The roof is a forgotten element
on most buildings - unnecessarily. Designed and
built as a multi-functional element, roofs can
be environmentally friendly and aesthetically
Click here to
see the green roof gallery
This state-of-the-art roofing-landscape assembly
provides an Owner with many new benefits:
- Create Aesthetic Appeal of The Roof
- Increased Property Values
- Increased Usable
- Reduced Energy Costs
- Controlled Storm Water
- Tax Benefits In Some Areas
- Conversion of Carbon
Dioxide to Oxygen, Improving Air Quality
Airborne Toxins Through Photosynthesis
- Reduced Heat Island Effect
- Prolonged Roof
- Reduced Debris Sent To Landfills
and Recyclable Materials In Most Components
Green Roof— Roofscape
can turn unused roof space into a park-like garden
setting with a keen sensitivity to environmental
The Green Roof—Roofscape is designed around
inter-dependent components which function as
a natural planting habitat. The otherwise "lost" roof
space can be used to create a public or private
open space, offering serenity, balance and harmony.
Green Roof - Roofscape Components
The membrane is the most critical element of
the assembly. Without a tough, long-life, watertight
membrane the entire concept is undermined.
The time-proven Barrett RAM Tough 250 membrane
- A fluid-applied SBS Modified bitumen,
reinforced with spunbond polyester fabric for
extra toughness and redundancy.
- Aggressive full
adhesion to the structural substrate preventing
water migration between the membrane and the
deck in the event the membrane is damaged.
monolithic waterproofing membrane, without
seams or joints, which can withstand constant
water immersion and hydrostatic pressure.
- Longterm physical stability in an
enviorment of water, fertilizers, chlorides,
and mild acids.
- Reliable and redundant detailing at
all penetrations and perimeters.
- High abuse resistance
of the membrane as measured by the membrane's
toughness and tenacity
- Exceptional self-healing properties
in warm tempertures.
- Quality control program from design
through project completion.
- Over two decades of proven performance.
Green Roof— Roofscape designs
incorporate long-term protection from root growth
penetrating the membrane. The thickness and the
construction of the root barrier and protection
layer will vary depending on the vegetation plan
and other design considerations. Several types
of root barriers are available.
Drainage,Water Retention & Aeration
The alternating balance between drainage, retention
of a supplementary water supply for plantings,
and aeration, can be provided with RAM drain
mats. RAM drain mats are manufactured
with small integral reservoirs providing for
improved plant hydration while simultaneously
allowing drainage and air flow. Ram Roofscape
Drainage mediums have a heavy polyester mat on
the bottom for additional protection of the membrane.
The top polyester geotextile fabric acts as a
filter to prevent soil migration into the drainage
For plants less than 24 inches tall.
Water flow—12 gallons/min./12 in.
Water Retention —10 cu. in./SF
Ram-Drain Roofscape 2451
For plants over 24 in. tall
Water Flow —100 gal/min./ 12 in.
Water Retention—14 cu. in. /SF
For drying insulation and protection.
help maintain a sustainable environment for
vegetation, water is controlled through a combination
of aeration, drainage and retention mediums.
Soil depth and vegetation design will dictate
the appropriate control materials.
Insulation is typically a high density extruded polystyrene. It is installed
over the membrane and root barrier. The weight of the soil overburden will dictate
compressive strength-requirements of the insulation.
Soil specifications are determined by the Landscape Architect. Many variables
affect the choice of the proper soil mix and these variables are evaluated for
the specifics of each project.
Soils are classified as mineral, organic, synthetic and fertile topsoil. They
are usually blended together in different ratios. Soil considerations include:
- Vegetation Requirements
and Nutrient Retention
- Drainage Design
- Porosity and Compaction
Restrictions on Structure
- Resistance to Fire
- Structure for Plant
Plant specifications are determined by the landscape
architect or a horticulturist. Designs are
classified as High Profile and Low Profile.
Low Profile planting
systems are generally composed of plants
less than 24 inches tall. A single layer
of root protection is usually required.
Low profile designs typically include grasses,
herbs, wild flowers and sedums. Low profile
systems are considered low maintenance.
Click to download Low Profile Specifications
High Profile plantings, in
excess of 24 inches high, or with aggressive
root systems utilize multiple layers of root
protection. High profile systems include shrubbery,
decorative trees,and sod. High profile systems
are generally high maintenance designs.
to download High Profile Specifications
- Root System Anchorage
- Reactivity to Direct Sunlight
- Drought and Wind Resistance
- Maintenance Requirements
- Local Climatic Condition
- Wildlife Habitat
It is a standard roofing industry recommendation
that all roofs have an ongoing maintenance
program. Green Roof— Roofscapes also
require a programmed cycle of care and maintenance
appropriate for the planting design.
All Barrett membranes are UL Class A and many
are FM Class I-90 approved, however, UL and FM
do not yet address Green Roof— Roofscape
designs. Ballast weights are easily adjusted
to comply with industry standards. Wind erosion
of the soil can be addressed with a number of
design features including geotextile erosion
control mats. Newly planted shrubbery and ornamental
trees should be anchored to prevent uprooting
Green Roof — Roofscapes that are properly
maintained are generally considered to be acceptably
fire resistant. Consult local code officials.
Green Roof — Roofscapes are almost always
installed over concrete decks which produces a
high degree of interior fire protection.
Most Green Roof— Roofscape
systems are irrigated with sprinklers, providing
additional fire protection. Nonirrigated systems
require firebreaks or firebarrier every one hundred
feet, in each direction. Additional vegetation-free
zones are required at all roof top openings for
additional fire safety.
should be manually watered in periods of drought
to reduce fire risks. High organic content soil
is not recommended for fire-safety reasons.
Flashing conditions and perimeters are designed
without soil cover or plantings in a 24 to
36 inch wide border path which is typically
filled with gravel ballast or precast concrete
pavers set on pedestals. Flashing heights must
rise above the highest possible expected waterline,
in no event less than 8 inches above the membrane.
Drains are kept free of plantings and designed
with inspection and cleanout boxes. When soil depths
exceed six inches, planter drains are utilized
and installed in accordance with manufacturer’s
- If irrigation systems are not installed
as part of the system, access to a water source
must be provided.
- Plantings and soil mix are
chosen and designed by the Landscape Architect.
loads must be carefully evaluated by a structural
Engineer early in the design phase. Deadloads
can range from 21psf to over 100psf. For slopes
in excess of 3:12 consult Barrett Tech Services.
Roofscape Deadload Design Weights Are:
Membrane, root barrier, protection and insulation
Drainage - water retention 1.5 lbs
Soil, 2.5 inches of 1/3 organic, 2/3 mineral 14 lbs
Sedum plantings 1 lb
Roofscape total 21 lbs/ft2
Concrete pavers on pedestals 21 lbs/ft2
Gravel ballast 15-20 lbs/ft2
Information compliments of Barrett Roofing 1.800.647.0100