature regime, but heating costs in winter and cooling costs in summer will also be reduced. The effect of this is greatest in summer. 13

14 3. Sound insulation The green roof absorbs sound. However, the exact magnitude of the sound absorption is difficult to measure. The overall effect also depends on the surface and the structure of the greenery. 4. Visual benefits In addition to less extreme temperatures, higher humidity and cleaner air, green roofs also contribute to a better living environment and health through their visual effect. A view of greenery has a positive effect on the emotional state, and thus also on the physical health, of people. Furthermore, the look of a green roof changes with the seasons, resulting in a pleasant variation in views. 5. Environmentally friendly image By creating a green roof, businesses will develop a more environmentally friendly image. Working in a green environment also has a positive psychological effect and may contribute to increased job satisfaction and thus higher productivity. 6. Financial benefits Most people assume that a green roof is much more expensive than a traditional roof. This is true only if one compares the cost of purchasing a green roof to that of purchasing a traditional roof. Actually, the longer lifespan of green roofs ensures that the price difference is very small to nothing in the long term. Taking everything into account, green roofs are more economic than traditional roofs; the problem is that a part of the benefits cannot directly be expressed in monetary units. This can be calculated using adapted economic techniques; however, such research has not yet been performed with regard to green roofs. Still, it is certain that the value of these benefits is very high, not in the least because of their influence on matters of health. To lower the purchase costs of green roofs, the government provides financial support for the construction of extensive green roofs. This subsidy is offered through the cities/municipalities. For more information regarding the subsidy scheme, it is best to contact the environmental department of your city/ municipality. 14

15 So there are only benefits? Although the list of benefits is long, there are two things that must be considered: Heavier construction Installing a green roof adds additional weight to the roof construction. In most cases, the load-bearing structure is sufficiently strong to carry a green roof. However, in case of very large areas (industrial halls), a green roof is often impossible. Cost price The cost of purchasing a green roof is a factor not to be ignored. However, as a result of subsidies by the government, this is no longer (or to a much lesser extent) a valid objection. Please note: Subsidies are always dependent on the type of green roof. Is it possible to collect the rainwater from the green roof? For applications in the garden this is no problem, as the rainwater that passes the substrate layer, the filtering layer and the water buffering layer on its way to the rainwater tank is sufficiently filtered by these layers. The composition of the filtering cloth and the substrate has been engineered in such a way that washing away of fine particles is prevented. It should be taken into account, however, that rainwater carries organic particles from the green roof and can therefore not be used immediately for domestic applications, such as washing machines and toilets. Using a slow sand filter, you can make the water ready for use again. 15

16 Does a green roof need maintenance? If no fertilisers are administered to the plants, impoverishment of the nutritional value of the substrate (soil) will occur. This can be compared to a lawn: if you never fertilize your lawn, the grass will never be perfectly green and weeds will start to supplant the grass. If you wish to have a beautiful lawn, free of weeds, you must fertilise it. The grass will then grow so thick that weeds do not stand a chance. The same is true for the ECCOsedum green roof system. At the same time, sedum plants are much less demanding than a lawn. In order to optimally maintain a green roof, an inspection of the green roof is recommended at the end of the summer (end of September) and after the winter period (March-April). If weeds appear here and there after all, they must be manually removed (never use sprays). In addition, fertilisers must be used when the system requires it (impoverishment of the vegetation layer, primarily in March or April). It is advisable to use a specially developed slow-release fertiliser (Green Label Blackcasting) to prevent excess fertilization. The ECCOsedum system has been developed in such a way, taking into account the climate in which we live, that irrigation during dry periods is not required. However, at times when it has not rained for 14 days or more, we recommend that you water the green roof. Fertilisers should also be used. It is advisable to use a coated fertiliser of the Osmocoat type with a duration of effectiveness of 6 months (dose: 1.5 kg/10 m²). This type of fertiliser is available in most garden centres. Vegetation depending on season: photo taken in June. Vegetation depending on season: photo taken at the end of September. 16

17 What plants are used? In selecting plant types, the following parameters were taken into account: Aesthetic value (flowering, for example): large variety of sedum plants, at least 10 different types. Drought resistance as a function of substrate thickness, substrate composition and water buffer. Since each sedum type thrives best under slightly different climatic conditions, a large variety of sedum plants provides more security. Speed of multiplication, this in order to prevent overrunning by a certain type Regenerative capacity after extreme drought. Different flowering periods When pre-cultivating ECCOsedum, use is made of cuttings, these are offshoots of mother plants that are cut off. To determine the proper dosage of sedum cuttings for each variety, it is important to know how fast they multiply after planting (to avoid monoculture). By making use of growing fields (mother plants), each with one type of sedum plant, the correct mix of cuttings can always be guaranteed, which is important for a varied green roof. Types of sedum in ECCOsedum Sedum Immergrunchen Sedum Album Sedum Reflexum Sedum Sexangulare Sedum Acre Sedum Spurium Sedum Lydium The composition of the cuttings and the dosage of each type was carefully determined by greenery experts. In addition, the ECCOsedum system was subjected to extensive tests on rooftops and in simulated extreme weather conditions. After a series of tests, the final plant mix proved to be very effective. 17

18 In what way does the ECCOsedum roof system help to conserve the bee population? Bee mortality is caused by (in order of importance): the large amount of maize that is planted: maize has pollen with a very low calorific value, so that bees which assume that they have sufficient supplies for winter end up weakened by a lack of nutrition the presence of the varroa mite and parasitic fungus the use of pesticides. Note that the use of pesticides only comes third. Imidacloprid (Confidor), in particular, is subject to heavy criticism. Complaints have also been made with regard to the application of a mix of several pesticides. When examining garden plants, 57 substances were found, almost all legal, but classified by some environmental organisations as toxic and therefore as poisonous plants. As a result of this action, chains and supermarkets are required to deliver plants that are free of illegal and toxic substances. They are asking their suppliers to sign a statement to this effect. ECCOsedum trays are cultivated with absolute respect for beneficial insects. The time of application and the choice of pesticide is crucial in this regard. The ECCOsedum nursery registers pesticides, fertilisers and energy under the Ecas-certified MPS label. 18

19 Notes Do you need more information? Please do not hesitate to contact us: mail: tel: web: 19

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