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Principles of Designing Plaza Waterproofing Systems

May 15, 2008

The design of plazas over occupied
spaces must create a system that waterproofs
and insulates the structural building
deck while supporting pedestrian and/or
vehicular traffic and landscaping elements
(Figures 1A and 1B). Their design entails
multiple layers, including a waterproofing
membrane, protection layer, drainage
course, insulation, and a wearing surface.
Earlier plaza designs did not incorporate
a drainage layer within the system
components. As a result, water that was
trapped between the membrane and wearing
surface caused deterioration from
freeze/thaw cycling or saturation. Since
publication of Charles Parise’s seminal
paper in 1981, the accepted ASTM and
industry standard requires the incorporation
of a drainage course. The system must
allow for the flow of water from the plaza
wearing surface through the various components
to the drains and sides.
There are two basic categories of overburden
on plazas over occupied spaces:
• Hardscaping with wearing surfaces,
• Landscaping or softscaping with
plantings, fountains, etc.
Systems can be further divided into categories
where the membrane is either
accessible or inaccessible.
Accessible systems are those in which
Figures 1A and 1B – Plaza with landscaping elements.
J A N U A RY 2008 I N T E R FA C E • 5
the wearing course is removable. Pavers that are installed on
insulation, pedestals, or sand beds are classified as accessible
systems. Landscaping or planting is also considered to be an
accessible system.
Inaccessible plaza systems are those in which the membrane
is covered with a concrete protection slab or where the
wearing surface units are installed in a solid, mortar-setting
bed. Fountains and most vehicular wearing surfaces fall into
this category. These systems require demolition of the concrete
protection slab or solidly grouted units for access to the
A waterproofed plaza system that includes a separate
wearing course contains some or all of the following components
(Figure 2):
• Structural deck,
• Membrane,
• Protection board or protection membrane,
• Drainage layer or course,
• Thermal insulation,
• Concrete protection slab (optional),
• Flashing, or
• Wearing surface.
An earth-covered system comprises similar components,
with the exception of the wearing surface, where the earth fulfills
the role of overburden (Figures 3A and 3B).
There are three ASTM International Standards that cover
waterproofing under hardscaping (nonplant items in a landscape):
• C981 – Standard Guide for Design of Built-Up Bituminous
Membrane Waterproofing Systems for Building
• C898 – Standard Guide for Use of High-Solids Content,
Cold, Liquid-Applied Elastomeric Waterproofing Membrane
with Separate Wearing Course, and
• C1127 – Standard Guide for Use of High-Solids Content,
Cold, Liquid-Applied Elastomeric Waterproofing Membrane
with an Integral Wearing Course.
Figure 2 – Basic components of membrane waterproofing
over a framed structural slab. (Courtesy of ASTM
Figures 3A and 3B – Basic components of membrane
waterproofing under earth.
6 • IN T E R FA C E J A N U A RY 2008
Designers are advised to consult these
standards when designing waterproofed
plaza decks because they constitute the
current body of knowledge on the subject.
A structural plaza deck typically consists
of reinforced concrete slabs, concrete
topping over precast units, posttensioned
slabs, or composite concrete and steel decking.
Reinforced structural concrete slabs
are the most common and consist of framed
or flat slabs. However, monolithic concrete
slabs make a better substrate for waterproofing.
Joints between precast units and at
their ends may not be in the same plane,
and therefore require a concrete topping to
even out lippage and to cover lifting rings
and welded plates. However, the topping is
prone to cracking along joints and, in particular,
at the end joints, which may rotate
between precast elements at supporting
Posttensioned slabs offer better control
of deflection and cracking within the plaza
deck. However, careful analysis of the deck
deflection pattern and posttensioning design
is critical to achieve proper slope to
drain after the plaza overburden has been
Composite decking comprising concrete
on steel centering is more commonly used
for terraces at higher floor levels than for
plaza design at or near grade level.
Provisions for venting moisture from the
concrete must be made if a liquid membrane
is applied to the concrete surface.
This is typically achieved by using a slotted
steel deck or additional curing time, which
can be reduced by a low cement-to-water
Whichever structural system is selected,
the waterproofing designer should assure
himself that the structural engineer is
informed as to the need for positive slope to
drain. These discussions should include
coordination among the waterproofing
designer, landscape architect, and structural
engineer to assure adequate load-bearing
capacity and slab slope.
Membranes for waterproofed deck systems
• Conventional built-up bituminous,
• Multiple-ply modified bitumen
• Single-ply sheets, and
• Liquid- or fluid-applied elastomers.
A built-up bituminous membrane consists
of alternating multiple plies of saturated
felts between applications of bitumen
applied onsite (Figure 4). The plies include
organic felt, glass mats or fabrics, and polyester
mats or fabrics as reinforcement. The
bitumen can be asphalt or coal-tar pitch.
The bitumen of choice for waterproofing is
coal-tar pitch (ASTM D-450, Type I or II)
because of its self-healing properties.
Organic felts are preferred over glass.
Asphalt (ASTM D-449) has greater water
absorption than coal-tar pitch and is not
The felt plies can be shingled or phased
(ply on ply). In a phased application, moisture
that penetrates through a lap leads
only to the next ply and not through the
entire membrane.
Except for tarred felts, membranes constructed
of organic felt have not performed
well when exposed to standing water. Glassfiber
felts are less absorbent than organic
felt, but tend to float or sink in coal tar
pitch. Roofers familiar with application of
pitch and the product itself are increasingly
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Modified bitumen sheets are made of
asphalt modified with polymers to improve
the sheets’ flexibility and elasticity and the
cohesive strength of the bitumen. Some are
self-adhering sheets, laminated to a highdensity,
polyethylene backing, and are often
called “peel-and-stick” or rubberized
asphalt (Figure 5). The
sheets can be applied
as single- or multipleply
membrane systems.
They must be protected
from ultraviolet
exposure within a few
weeks of application.
Modified bitumen
sheets used for roofing
do not perform as
well when used for
waterproofing membranes
because of the
potential for wicking
of the reinforcing at
end laps. These systems
are fully adhered to
the concrete substrate and
are sensitive to site conditions,
moisture, and deck
surface quality.
Single-ply sheets include
EPDM, butyl rubber,
KEE, and PVC. Butyl rubber
sheets have an advantage
over EPDM sheets
because of their lower moisture
absorption. This benefit
is more important for a
waterproofing membrane
than EPDM’s greater resistance
to ultraviolet exposure.
PVC sheets offer
improved puncture resistance
and heat-welded
These sheets are either
fully adhered or loose laid.
When loose laid, they
should be compartmentalized
by adhering the sheet
in a 3-m (10-ft) grid. This
forms compartments that
confine water migration if a
leak occurs and also helps
facilitate leak detection
(Figure 6).
Liquid-applied membranes
include hot and
• Polymer-modified asphalt,
• Single-blown asphalt,
• Coal-tar modified urethane,
• Two-component urethanes,
• Aliphatic polyurethanes,
• Reinforced liquid polyester,
• Two-component synthetic rubber,
Figure 4 – Application of a coal-tar pitch waterproofing
Figure 5 – Application of self-adhering modified bitumen
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• Polymer-modified asphaltic emulsion.
Proper performance of solvated or emulsion-
type membrane systems requires that
they contain a minimum of 65 percent
solids to reduce pinholing. Problems associated
with reflective cracking from the deck
below can be addressed by proper dry mil
thickness of the membrane (which is normally
a minimum 60 mils) and by reinforcing.
The advantage of adhered membrane
systems is the localization of leaks. A disadvantage
is the need for rigorous surface
preparation of the substrate, which must be
dry, with a lightly broomed texture, and
dust free. Cracks must be detailed. Liquidapplied
membranes should
never be used to fill or level
surface irregularities.
Moisture is the adversary
of these systems. It causes
urethanes to foam and hotapplied
systems to froth. Dust
can cause pinholing or
entrained air bubbles in the
coating film (Figure 7).
Unsuitable curing agents
such as water glass can
inhibit adhesion.
Hot-applied liquid systems
are often reinforced with
polyester or woven glass
(Figure 8). This process requires
two applications,
which minimizes coincident
pinholing and thin spots in
the membrane.
Cold-applied liquid membranes
are applied over a concrete substrate
by spray, squeegee, roller, brush,
trowel, or other method acceptable to the
membrane manufacturer (Figure 9).
Manufacturers claim that these products
are sufficiently elastic to bridge cracks that
occur in the concrete after the coating is in
place. Reflected cracking is reduced by
increased thickness.
The reinforced liquid polyester systems
require exposure to ultraviolet light to cure.
PMMA (polymethyl methacrylate) cures
from contact with moisture in the air.
ASTM International Standard C-836,
which was first published
in 1976, is a nonproprietary
specification that describes
the required properties and test
methods for cold-applied, elastomeric-type
waterproofing membranes for both one- and
two-component systems.
Figure 6 – Compartmentalized
installation of single-ply PVC
Figure 7 – Pinholing and air
bubbles in liquid-applied
Figures 8A and 8B – Hot-applied
membrane application.
J A N U A RY 2008 I N T E R FA C E • 1 1
Waterproofing membranes all require
protection during construction as well as
from ultraviolet radiation. This protection
should be applied as soon as possible after
the membrane is installed and flood testing
is concluded.
The industry’s most common material is
an asphalt-core, laminated panel with polyethylene
film on one side that prevents
sticking. The panel or board is produced in
1.5-mm (1/16-in), 3.1-mm (1/8-in), and 6-
mm (1/4-in) thicknesses. One manufacturer
produces a 2-mm (.085-in) synthetic,
fiber-reinforced, rubberized, asphalt protection
sheet in roll form for use with its waterproofing
Protection of the horizontal waterproofing
membrane is mandatory after the membrane
is installed and water testing is completed.
The sequencing of these steps –
membrane application, flood testing, and
protection board installation – must continue
without interruption. If the protection
board installation is delayed, damage to the
waterproofing membrane can occur from
some of the following construction activities
(Figure 10):
• Pipe scaffolding without proper protection,
• Stockpiled masonry,
• Reinforcing bars,
• Welding rods,
• Fasteners, or
• Loose aggregate.
All of the above items are hazards to the
membrane’s service life. A membrane is
worthless after it is damaged or destroyed
by careless construction operations. That is
why it is important to have a qualified person
inspect the membrane to ensure that
the protection board is installed after the
flood testing is completed. If the membrane
fails the flood test, the protection application
must be held until the membrane is
repaired and retested.
When a membrane waterproofing system
is applied directly to the structural
deck and then covered with a wearing surface
or overburden, it is assumed that water
will reach the membrane. If this were not
true, in this case, there would be no need
for the membrane.
According to ASTM C-981, drainage of
the waterproofed deck system should
include all components, from the wearing
surface down to the membrane. The structural
deck and the supporting columns and
walls should be properly designed to provide
positive slope. Inadequate slope to
Figure 9 – Squeegee application of cold-applied liquid membrane.
Figure 10 – Construction activities over protection board.
Figure 11 – Plastic drainage panel.
12 • I N T E R FA C E J A N U A RY 2008
drain is a common
deficiency in plaza
Drainage at the
membrane level is
required for the following
• To avoid
building up
pressure due
to collected
water against
the membrane,
• To avoid
freeze-thaw cycling of trapped water
that could heave and disrupt the
wearing surface,
• To minimize the harmful effect that
standing water may have on the
wearing surface material and membrane,
• To minimize thermal inefficiency of
wet insulation or water below the
A 2 percent (6-mm or 1/4-in-per-ft)
slope is recommended for positive drainage.
The substrate should slope away from
expansion joints and walls.
Gravel or plastic drainage panels
(Figure 11) or grooved or
ribbed insulation boards can
provide the necessary medium
to facilitate water flow to
Waterproofed decks should
incorporate multilevel drains
capable of draining all layers (Figure 12).
These drains must permit differential movement
between the strainer located at the
wearing level and the drain body that is cast
into the structural concrete slab to prevent
The drainage of a waterproofing system
at the wearing surface level can be accom-
J A N U A RY 2008 I N T E R FA C E • 1 3
Figure 12 – Two-stage plaza drain.
(Courtesy of ASTM International.)
plished through an open-joint or closedjoint
system. The open-joint system allows
rainwater to quickly filter down to the membrane
level and subsurface drainage system.
A closed-joint system is designed to
remove most of the rainwater rapidly by
sloping to surface drains and allowing a
minor portion to gradually infiltrate down to
the membrane level.
Open-joint systems include pavers on
pedestals or pavers placed directly on
ribbed polystyrene insulation boards (Figure
13). Joints should be less than 6 mm (1/4
in) wide to minimize catching high-heeled
shoes and cigarettes. Advantages are:
• Elimination of the cost and maintenance
of sealant joints,
• Easier adaptability to a dead-level
wearing surface,
• Faster and more efficient drainage,
• Easier access for cleaning and
repairs to subsurface components.
The disadvantages are:
• Rocking of improperly set pavers
due to pedestrian
• Unpleasant reverberations from heel
impact, and
• Possible hazards for pedestrians
wearing high-heeled shoes.
Closed-joint systems consist of either a
mortar-setting bed or caulked joints. This
type of construction changes the waterproofing
membrane to a secondary line of
waterproofing defense, since the majority of
rainwater is drained from the wearing surface
level (Figure 14). The closed-joint system
should slope away from adjoining walls
and expansion joints to direct water away,
both above and below the
wearing surface level. The
advantages of a closed-joint
system include:
• Protection of the
membrane from deicing
dirt, and debris,
• Its flexibility to
accommodate a
greater variety of paver types,
designs, and sizes, and
• The feeling of solidity under pedestrian
The main disadvantages are:
• It drains extremely slowly,
• It imposes a hydrostatic head of
pressure on the membrane, and
• It is difficult to access for membrane
A third system that is better than a
closed-joint system, but not as good as an
open-joint system, is one that provides for
Figures 13A and 13B – Open joint pavers on pedestals.
Figures 14A and 14B – Closed joint pavers over mortar-setting bed.
14 • I N T E R FA C E J A N U A RY 2008
brick or stone pavers in a sand-setting bed.
The selection of insulation and location
in the system are influenced by:
• Deck design,
• Environment under which it may be
• Its physical and chemical properties,
• Characteristics of the wearing surface,
• Loads to be supported.
Insulation placed over the waterproofing
membrane, protection, and drainage layer
results in maximum system benefit. When
insulation is placed in this location, the
deck and membrane are insulated against
extreme temperature cycles, and the membrane
can then function as a vapor retarder.
The location of the insulation above the
membrane also provides additional protection
to the membrane.
The choice of insulation type is limited
to extruded polystyrene (XPS) [ASTM
International C-578 Standard Specification
for Rigid, Cellular Polystyrene Thermal
Insulation]. It must be able to accommodate
the plaza dead
and live loads and
be dimensionally
stable and compatible
with the
w a t e r p r o o f i n g
membrane. It
must also be as
non-absorbent as
possible and resistant
to freeze/
thaw deterioration.
deck systems, like
roof systems, require
flashings where the membrane terminates
at walls, penetrations, and expansion
joints. However, unlike roof systems, where
the flashing installation follows the membrane
installation, flashing of waterproofed
deck terminations or penetrations is generally
installed prior to the membrane application.
Flashing Installation
Reinforce all intersections that occur at
walls, corners, or any other location that
may be subjected to unusual stress with
one additional ply of membrane.
Extend flashing membranes above the
wearing surface a minimum of 100 mm (8
in). This height is critical if the plaza design
incorporates a wearing surface with closed
joints. When the flashing extends above the
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J A N U A RY 2008 I N T E R FA C E • 1 5
Figure 15 – Gutter drain at access door with ADA grating.
wearing surface, it must be covered or protected
against exposure to ultraviolet sunlight
with sheet metal or vertical wall finishes
such as stone, stucco, etc. Some liquidapplied
membranes (LAM) are self flashing.
When 200-mm (8-in) flashing heights
are impractical, and particularly at access
doors that open onto the plaza at the same
elevation for ADA accessibility, a gutter with
grating is recommended (Figure 15).
Expansion Joints
Flashing at expansion joints located in
the field of the plaza or at rising walls
should be installed on a curb that is raised
at least 38 mm (1-1/2 in) above the structural
deck (Figure 16). This allows water to
be directed away from the joint. This
method is far superior in safeguarding
against leakage.
A less costly method is to flash the joint
at the membrane level. This method entails
greater risk than the water shed concept
since it relies on positive sealing of materials
at the membrane level, where the membrane
is most vulnerable to water penetration.
The materials used and their joining
must be carefully considered and designed.
The installation requires the highest degree
of workmanship for success without any
margin for error and is not advisable.
For moisture-sensitive occupancies,
consider using a drainage gutter under the
A reinforced concrete protection slab
that is at least 76 mm (3 in) thick is an
optional component in waterproofing systems
for both plazas and earth-covered
slabs. When a paved area is used for vehicular
traffic, a concrete protection slab is
mandatory to prevent damage and failure of
the waterproofing membrane from braking
loads, turning stresses, etc. Moreover, in a
plaza system, a concrete protection slab will
protect the membrane during subsequent
construction activities. In earth-covered
systems, it serves to protect the membrane
from root damage that may penetrate the
drainage course and protection board.
The inclusion or exclusion of a concrete
protection slab is a major design decision in
plaza waterproofing systems and balances
accessibility against reliability. Gaining
accessibility to the membrane by specifying
removable components above the membrane
is an enormous advantage. It can
facilitate repairs and membrane replacement.
Accessibility to the membrane can sacrifice
reliability. Protection boards and
drainage composite boards can provide
resistance to root intrusion for earth-covered
slabs. However, they cannot provide
the level of resistance to root intrusion that
a concrete protection slab can, or the protection
from landscaping equipment. The
decision to incorporate a concrete protection
slab must be based on cost, which
includes the initial cost of the slab and the
potential cost associated with its removal to
access the waterproofing membrane.
As stated previously, wearing surfaces
are generally divided into open-joint systems
that are drained at the membrane
level and closed-joint systems that are
drained at the surface.
Waterproofing membranes in an openjoint
system are infrequently subjected to
hydrostatic pressure exceeding 5 psf (25
mm [1 in] depth of water). Closed-joint systems
shed water at the surface and similarly
protect the membrane from hydrostatic
Any waterproofed plaza wearing surface
must satisfy the following criteria:
• Structurally sound to bear the
intended traffic,
• Durable under heavy wear and
• Resistant to abrasion,
• Aesthetically pleasing, and
• Heat reflecting.
The first two items are mandatory, and
the last two are optional.
Although beyond the scope of this
paper, earth-covered slabs can be planted
with ground cover, shrubs, and trees.
Typically referred to as green roof systems,
they are an extension of the existing roof
that involves a high-quality waterproofing
and root barrier system, a drainage system,
filter cloth, a growing medium, and plants.
Green roof systems may be modular,
with drainage layers, filter cloth, growing
media and plants already prepared in movable,
interlocking grids; or each component
of the system may be installed separately. A
green roof involves the creation of “contained”
green space on top of a man-made
In today’s environment, building owners
and architects are embracing green roof
technology. The two distinct types of green
roofs are intensive and extensive.
Extensive green roofs are much lighter
in weight with engineered soil depths ranging
from 75 mm (3 in) to 175 mm (7 in). Due
to the shallow soils and the extreme environments
on many roofs, plants are typically
low-growing ground cover that are ex-
Figure 16 – Schematic section through
expansion joints. (Courtesy of ASTM
16 • I N T E R FA C E J A N U A RY 2008
tremely sun and drought tolerant.
Extensive green roofs can be installed
over existing roof decks, provided a structural
engineer first inspects the structure to
ascertain its load capacity. Although the
focus of most extensive green roofs is their
environmental benefit, extensive green roofs
still require periodic maintenance and must
be designed to resist wind uplift.
Intensive green roofs are characterized
by thick soil depths (200 mm – 1.2 m [8 in –
4 ft]), heavy weights, and elaborate plantings
that include shrubs and trees.
Intensive green roofs are installed primarily
over concrete roof decks to withstand the
weight requirements. These park-like green
roofs can be at or above grade and require
considerable maintenance to sustain their
aesthetic appearance.
If a plaza design includes planters, reflecting
pools, foundations, benches, and
other plaza “furniture,” they should be installed
over the waterproofing membrane.
These items should be waterproofed individually
and not integrated as part of the
primary waterproofing membrane. Trees
should be planted in concrete containers
(Figure 17) to avoid damage from root penetration
or landscape shovels.
A failed waterproofing system is more
destructive and expensive to correct than a
failed roof. The replacement cost of a failed
roof can be anywhere from $15 to $22 psf;
a failed waterproofed plaza, between $75
and $125 psf, at a minimum.
It is therefore advisable to flood-test a
waterproofed deck after the flashing and
membrane have
been installed.
ASTM D-5957,
Horizontal Waterproofing
published in
1996, provides
the necessary
method for testing
the watertightness
of a
deck (Figure
18). Some limitations
of this
standard are:
• S l o p e
of deck or membrane to be tested
must not exceed 2 percent (6.25 mm
[1/4 in]) per foot).
• Membranes should be LAMs,
adhered or loose-laid sheets, builtup,
and modified membranes.
• Testing should not take place until
24 hours after the membrane has
been installed. (This requirement
increases to 48 hours if the membrane
was installed at ambient temperatures
below 50˚F.)
• Flashing and membrane must be
inspected and repaired prior to testing.
If a leak occurs during the test process,
the following provisions are to be followed:
• Drain water.
• Locate and repair leak.
• Retest area under the same initial
Electric field vector mapping (EFVM™)
is a tool for improving quality control of waterproofing
systems. Although relatively
new to the United States, it has achieved a
long record of success in Europe. The system
was pioneered in Germany. EFVM, unlike
other leak-detection methods, can
quickly and accurately locate the point of
water entry.
EFVM uses water as an electrically conductive
medium. A wire loop is installed
around the perimeter of the area to be tested
and introduces an electrical potential.
The area within the loop is dampened and
J A N U A RY 2008 I N T E R FA C E • 1 7
Figure 17 – Planter containers.
forms the upper electrical plate. The structural
deck then becomes the lower plate. The
membrane acts as separator and insulator
between the two plates. If moisture enters a
defect in the membrane, an electrical contact
is established. The survey technician
can then follow the direction of the electric
field to the membrane defect. Advocates of
EFVM state that the test method:
• Locates defects precisely, enabling
efficient repairs.
• Enables immediate retest of repairs.
• Can be used after cover systems are
installed, especially with green roof
• Is less expensive than conventional
flood testing.
• Eliminates the hazard of overloading
structural decks during testing.
• Can be used on steeply sloped roof
surfaces where flood testing is
The suitability of EFVM depends on the
electrical resistance of the waterproofing
materials, so all membranes may not be
compatible with this test method. Systems
that employ a root barrier require special
procedures, since the root barrier will act as
an insulating layer. When a root barrier is
used, it is necessary to make small slits in
the barrier to permit the establishment of
electrical contact with the underlying waterproofing
membrane. These cuts can be resealed
after the leak is located.
A plaza design over occupied spaces
must create a system that waterproofs and
insulates the structural building deck while
supporting pedestrian and/or vehicular
traffic, as well as landscaping elements.
The building deck must be reasonably
smooth, sound, and provide adequate slope
to promote drainage. The waterproofing
membrane selected and
installed must be capable of withstanding
long-term exposure to ponding water. Flashings
at drains, penetrations, expansion
joints, and other similar membrane terminations
should be carefully detailed, since
most leakage problems occur at these locations.
Insulation should be placed above the
membrane to minimize temperature cycles
of the membrane and deck and provide additional
protection for the membrane. The
insulation must have high compressive
strength, low water absorption, and be
resistant to freeze/thaw.
Drainage at the membrane level is an
essential component of the system. Drainage
at both the membrane level and below
the wearing surface is particularly important
to ensure water flow to drains and minimize
freeze/thaw heaving or deterioration
of the wearing surface.
The wearing surface should be aesthetically
pleasing, durable, and able to accommodate
loads associated with the plaza
function. The wearing surface should consist
of discrete components to facilitate
removal and reinstallation and to allow for
EDITOR’S NOTE: This paper is reprinted
from the Proceedings of the 2007 RCI Symposium
on Building Envelope Technology,
Nov. 8-9, 2007, in Boston, MA.
Buccellato, Paul, “Below-Grade Waterproofing
Selection Process,” Proceedings of
the 2006 RCI Building Envelope Technology
Symposium, Washington, DC, RCI, Inc.
Buccellato, Paul, “Principles for Better
Waterproofing,” Proceedings of the 2002 RCI
Building Envelope Technology Symposium,
Coral Springs, FL, RCI, Inc.
Henshell, Justin, The Manual of Below-
Grade Waterproofing Systems, 2000, John
Wiley & Sons, Inc., New York, NY.
Kubal, Michael K., Waterproofing the
Building Envelope, McGraw-Hill, Inc., New
York, NY.
Parise, Charles, Waterproofing Structural
Concrete Decks over Occupied Space, 1981
American Concrete Institute’s SP-70.
Simpson, Gumpertz & Heger, The
Building Envelope: Solutions to Problems.
Paul Buccellato is a registered architect in four states and
holds a certificate from the National Council of Architectural
Registration Boards. He is also a Registered Waterproofing
Consultant with RCI. Buccellato is a member of the American
Institute of Architects, the New Jersey Society of Architects,
the Construction Specifications Institute, RCI, and ASTM,
Committees D-08 Roofing and Waterproofing (chairman
Subcommittee D08.20 Roofing Membrane Systems), C-15
Masonry Units, and C-24. Mr. Buccellato has authored several
technical papers on waterproofing and roofing, four ASTM standards on roofing and
waterproofing, and has lectured at Brookdale College, NJ. He wrote a column on roof
design for The Roofing Specifier and is coauthor of an NCARB monograph on built-up
roofing. He has presented papers relating to waterproofing and roofing for RCI and
ASTM. Paul is a member of RCI’s Education and Waterproofing Examination
Committees and of NRCA’s Educational Resource Committee.
Paul Buccellato, RWC,AIA, FASM
18 • I N T E R FA C E J A N U A RY 2008
Figures 18A and 18B – Flood-testing. (Sketch courtesy of ASTM