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8/8/2019 Green Roof Guide v2
http://slidepdf.com/reader/full/green-roof-guide-v2 1/24
Guide to Green Roofs
Visit us at: 11 – 12 FEBRUARY MANCHESTER CENTRAL
BSECTHE BUILDING
SCHOOLSEXHIBITION & CONFERENCE
09
03 - 05 march 2009, earls court, london
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Contents
What is a Green Roof? . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .1
ABG and Green Roofs . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .2
The History of Green Roofs . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .3
Types & Terminology - Extensive . . . . . . . . . . . . . . . . . . . . . . . . . . . .4
Types & Terminology - Intensive . . . . . . . . . . . . . . . . . . . . . . . . . . . . .5
Types & Terminology - Brown . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .6
Types & Terminology cont. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .7
Components . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .8
Components cont. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .9
Extensive Green Roof Drainage - Finesse Roofdrain . . . . . . . . . . . .10
SUDS and Rainwater Attenuation . . . . . . . . . . . . . . . . . . . . . . . . . . .11
Intensive Green Roof Drainage - Finesse Deckdrain . . . . . . . . . . .12
Benefits of Green Roofs . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .13
Benefits of Green Roofs cont. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .14
Barriers & Myths . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .15Barriers & Myths cont. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .16
Design Considerations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .17
Design Considerations cont. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .18
The Future . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .19
Summary . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .20
ABG Ltd E7 Meltham Mills Road Meltham West Yorkshire UK Tel: 01484 852096 Email: [email protected]
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Definition:
“A Green Roof is an intentionally Vegetated roof”
Sounds simple and in essence it is,provided you seek expert guidance
along the way. Finding the rightcompany to assist you at each stage of
the process is the difference betweenthe success and failure of the project.
This brochure is designed to be asimple introduction to Green Roofs andwill hopefully be of great use as a pointof reference.
For project specific advice please
contact our experienced andknowledgeable team direct;
Tel: 01484 852096
Email: [email protected]
Web: www.abgltd.com
1. What is a Green Roof?
ABG Ltd E7 Meltham Mills Road Meltham West Yorkshire UK Tel: 01484 852096 Email: [email protected]
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2. ABG and Green Roofs
ABG Ltd are a UK based
manufacturer and supplier of specialist geosynthetic materials,offering an extensive range of
geocomposite drainage products,geotextiles, geomembranes, andseveral specialist SUDS related
systems.
We first became involved in Green Roof projects approximately 20 years ago
when developing and launching ourown range of products specifically withGreen Roofs in mind. Since this timewe have supplied products to projects
throughout the UK, Ireland & mainlandEurope. Products supplied includeover 1,000,000 m² of geocomposite
drainage for both extensive & intensiveGreen Roofing projects.
Over the years we have developed a
number of long term relationships withfellow suppliers and installers which inturn has enabled us to offer a complete
ABG Green Roof package specifically
tailored to the needs of the client.
We pride ourselves on being a pioneerand innovator of environmentalsolutions. This includes being a
contributor to CIRIA C644 'BuildingGreener Guidance' which focuses onthe use of Green Roofs.
ABG are working to develop a UK
specific Green Roof which is tailored tothe geographical location and climaticconditions for the UK. We have
established development partnershipswith the University of Sheffield, TheUniversity of East London and
Groundwork UK. These partnershipswill investigate and develop theenvironmental benefits of Green Roofsand provide guidelines and training on
best practice. We will also develop aUK system with native plants toencourage local biodiversity with focus
on sustainable drainage systems.These will consider the hydrology andmaximise the attenuation of water to
encourage plant survival and growth
whilst alleviating storm water run off.
ABG Ltd E7 Meltham Mills Road Meltham West Yorkshire UK Tel: 01484 852096 Email: [email protected]
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3. The History of Green Roofs
ABG Ltd E7 Meltham Mills Road Meltham West Yorkshire UK Tel: 01484 852096 Email: [email protected]
When hearing the term 'Green Roof'people quite often assume that
this is a relatively new concept aimedat helping to counter the effects of
climate change. You may be surprisedto know that the concept of GreenRoofs date back as far as the 6thcentury BC (as depicted below).
More recently, the 20th century saw anincrease in the number of flat roof areas. This was partly due to theutilization of concrete in buildings.The knock-on effect was an increase inthe number of terraced roof gardens.
The 1950's saw the first real period of development in Green Roof technology.This development continuedthroughout the 60's and 70's, meaning
that by the 1980's any technicaldifficulties had been overcome and theGreen Roof as we know it was born.
As our counterparts in mainlandEurope and America have continued toincrease the number of Green Roofsthrough legislation and incentives, theUK has fallen behind. This isbeginning to change.
A combination of progressiveurbanisation and climate change,resulting in more intense rainfall hasincreased the volume of rapid run-off
from hard surfaces. This has beenhighlighted by the recent floodingwhich devastated the South Yorkshireand Humberside areas during 2007(see adjacent picture). Green Roofshave an important role in mitigatingthese effects by forming a sustainable
drainage system (SUDS).
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4. Types & Terminology - Extensive
Y ou are no doubt aware that there
are various types of Green Roofsand a number of terms commonly usedto describe them. But what do they
actually mean?
CharacteristicsExtensive Green Roofs are probably
the most common type of Green Roof. An extensive roof consists of a shallowlayer of substrate, typically 20mm to
200mm deep and a variety of droughttolerant hardy plants/vegetation.
Also referred to as a turf roof or sedum
roof
MaintenanceExtensive roofs are relatively self-
sufficient and are not designed andconstructed with the intention of beingtrafficked by pedestrians. Thereforeaccess to the roof tends to be limited
other than for occasional maintenance.Vegetation should be selected with thisin mind.
ABG Ltd E7 Meltham Mills Road Meltham West Yorkshire UK Tel: 01484 852096 Email: [email protected]
VegetationMosses, herbaceous plants,sedums and grass.
Waterproofing & root
barrier
Vapour barrier(Optional)
Leak detection layer(Optional)
Roofdrain 25Stores and drains water,incorporates Geotextile filtertop and attenuation &
protection blanket bottom.
20-200mm substrate0-200mm substrate
LightweightRoofdeck
Insulation
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Unlike extensive Green Roofs an
intensive Green Roof can be assimplistic or as complex as the clientdesires.
CharacteristicsIntensive roofs consist of a deep soillayer, typically 150mm to 1500mm.
Due to this soil layer there is greaterscope when it comes to planting. Theroof can be viewed very much like atraditional garden area and within
reason can be landscaped accordinglyto include trees, lawns, flower bedsand paved areas.
Also referred to as a roof garden or
living roof.
MaintenanceGenerally speaking when it comes tomaintenance an intensive Green Roof requires the same level of care and
attention as any traditional garden.
5. Types & Terminology - Intensive
ABG Ltd E7 Meltham Mills Road Meltham West Yorkshire UK Tel: 01484 852096 Email: [email protected]
150-1500mm substrate50-1500mm substrate
Roofdeck
Insulation
Vegetation A range of plants includingtrees and bushes.
Waterproofing & root
barrier
Vapour barrier(Optional)
Leak detection layer(Optional)
Deckdrain 25Drains water, incorporatesGeotextile filter top.
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ABG Ltd E7 Meltham Mills Road Meltham West Yorkshire UK Tel: 01484 852096 Email: [email protected]
The term Brown Roof is commonlyused to refer to a roof where the
vegetation is intended to replicate theexisting brownfield habitat.
With an increasing number of
developments being undertaken onbrownfield land, Brown Roofs canpartly mitigate this loss of habitat.
CharacteristicsThis type of roof can be seeded like
the intensive or extensive roofs or self colonised. Please note that seedingdoes increase the biodiversity potentialof the roof in the short term.
Also referred to as a biodiverse or
rubble roof.
MaintenanceSimilar to that of an extensive Green
Roof. Minimal maintenance isrequired. Aggregate & vegetationwould be determined by the
biodiversity objective the client would
like to achieve.
6. Types & Terminology - Brown
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Semi intensive/amenity
There are many projects where theGreen Roof does not fit neatly intoeither an extensive or intensive
category. These include some of thecharacteristics of each type and aretermed semi intensive or amenity roofs,
as they are usually intended forrecreational purposes.
The roof can include hard and softlandscaping which can have a variable
depth and type of substrate. Trees andshrubs that require deeper soil can beaccommodated in planted or raised
beds.
An amenity roof often includes watermanagement by means of SUDS,
attenuation, drainage layers, rainwaterharvesting and irrigation.
This can and should be designed with
the geographic location andattenuation requirements tocomplement the UK's environmental
needs.
Podium Decks
Many modern developmentsincorporate landscaped roofs, atterrestrial level, for example above
basement areas and shoppingprecincts. These areas are commonlyreferred to as a podium decks.
The deck areas themselves help createadditional usable space in populoustowns and cities, as car parks orrecreational parks. Whether the
intension is to create a hard or soft
landscaped area it is important to
consider the design implications of thedeck. Key considerations include:protection of the waterproofing,
drainage, water retention, outlets anddesign loads.
For large areas such as car parks or
recreational spaces it is imperative thatconsideration is given to provision of adequate subsurface drainage below
the topsoil layer and paving. In manycases a geocomposite drainage layerprovides subsurface drainage andprotection to the waterproofing.
7. Types & Terminology cont.
ABG Ltd E7 Meltham Mills Road Meltham West Yorkshire UK Tel: 01484 852096 Email: [email protected]
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ABG Ltd E7 Meltham Mills Road Meltham West Yorkshire UK Tel: 01484 852096 Email: [email protected]
8. Components
Waterproofing & InsulationSelecting an appropriate waterproofing
and insulation system is acheived on aproject specific basis. For reference,
virtually any type of roof structure andwaterproofing is suitable to have aGreen Roof including new build andretro-fit. Please contact ABG direct for
further assistance.
The U Values for Green Roofs is, at the
moment, under detailed study andcomprehensive tests have not yet beenestablished. Green Roofs are proven tohave a cooling effect in summer andwe are currently working to determine
whether they assist the insulationagainst heat loss in winter. Until the
findings are published Green Roofs stillrely on the usual insulating layer tomeet specification.
Plants/Vegetation
Plants are selected on a projectspecific basis. Plant choice shouldreflect air pollution, location, building
height, shade, weight limitations, levelsof maintenance etc. The choice is also
dependent upon what the client wantsto achieve, i.e. does it need to be green
from day one?
For intensive roofs there are fewlimitations. For extensive roofs thereare 4 main options when it comes to
vegetation & planting:
Pre-grown Mat - a vegetation mat where the
material is grown to maturity, rolled up and supplied in the form of a mat. This can be
either sedum, turf or meadow plants to
create an instant green effect.
Plug Planting - ideal for smaller projects.
This involves planting species such as
sedum, typically 20 per square metre. For a
fuller cover you can incorporate cuttings or simply increase the number of individual
sedums per square metre.
Brown roof vegetation - replicating the
existing site conditions on the roof.
Hydro seeding - the process of spraying a
specially mixed slurry comprising of water,
seed, mulch & fertiliser directly on to the substrate. It typically takes 12-18 months for
full coverage.
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Substrate
The substrate used in Green Roof projects can be designed specifically tosuit each project and this can be varied
to meet the requirements of thevegetation and surrounding ecosystem.
The substrate can range from low
nutrient site specific medium such as alimestone mix for calcareous grassesand plants, to a composted nutrientmix to support geophytes such as
snow drops or daffodils and a range of herbacious plants and other nativeperennials.
The most common mix for extensiveGreen Roofs is a free drainingformulated layer consisting of organic,
inorganic, mineral and recycledcomponents, sometimes sintered clayor slate is added to aid the absorption
of rainwater, the material is lightweightand helps minimise weight on the roof structure.
The most common mix for intensive
Green Roofs uses a denser and slowerdraining substrate. This consists of both organic and synthetic materials to
simulate a topsoil type material whichcan support a wider variety of vegetation.
Edging DetailWhilst Green Roofs are accepted as fireresistant, additional fire preventionmethods, such as a firebreak, should
be taken in to consideration at thedesign stage. The need becomesmore prevalent in the case of extensive
roofs, primarily due to their shallowlayer of substrate and general lack of irrigation.
A typical firebreak would consist of a300mm wide layer of 20-40mmrounded stone or decorative gravel.
This layer should be equal to the depthof the build up and run parallel with theperimeter of the roof.
9. Components cont.
ABG Ltd E7 Meltham Mills Road Meltham West Yorkshire UK Tel: 01484 852096 Email: [email protected]
Roofdeck
Insulation
Firebreak
300mm typical
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10. Extensive Green Roof Drainage - Finesse Roofdrain
ABG Ltd E7 Meltham Mills Road Meltham West Yorkshire UK Tel:+44(0)1484 851 562
Drainage and water storage areparticularly important components
in any Green Roof project. As amanufacturer and supplier we have
developed drainage and filter productsto suit both intensive and extensiveroofs.
Extensive Green Roofs consist of a thin
substrate growing layer. During dryspells this substrate would dry out
quickly, impacting upon the plantsthemselves.
Finesse Roofdrain is a lightweightwater storage geocomposite primarilyintended to solve this problem. In
addition to providing drainage theperforated Roofdrain core (see
adjacent picture) provides a waterreservoir for plant roots, storingbetween 4 and 20 litres per m² and inturn aiding sustained growth during dry
spells.
Finesse Roofdrain attenuates the
rainfall run off and is therefore an active
SUDS system. This ability to controlthe discharge rate is a key criteria in
overcoming planning constraints.
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As much as 95% of rainfall onundeveloped land is naturally absorbedinto the vegetated surface only 5%becomes run off. Within a catchmentarea the streams and rivers haveevolved in response to this minimaldischarge from the land. Urbanisationand development of land creates hardimpervious surfaces that absorb only5% of the rainfall, a huge 95% of therainfall becomes run off. The streamsand rivers cannot accomodate thishuge influx and the result is severeflooding and erosion.
The only viable solution botheconomically and ecologically, is toensure that the built environment has asimilar rainfall response to the natural
land. One method is to build SUDStanks below ground to store excesswater until the rainfall has abated. Theother method is to construct GreenRoofs so that the building directlyreplicates the land on which it is builtand discharge is reduced to less than5% as run off.
A Green Roof is the natural way toattenuate rainfall it can also be incertain situations the most economicalmethod in addition a Green Roof willfunction in areas where a SUDS tankwill perform poorly e.g clay,contaminated land, aquefious etc...
For a Green Roof to provide a SUDSsolution the geocomposite, waterattenuation and substrate layers arespecifically designed wih enhanced
water storage capacity. Storage
capacities approaching 100l per m2can be acheived this way. This storedwater can be released slowly or usedas grey water or irrigation for thevegetation.
A Green Roof provides ecologicalbenefits to the local flora and fauna thata SUDS tank cannot.
11. SUDS and Rainwater Attenuation
ABG Ltd E7 Meltham Mills Road Meltham West Yorkshire UK Tel: 01484 852096 Email: [email protected]
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12. Intensive Green Roof Drainage - Finesse Deckdrain
As intensive Green Roofs have a far
greater depth of soil this layer isless likely to dry out but requires gooddrainage to ensure that the roof does
not become water logged.In this instance we offer FinesseDeckdrain. This product consists of a
combination of either a 12 or 25mmthick cuspated core with a geotextilefleece bonded to the upper face.
Finesse Deckdrain provides excellentdrainage over the whole base area of the soil layer in addition to providingadditional waterproofing protection.
Please note: both Deckdrain &Roofdrain incorporate a filter fleece and
can be rolled out during installation asan all in one layer.
The deck drain product is alsoenvironmentally friendly and can be
made of 95% recycled material, therebyhelping reduce the carbon footprint.
Also in house manufacturing enables a
range of different role sizes and widthswhich reduces waste and makes theproduct very cost effective.
ABG Ltd E7 Meltham Mills Road Meltham West Yorkshire UK Tel: 01484 852096 Email: [email protected]
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ABG Ltd E7 Meltham Mills Road Meltham West Yorkshire UK Tel: 01484 852096 Email: [email protected]
Stormwater ManagementIts design works by retaining water, insome cases as much as 90%, therebysignificantly reducing storm water run
off and playing an important role inreducing the risk of flash flooding.
Added protection for thewaterproofing layerThe build up above the waterproofingmembrane is proven to greatlyincrease its life expectancy. The build
up helps reduce the impact of temperature fluctuations, therebyreducing thermal stress. Anotherbenefit of Green Roofs is that severalwaterproofing companies have realisedthat a Green Roof actually protects thewaterproofing from thermal differences
in temperature and in turn, stoppingexpansion and contraction whilst alsoprotecting the waterproofing fromharmful UV rays. This prolongs the lifeof the waterproofing and many partnerwaterproofing companies haveextended their warranties when a
Green Roof is installed.
Extracts pollutants
The vegetation & plants filter dust andpollution from the air and water thusreducing the amount of chemicals and
pollutants that reach the river networks.
Aid planning consent Although there are no regulations inplace with regards to Green Roofs,many local authorities favour proposals
that incorporate sustainable drainagesystems.
13. Benefits of Green Roofs
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ABG Ltd E7 Meltham Mills Road Meltham West Yorkshire UK Tel: 01484 852096 Email: [email protected]
Mitigating the Urban Heat
Island effectCity centres are known to have highertemperatures than surrounding rural
areas. This is due to a number of factors, many of which are linked to thespecific heat and impervious nature of
city surfaces such as concrete, tarmacand traditional membrane roofs. Thisis known as the Urban Heat IslandEffect.
Other advantagesGreen Roofs help create a living habitatfor small wildlife & a wide variety of
plant species; create more accessiblespace in densely populated areas;more aesthetically pleasing than a
traditional roof.Noise reduction
A Green Roof is also very good at
reducing low frequency sounds, anextensive Green Roof can insulate upto 40dB and an intensive Green Roof can insulate up to 50dB which can
make a noticable difference especially
near airports.
Reduced air conditioning loadGreen Roofs cool in the summer thus
reducing the energy consumption of the building and decreasing carbonemissions. This helps to reduce the
urban heat island effect.
A study in Toronto estimated that directenergy savings through city wide
greening would result in a reduction inpeak demand and result in a saving of approximately 55,000 metric tones of fossil fuels per year.
BREEAMBy improving the energy performance
of buildings and embracing GreenRoofs not only does it help to meetstandards such as the code forsustainable homes and BREEAM, it
also helps to meet planningrequirements and the revisions to PartL Building Regulations. A development
which incorporates a Green Roof can
earn up 6.2 points on an Eco Homes
score. A Green Roof also contributes tosustainability and enhances local
biodiversity. This provides a solution toenvironmental policy issues whichsaves the developer time and money.
14. Benefits of Green Roofs cont.
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ABG Ltd E7 Meltham Mills Road Meltham West Yorkshire UK Tel: 01484 852096 Email: [email protected]
15. Barriers & Myths
“Green Roofs are expensive to
maintain”Even though extensive Green Roofs arerelatively self-sustaining, they still
require some form of maintenance. ABG recommend this should be dealtwith in the form of a maintenance
contract. Maintenance for extensiveroofs will typically be required twice inthe first 12 months, then once annuallythereafter. Therefore the overall cost of
maintaining a Green Roof can berelatively minimal.
“Green Roofs cost more”
In terms of initial outlay Green Roofsare generally more expensive thanconventional roofs. However when
taking into account factors such as thewhole life cost of the building, thereduction in other infrastructure such
as stormwater tanks, and the extensionin the life of waterproofing membranesthis additional cost can be easily offset.
Until UK legislation arrives, cost will
inevitably be a determining factor as towhether the Green Roof project goesahead or it doesn't. At ABG we work
with a varied network of specialistsuppliers enabling us to provide eachcomponent of the Green Roof. As
opposed to having a 'one system fitsall' approach, our supply chain enablesus to put forward bespoke systems to
meet the needs of the client, on timeand within budget.
Please contact us for advice onsystems to fit your budget.
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ABG Ltd E7 Meltham Mills Road Meltham West Yorkshire UK Tel: 01484 852096 Email: [email protected]
“Green Roofs are susceptible to
fire” A fire is actually 20% more likely tooccur on a bitumen exposed roof. In
addition to this Sedums used on mostextensive Green Roofs are succulentswhich do not burn easily. Another
important element is to include forshingle fire breaks around theperimeter of the roof.
“A Green Roof will leak”
On the contrary, a Green Roof willactually help protect the membranefrom the weather, whilst the root barrier
will prevent any damage to thewaterproofing caused by plantintrusion.
Please ensure the waterproofing is leaktested prior to installation of the greencomponents. Contact ABG for advice
prior to installation.
16. Barriers & Myths cont.
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ABG Ltd E7 Meltham Mills Road Meltham West Yorkshire UK Tel: 01484 852096 Email: [email protected]
17. Design Considerations
There are a number of important
issues to consider when planningand designing a Green Roof.
Structural Loadings
The introduction of a Green Roof willhave loading implications for thebuilding. It is vital to consult a
structural engineer at an early stage.This will enable you to determine anyconstraints you may be under and inturn help decide which type of Green
Roof system to implement.
Example:Saturated
Type Weight (Kg/m²)
Extensive 60-150
Intensive 200-500
Compressive strength A factor which is commonlymisinterpreted is the structural
requirements for the drainage layer anddescriptions such as 1000 kPa are
sometimes mentioned.
This is significantly above the
requirements of the roof and indeedmost roofs do not need anything above150kPa. From the diagram to the right,
which is from independent test data, itshows the pressure exerted by a fullyloaded construction vehicle. As you
can see the actual loads exerted forGreen Roofs and podium decks areactually quite low.
The chart shows the compressive
strength of a 500kPa product and inparticular that a product designated as500kPa working load, actually has a
peak compressive strength of 1200kPa.This means that a 500kPa product canaccommodate high short term
construction loads and will also providelong term performance under designloads without danger of collapse.
Roofdeck
5T wheelLoad HGV
150m
Deckdrain
1200
1400
1000 m ² )
600
800
s s ( k N /
200
400 S t r e
0
0% 10% 20% 30% 40% 50% 0%0% 10% 20% 30% 40%
Strain
Compression of Deckdrain 1250S drainage core
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ABG Ltd E7 Meltham Mills Road Meltham West Yorkshire UK Tel: 01484 852096 Email: [email protected]
Access & Maintenance
Even extensive roofs need occasionalmaintenance. Provisions must bemade for this. The BRITISH STANDARDS
INSTITUTION state that all new buildsmust provide access to the roof area toenable a minimum of 2 inspections per
year. The installation of a Green Roof does not change this, but if there is noedge protection on the building, healthand safety regulations require anyone
within 2m of the edge to wear a safetyharness.
Drainage & Water Retention
Drainage and water retention are keyelements to consider when designing aGreen Roof. The specific type is
entirely dependent upon the proposedlandscaping element. Ensuringadequate water retention requirements
are met will aid the long term survivalof the vegetation whilst adequatedrainage provisions will prevent poolingand in turn prevent the plants
becoming saturated.
Please note: Irrigation will be required
immediately after installation. Forfurther information please contact ABGdirect.
Geographical LocationGeographical location and orientationare also an important part of designing
the roof. Which area of the country andthe amount of average rainfall in thatarea determines the type of uses andneeds for the Green Roof. Biodiversity
and drainage are then designed intothe roof from these requirements. Thedirection in which the roof faces and
amount of sunlight the roof receiveshelps to determine the types of vegetation for a sucessfull roof.
18. Design Considerations cont.
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ABG Ltd E7 Meltham Mills Road Meltham West Yorkshire UK Tel: 01484 852096 Email: [email protected]
19. The Future
As the world begins to understandclimate change is happening and
something needs to be done theawareness and understanding of Green
Roofs is increasing. This is helped byevents including "World Green Roof Congress", the development of GreenRoof organisations such as "Living
Roofs" and research centres likeSheffield University who are developingGreen Roof exhibition centres and
forums.
Unlike our counterparts in Canada, America and mainland Europe theGreen Roof policy is not part of our
legislation yet but it is coming!
New reports that have recently been
released have announced that by 2015there has to be a zero storm water runoff rate for all new buildings.
There are Local authorities and
developers in the UK who recognisethe importance of the Green Roof
system in the fight against climate
change and the need for sustainableurban drainage systems, they are
proposing Eco friendly plans to putGreen Roof into policy.
Sheffield development framework (partof the Sheffield city council) havealready consulted on "Emergingoptions" for new policies and are now
consulting on preferred options.
Option 1 Green Roofs will be required
only on medium or large developmentswithin 100mtrs of the green belt, greennetwork, waterways, parks and openspaces greater than 1 hectare.
(Medium or large = Non residential developments
over1000sq meters and residential over 10 dwellings.)
Option 2 Green Roofs will be required
on all medium and large developments.
Option 3 Green Roofs will be requiredon all developments.
As all parties ranging from
manufacturers and suppliers to local
authorities and developers continue to
work in conjunction with one another,the future expansion of Green Roofs
within the UK is inevitable.
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ABG Ltd E7 Meltham Mills Road Meltham West Yorkshire UK Tel: 01484 852096 Email: [email protected]
Overall Green Roofs offer a wide
range of social, economic andenvironmental benefits. These rangefrom significant ecological issues, such
as helping to mitigate climate change,whole-life cost benefits or somethingeven simpler, such as "It looks nicer
than a traditional roof". Whatever thekey influences are, it looks like GreenRoofs within the UK are set for asustained period of growth.
Going forward Green Roofs will not justlook to attenuate water but to reduceflooding and erosion. These will
provide an alternative beneficialsolution to SUDS tanks.
The purpose of this booklet is to help
give you an overview of key factors totake in to account when proposing,designing or specifying a Green Roof.
Seeking advice from the experts isessential to the projects success.Therefore next time you are thinking of incorporating a Green Roof system in
to a new or existing development don't
hesitate to contact ABG direct and letus assist you through every stage of the process from design through to
installation.
20. Summary
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ABG Ltd E7 Meltham Mills Road Meltham West Yorkshire UK Tel: 01484 852096 Email: [email protected]
Think Green Roofs...
...Think ABG
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ABG Ltd E7 Meltham Mills Road Meltham West Yorkshire UK Tel: 01484 852096 Email: [email protected]
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