A wide range of accessories such as fixing clips, expansion joints, patination oil, restorers and lead sealants, underlays and wood cored rolls, oxy-turbo set, tools, etc.
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Breather Membrane in roll sizes of 50 x 1mt and 50 x 1.5mt include BBA for both warm and cold applications. Non breather replaces the traditional 1F by offering a lighter, stronger product that will not rot.
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Expanded polystyrene boards are formed by a steam heated process which expands the beads of polystyrene and fuses them into a slab. Boards are available in various grades and are available with a pre-felted upper surface factory bonded fibreboard or Perlite board for use in roofing applications which has the dual function of shielding the expanded polystyrene from hot bitumen and asphalt and absorbing the thermal movement sufficiently to permit a fully bonded built-up roofing system. Expanded polystyrene boards exhibit large thermal movement and are heat sensitive. The boards cannot tolerate the temperatures which arise from the direct application of hot bitumen or asphalt and indirect laying techniques have to be adopted by applying coat hot bitumen to the substrate and allowing it to cool to a tacky condition before the expanded polystyrene is laid or a colds applied adhesive is used. The boards are available as a constant thickness or tapered to provide falls.
Allowing the use of the roof area, environmentally friendly, low maintenance, improved thermal performance and rainwater management, reduction in sound transmission and improvement in air quality. With visually attractive foliage it provides habitat for wild life particularly in city centres.
What are green roofs?
A green or ‘living’ roof is essentially the growing of plants on our rooftops. The insulative properties of soil and plants have been utilised by humans for thousands of years, cooling buildings in Africa and helping to retain heat in traditional buildings of Northern Europe and Scandinavia. Modern green roof systems combine a series of functioning layers which recreate growing conditions across the roof. Green roofs can be anything from a thin growing layer of sedums and mosses to plants, shrubs and water features. They are installed on top of conventional roofs. Properly designed, they are stable, living ecosystems that replicate many of the processes found in nature.
What are the major advantages of green roofs?
Green roofs provide many ecological and aesthetic benefits, including:
• Controlling water runoff, erosion and pollution,
• Improving water quality,
• Mitigating urban heat-island effects, cooling and cleaning the air,
• More than doubling the service life of the roof,
• Conserving energy,
• Reducing sound reflection and transmission,
• Creating wildlife habitat, and
• Improving the aesthetic environment in both work and home settings.
What are the most important factors in designing a green roof?
• Climate, especially temperature and rainfall patterns
• Strength of the supporting structure
• Size, slope, height, and direction of the roof
• Type of underlying waterproofing
• Drainage elements, such as drains, scuppers, and drainage conduits
• Accessibility and intended use
• Visibility, fit with architecture, and owner’s aesthetic preferences
• Fit with other ‘green’ systems, such as solar panels
• Costs of materials and labour
What is the difference between an ‘extensive’, ‘intensive’ green or ‘brown’ roof?
Extensive lightweight, low cost and maintenance. Normally less than 6 inches deep, and, depending on depth, may support a range of plants, such as Sedums (low-growing succulents), herbs, meadow grasses, and perennials.
Intensive deeper substrate on load bearing applications. Multifunctional systems can sustain complex landscapes, including small trees and even small ornamental ponds and fountains.
Bio-diverse or Brown are like substrate based roofs, but roughly translated they recreates the surrounding wildlife habitats, can use recycled materials and are generally left to colonise naturally or seeded with an animal wildflower mix.
How much does a green roof weigh?
Green roofs vary greatly in weight, depending on their depth and the materials used. The important measurement is ‘wet’ weight — fully-saturated fabrics and plants. Weights are about 60-150kg square metre. Any calculations must take into account the weight of water held in the soil and any snow loading.
How does a green roof affect the conventional roof below it?
One of most important benefits of green roofs is protection for the underlying waterproofing membrane and can be expected to double or triple the life of the underlying conventional roof by protecting from human activity and wind-blown debris; shielding from UV radiation; and buffering temperature extremes, thereby minimizing damage from daily expansion and contraction.
The ‘conventional’ approach to green roof design focuses on covering 100% of the waterproofing materials. In particular, conventional green roof detailing focuses on covering and protecting the most vulnerable parts of the roofing system: its flashings, penetrations, terminations and drains. One example is the use of enclosed drain access chambers to protect drains and scuppers and to eliminate the potential for clogging by blowing trash or vegetation. Green roofs, provide 100% protection by incorporating vegetated or stone margins, drain access chambers, etc.
What kind of waterproofing do I need?
Many types of waterproofing are compatible with green roofs. Bituminous membranes, single ply and liquid coatings are the most common. Many of these installations have now been in place for over 30 years and continue to perform as designed. PVC, EPDM and thermal polyolefin (TPO) are, in most cases, inherently root-resistant; other common waterproofing materials require a root barrier between the waterproofing materials and the vegetated cover.
How do Green Roofs affect the building they are on?
Green Roofs reduce the temperature inside the building they are on during increasingly hot summer months. The UK currently spend more money (uses more energy) cooling buildings than heating them in winter. Green Roofs reduce the need for air conditioning in the summer and as a result reduce CO2 emissions and keep the building cool.
How do Green Roofs affect the quality of life for people?
Green Roofs contribute to a greener urban environment and quality of life for communities in high density areas.
How do Green Roofs affect wildlife?
New developments lead to a loss of habitats. Green Roofs can contribute to biodiversity and address local biodiversity action plans. In particular they have been to favour many rare invertebrates found on brown field sites, as well as ground nesting birds such as skylarks.
Are leaks under a conventional green roof a problem?
Leaks in the waterproofing layer are less likely when it is protected from the elements by a green roof. If a leak does occur, it can readily be located through new electronic technology which can rapidly and accurately pinpoint even minute holes. These systems are more reliable than the older testing method and can even be used on steeply-sloped surfaces. Repairs to the waterproofing are quick, and disturbance of the green roof is minimal.
Is attaching all elements of the green roof to the underlying structure important?
Plant roots bind the layers of media and fabrics to create a unified cover, and the plants themselves create enough surface wind turbulence to foil potential uplift. If your green roof will be located in an unusually high wind area, such as a high rise building or coastal area you may need to use appropriate ballasts which should withstand winds of up to 94 mph using concealed ballasts.
How steeply pitched can the roof be?
The maximum slope recommended for conventional green roofs is 30 degrees, pitch. A variety of methods utilizing meshes, slope stabilization panels, cribbing, or battens can be used to secure the green roof and prevent media shifting and erosion.
Roofs with pitches greater than 30 degrees can be greened; however, special techniques are required.
Do I need to consult a Structural Engineer?
It is always advisable to contact a Structural Engineer, however if you have discussed the design with Building Control and they are satisfied that the nature of the work does not require additional strengthening it is your choice whether to ask structural engineer.
In what climates do green roofs work?
Green roofs have been built most widely in temperate climates, but special techniques allow them to thrive in semi-arid, tropical, and even windy coastal areas and have been installed from hot, moist to the cold, windy locations.
Is irrigation required? If so, what kind?
With thoughtful planning irrigation is rarely necessary. When irrigation is required, the water should be delivered deep under the surface—where the roots will seek it and it will not be lost to evaporation. Surface irrigation systems are wasteful and require more maintenance than subsurface irrigation methods.
How do Green Roofs affect water drainage from the roof?
Research from around the world indicates that Green Roofs reduce annual run-off roofs by at least 50% and more usually by 60-70%, contributing to urban drainage and flood alleviation schemes. Moreover, the rate of release following heavy rainfall is slowed, reducing the problems associated with storm surges. With an increasing need for developments to have limited water run off the Environment Agency now highlights the use of Green Roofs in their May 2003 publication ‘Sustainable Drainage Systems’ and introduction.
What kinds of plants should be used on a green roof?
In areas where frost occurs at least half of the plants installed on an extensive green roof should be varieties of Sedum. In colder climates grass-dominated covers are recommended. Reliable tropical plant lists are not recommended.
Many other plants can be incorporated to provide habitat value or visual interest. Appropriate auxiliary plants will vary by region, but generally, the deeper the green roof, the more complex the plant community that can be sustained. They range from Sedum and herbs on the thinnest systems, to meadow grasses and perennials on mid-weight roofs, to turf and small trees on the deep, ‘intensive’ roofs. The selections will depend on many factors: depth of growing media, seasonal temperature ranges, average rainfall, and the aesthetic preferences of the owner.
Where do I buy seeds or plants to build my green roof?
We can either supply plants or seed or advise you where to buy them.
Are any green roof plants invasive non-natives that could be spread by wind?
The only Sedum that might be considered invasive is Sedum sarmentosum also known as Star Sedum, Gold Moss, Stringy Stonecrop, or Graveyard Moss. It has green spearhead-shaped leaves, lemon yellow flowers, and long tendrils and is not recommended.
How are green roof plants started?
There are several methods for starting green roof plantings. From April through October, Sedums may be established from fresh cuttings. Broadcast on the growing media, these cuttings will quickly form roots and affix themselves. Alternatively, Sedums may be started in May-June or September-October from 72-cell plugs, planted a foot apart. Perennials can be seeded, except during the summer months. A bio-or photo-degradable wind barrier fabric or hydro mulch is required while the plants are being established.
How long until the roof will be fully covered?
Generally, a green roof that is planted correctly will reach maturity in two growing seasons, or less. Occasionally, reduced sun or rain may slow the process. If more rapid maturity is desired, pre-grown Sedum mats, can be used.
Is there a danger of dry plants catching and spreading fire?
Not if the green roof is designed correctly. Green roofs actually have a better fire rating than conventional roofs because the mineral media layers cannot burn. The extensive use of Sedums and gravel borders and breaks also protect against fire
What effect will the winter freeze and thaw cycles have on the roof?
Not all green roofs are resistant to freeze and thaw cycles.
Is there erosion in the winter when the vegetation dies back?
The design of a green roof system should include a significant percentage of non-deciduous plants, so that the mature cover is never 0bare of foliage and the potential for erosion is minimized. The risk for erosion is greatest just after the initial planting.
Can I plant a flower or vegetable garden on my roof?
Generally, green roof systems are not deep enough for growing vegetables and the tools of traditional gardening would damage the green roof and the underlying waterproofing. However, incorporating container gardens or modular elements can accommodate an owner’s horticultural or agricultural desires.
Will I be able to walk on my green roof? Can it be used for recreation?
If the roof is accessible from the building and the roof will support the weight, decks, patios, and walkway pavers can be integrated into the design of the green roof. Among the available plant covers, only turf grass will stand up to regular foot traffic. Turf green roofs will require a minimum of 6 – 9 inches of media depth and irrigation is mandatory (i.e., an intensive green roof). As an alternative, stepping stones or walkways can be used to provide access through more fragile extensive green roofs.
What kind of maintenance is required?
Generally, after the plants have become established, most extensive green roofs only need weeding and occasional infill transplanting. Maintenance visits should be timed to intercept any weeds before they go to seed and should be sufficient to maintain the health of the plants and protect the underlying roofing materials.
Can green roofs be combined with other green features?
Green roofs can be designed in conjunction with solar panels and in combination with other ‘low-impact’ development measures, such as infiltration beds, rain gardens, bio-retention systems, cisterns and rain barrels.
Can recycled materials be used in constructing green roofs?
Reducing the use of virgin materials is an important goal if the green roof industry is to be sustainable in the long run.
How much does a green roof cost?
Cost per square foot depends on many factors: the size and slope of the roof, depth and complexity of the system, height and accessibility from the ground, cost of labour, and need for specialised elements, such as drains, railings, pavers, slope stabilization measures, etc.
What financial benefits do green roofs provide?
Years of experience throughout the world have shown that a green roof can be expected to outlast a comparable roof without a green roof by a factor of at least two, and often three, many experts expect that these installations will last 50 years and longer before they require significant repair or replacement. For a building owner with a long-term investment in the roofing system, this benefit factor goes a long-way toward paying back the initial investment in a green roof.
Will a green roof save energy?
Yes, although not due to insulation or “r-factors.” A green roof acts as a heat sink, slowly absorbing and holding energy from sunlight and releasing it when the ambient air cools. In this way, it acts as a heat “storage battery” and reduces the heating and cooling demands within the building. Energy savings will be greatest in low buildings, due to the high ratio of roof area to the total of exposed building skin.
Does a Green Roof require planning permission?
It is always advisable to contact your local planning department and explain what you are aiming to do, especially if it is on a permanent structure such as an office, dwelling or garage. They will advise you on what your next steps should be, they will also ask you to speak to Building Control who will be interested in the technical nature of the installation i.e. building loading etc.
IS THERE ANYTHING I SHOULD AVOID IN BUILDING A GREEN ROOF?
To build and maintain a successful green roof, there are several design and installation problems to avoid:
Avoid any design that is not properly drained.
Inadequate drainage can result in:
(1) Dead weight that the roof may not be able to sustain;
(2) Plant mortality; and
(3) Degeneration of the planting media
Avoid using herbicides to prevent root penetration of the waterproofing.
Herbicides will eventually leach out of materials, escaping into the environment and diminishing the root-inhibiting function of the root-barrier. When supplemental root-barriers are required, we recommend using thermoplastic membrane.
Avoid using surface irrigation, if at all possible.
Surface drip and spray systems are expensive to maintain, do not deliver water efficiently to the roots, where it is most needed — and waste enormous amounts of water through evaporation. Also, on surface-irrigated green roofs plant roots tend to develop nearer the surface. This makes the covers increasingly dependent on irrigation and vulnerable to lapses in the watering schedule.
Avoid providers who know only one tune.
No one system is suited to all roofs—there are too many variations in pitch, drainage, climate, and exposure, to name but a few engineering considerations. ‘One-size-fits-all’ serves the aims of the manufacturer, not the needs of the consumer.
Finally, avoid false economies.
Your green roof is a long-range investment. The highest return will come from thoughtful, responsive design engineering and stringent standards of installation and maintenance, giving you a trouble-free green roof for years to come.
What are the different types of green roofs and specification?
| Green Roofs
A green roof is broadly speaking one with plants growing on its surface. This could range from a spontaneously occurring moss and lichen covered roof to a full-scale roof garden that includes trees, shrubs and hard landscaping features. Green roofs have been fundamentally divided into two categories, intensive, extensive and brown or bio diverse. Intensive green roofs are roof gardens that can provide space for people and recreation. They require the same management of a ground level garden and are usually based upon a thick soil or substrate layer and require artificial irrigation. Preferred plants are selected and the roof conditions created to support them. They are heavy systems and can have major structural implications for the building. Extensive green roofs are not usually recreational (although the two systems can be integrated). They have low maintenance requirements and do not usually require artificial irrigation. Planting styles are usually naturalistic with the objective of establishing a self-sustaining plant community on the roof and plants are selected that will succeed with only minimum of alterations to the normal roof conditions. They are based on a layer of growing medium and are lightweight systems with minimal structural implications for the building. The main reasons for installing an extensive green roof are visual appeal, assist dispersal of rainwater, reducing the environmental impact of the building, creating habitat for native flora and fauna and wildlife, improve the insulation, sound of the building performance. The essential benefits of extensive green roofs are the following: Visually attractive with a range of flower and foliage effects. Low maintenance with little or no artificial irrigation requirement. Assist the dispersal of rainwater Improved building thermal performance both in winter and summer. Reduction in sound transmission through the roof. Improvement of air quality through removal of carbon dioxide, release of oxygen and water vapour, deposition of particulate pollutants, and absorption of organic volatiles. Reduction of the urban heat island effect Provision of wildlife habitat Green roofing specification |
ans extensive green roof module (vegetation carrier) with sedum planting
size 1m x 500mm x 50mm depth
132 water retaining cuplets per m2, incorporating drainage holes
adjoining modules overlap by 100mm, and interlock into overlapping cuplets
compressive strength of 150 knm2
bio-filter blanket fixed to ans vegetation carrier, including moulding into water retention cuplet
water holding capacity of 64kg per m2
ans green roof media, consisting of peat free compost, recycled sand, leca, pea shingle, and other drainage substances can be added
ans extensive roof media spread to a depth of 60/70mm, approximately 50kg per m2
supplied with established sedum planting, between 6 – 8 varieties, into the roof media
Brown or Bio-diverse roof build up
Typically, the build-up of a bio-diverse roof will be similar to that of an extensive flat roof. However instead of planting with sedum or turf blanket, a variety of plants and growing mediums, aggregates, timber, stones etc. will usually be used to blend with the local area to achieve the relevant biodiversity.
Maximising biodiversity
To maximise biodiversity, a wide selection of locally sourced growing mediums will normally be distributed around the roof surface. In many cases, these are either left alone to allow the germination of wind-blown seeds, or alternatively, seeds collected from the local area are scattered over the roof area. Over time an ecosystem of plants and animals will develop on the roof similar to the local environment.
Where structurally possible it is considered beneficial to vary the depth of the soil/rubble etc. This allows the roof to provide potential habitat for as wide a range of species as possible. The easiest way of achieving such depth-variation is often to place mounds of soil/aggregate directly over support pillars. If there are any doubts about the load bearing properties of the building a structural engineer should be consulted before deciding on the landscaping of the bio diverse roof to ensure that the underlying structure can support both the overall weight of the roof and any high localised loadings caused by mounds of soil/aggregate.
Designing for a specific species objective
Where a habitat is being designed to support a specific species, conservationists will normally be consulted to assist in devising a roof-top habitat that will attract and support the target species. at
| brown roofing specification |
ans extensive brown roof (vegetation carrier module) with wild flower planting
size 1m x 500mm x 50mm or 1m x 1m x 50mm depth
132 water retaining cuplets per m2, incorporating drainage holes
adjoining modules overlap by 100mm, and interlock into overlapping cuplets
compressive strength of 150 knm2
bio-filter blanket fixed to ans vegetation carrier, including moulding into water retention cuplet
water holding capacity of 64kg per m2
ans brown roof media, consisting of local stone, recycled green waste, recycled sand, dead root outcrops
ans brown roof media spread to a depth of 70/80mm, approximately 58kg per m2
media raked over and over sown with wild flower seeds, or plug planting, both indigenous to local areas
it is recommended that ans extensive brown roof installation is laid onto a root barrier membrane
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AlumTech is a radiant insulation for application on both flat and pich roofs. It is made of two layers of air bubble polythylene, wedge-welded for a width of 15mm and covered by a film of low emission aluminium on both sides. The materials used to make AlumTech are absolutely safe, non-toxic and non-harmful.
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A wide range of slate from various parts of the world are produced to the very highest standard and selected for quality, consistency and cost effectiveness. The quarries are from Spain, Brazil, North America, China and the UK.
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High density polyethylene nodular sheets collect water and channels it away from the surface, protects the membrane from abrasion or puncture damage due to infill, has high tear resistance and allows ventilation to walls, tunnels, buildings, garden areas etc.
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