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CONSTRUCTION CHEMICALS
FOR WATERPROOFING IN
CONCRETE STRUCTURES
GUIDED BY
PRESENTED BY
DEEPTHY DAS
INTRODUCTION
Permeability is one of the main factors that can affect
the durability of the structure.
 Permeable structures can result for various reasons
such as low cement content, poor compaction too
much water during concrete mixing etc.
 The passage of water through cracks ,joints, voids,
and inter connected capillaries in the mass concrete
makes the concrete pervious, ultimately leads to poor
protection of structures, increases the rate of alkali
aggregate reaction and also accelerates the rate of
CONTIN…………………

The impervious property of concrete can be
improved by addition of admixture in the green
concrete or by surface treatments and the
phenomenon is generally known as waterproofing.
The products used in both the stages of concrete
are known as construction chemicals or
admixtures and waterproofing is one of the aspects
in construction aid.
 These products are required for modifying the
CONSTRUCTION
CHEMICAL FOR WATER
Integral water proofing
compounds
PROOFING
 Acrylic based polymer coatings
Mineral based polymer modified coating
Chemical DPC for rising dampness
Water proofing adhesive for tiles, marble and granite
Silicon based water repellent material
Injection grouted for cracks
Protective and decorative coatings
New Innovative Products
 Mainly Thermo set Polymer
 Chemical cross linkage
 Main characteristics of thermo set polymer are once they
are fully cured they can be bonded to like material with an
adhesive.
 The four common sub categories of thermo set roof
membranes are
 Neoprene(CR)
 Chlorosulfonated Polyethylene (CPSE)
 Epychlorohydrine (ECH)
Thermo Plastic Membranes
There is no chemical cross linking
 mainly seven type
 Poly vinyl Chloride (PVC)
 Copolymer alloy (CPA)
 Ethylene Inter polymer (EIP)
 Tripolymer Alloy (TPA)
 Nitrile Alloy (TPA)
 Chlorinated Polyethylene (CPE)
Types of Integral Water
Proofers
 Water proofing admixtures can be broadly grouped as
(a) permeability reducers
(b) Water repellents or hydrophobic (water hating)
agents.
Permeability reducers are pore filling and porosive
reducing materials which can be further classified into:
(a)very fine particulate matters
(b)workability and air entering admixtures
PERMEABILITY REDUCERS
 Ground Sand, lime stone (powdered),slag, colloidal silica,
flouro silicates main product
Powdered form.
Plasticizers and workability agents obviously avoid the
presence of large voids and higher water requirements as
per their advocated use.
 The plasticizers generally work by giving better
disperation of cement and simultaneously reducing the
surface tension of the water/aqueous phase.
 This results into better wetting and proper hydration
water proofers
 Water repellent coatings, which can be applied on the concrete
surface to impart water proofing to the concrete structure.
 Thermoplastic PU has been used in the water proofing of below
grade structures building foundation, basements, reservoirs, ponds,
walkways, tunnels, earthen shelters, bridge, abutments, retaining
walls, landfills and water canals.
 Acrylic co polymer emulsion based additive for cement based
coatings when mixed with cement gives excellent water proofing,
excellent adhesion to concrete substrate, steel, asbestos, excellent
resistance to ultra violet rays, excellent breathing properties and
helps in reducing corrosion of reinforcement.
 Styrene butadiene co polymer emulsion have also been used as
water proofing coating for concrete, which also increase adhesion
APPLICATION
PROCEDURES
METHOD OF THE APPLICATION
Cementitious
Substrate
Application of 1st coat of Dr.
Fixit New coat
Application of 2nd coat of Dr.
Fixit New coat
Application of Dr. Fixit Prime seal
Roller Application of Dr. Fixit New
coat
Application of 3rd of Dr. Fixit New
coat
Preventive measures
New Structures (During Construction)
 Calculated quantity of BBR Microdite is mixed with the
concreting mixture and the percentage is to be decided on
the basis of the quality of sand;
1. New roof-Bad quality of sand: Upton 0.6% (300 gms. per
bag of cement).Good quality of sand: It can go down up to
0.2%
2. New bathroom-2%
3. New toilet-First coat with 2% & second coat with 20%
Continue………….
4.New water tanks-Either uses the product during construction as
a pre-mix or after construction as a coating.
5. Crack filling- In new structures if care is taken to mix BBR
Microdite in plastering mixtures, concrete mixtures etc. during
construction no problem of crack formation would arise in the
future.
6.POP - Suggested dose of Microdite: 2% w.r.t. white cement
(100 gms. of Microdite + 5 kgs. of white cement + 5- 6 liters. of
water).
Restoration (Cure) of Old Structures
1.Old roof
•
two coat of microditemixture.
•
2% of microdite.
•
Coverage area 400-500sq.ft
2. Old flooring-Concentration of Microdite mixture for soaking:
(1:5:7; i.e.1 kg. of Microdite+5 kg. of cement+7 liters. of
water) Percentage of Microdite in cement paste:2% (20 gms.
for 1 kg. of cement)
4. Crack – filling
 Hairline Cracks
•
Hairline cracks get filled automatically when the coating is
given in the usual way using Microdite-Cement-Water
mixture.
•
Cement can be substituted by synthetic primers to avoid
curing.
•
Suggested percentage of Microdite: 2-5 %

Bigger Cracks:
•
For filling of smaller cracks, cement paste mixed with BBR
Microdite can be conveniently.
THE LATEST TRENDS IN
WATERPROOFING
The following methods can be
used to achieve this:
1.Use of Water tight concrete
For any kind of structure and
especially for structural elements
like foundations, slabs and shear
walls, the main aim of
Using PCE polymers
Figure 1: Mechanism of action for PCE
Polymers
Use of Condensed Silica Fume or
Aluminosilicates in concrete
 Again it is well-known that Condensed Silica Fume or
Aluminosilicates are extremely fine materials that function
both as micro fillers as well as pozzolanic materials that
hydrate in the presence of the Calcium Hydroxide in
Concrete.
 The combined effect of these materials as micro fillers
and hydrating materials help close capillaries in concrete,
thereby rendering it waterproof
Using Integral Waterproofing
Compounds working by Dynamic

Figure shows the progressive refinement of pore volume in concrete by
syncrystallization
DySCTechnology. This shows that progressive crystallization reduces overall pore
volume of the concrete thereby rendering concrete waterproof.
Shows pore volume of a
product using DySC
Technology
Shows progressive pore
volume reduction using
DySCTechnology
2. Liquid Applied Membranes
BASEMENT
WATERPROOFING
 Shovel a trench below the level of your basement all the
way down to the concrete footings. Do this around the
entire perimeter of your foundation.
Apply a Portland cement-based waterproofing seal with a
trowel and fill in small cracks or holes in your foundation.
Reseal any mortar joints between cinder-block walls. Let
the cement dry before proceeding
Fill the pump sprayer with the urethane sealant. Saturate the
foundation walls with the sealant by spraying it thoroughly
with the pump sprayer. This will prevent additional cracking
in the foundation.
5. Pour a few inches of washed gravel into the trench. Lay out a line
of the plastic piping with holes, placing it on top of the gravel.
Extend the piping around the perimeter of the foundation.
6. Fill the trench with the washed gravel up to a few inches from the
top. This should equal at least 3 feet.
7. Cover the gravel with another layer of the tar paper. Wrap it
around the gravel
8.Shovel topsoil over the top of the sheeting. Slope the soil using the
shovel and a rake to angle it away from your house.
MARKET SIZE
 The market size for waterproofing material and compounds is
estimated to be around Rs.600-800 cores per annum.
 Out of this chemical waterproofing will be around Rs.100
cores and the rest comprises of large group of products.
 With the introduction of newer products like APP modified
SBS, EPDM, TPO and PVC membrane the market is ready to
grow at a rate of 35-50% in the near future
 APP/SBS modified membrane has already been accepted as a
durable waterproofing system and this enjoys a market share of
Rs.250 cores.
CASESTUDY
Waterproofing and Restoration Of
8000m2Hyperbolic Parabola Shell Roofs In
Nepal
 Type of the Structure: Framed
 Type of roofing: Shell (Hyperbolic Parabola)
Structure
 Year of Construction: 1950
 Year of Completion: 1956
 Phosphate based rust remover cum passivator
RUSTICIDE was used to clean the corroded
reinforcement.
 Alkaline pure acrylic based Corrosion Inhibitor
POLYALK FP was used for passivating the
reinforcement from further corrosion and to maintain
passive layer around the reinforcement.
 Spalled concrete cover was replaced with Polymer
Modified Mortars with a polymer content of 20% in
the mix.
 POLYALK EP which is an acrylic polymer admixture
used for bonding and for modifying the properties of
The expansion joint was filled with wooden planks
covered by a metal plate over which a layer of tar felt with
5mm down aggregates was laid.
 A high performance two polysulphide sealant
SUNJOINTSEAL was used in all the expansion joints of
the school building.
The works were completed in June 2001 and since then,
till date there is no major leakage in the structure unlike
the earlier scenario and will never be for many years to
come either.
 Waterproofing and structural repair & rehabilitation job
undertaken of the Laboratory Higher Secondary School
was the first of its kind in Nepal.
 The rehabilitation techniques using equipment like
CONCLUSION
 At present there are about 100 types of construction
chemicals available in the market and the range continues
to expand as there is constant spree for quality
enhancement.
 In order to enhance the life of concrete structure the use
of construction is of great importance.
 The construction chemicals are basically inorganic or
organic materials or minerals, which when added to the
concrete admixture enhance the life of concrete imparting
them special properties as well result in the delay in the
initiation of corrosion of steel rebar.
REFERENCES
I.Supradip Das“Emerging trends in construction chemicals
and waterproofing” civil engineering &construction review
vol: 25 no: 02 feb2012
II.Col Harry Sidhu“The Essentials Of Waterproofing”
Civil Engineering
&Constructionreview vol :25 no:02
feb2012
III.M.S Shetty Concrete Technology
IV.Sunny Surlaker“Waterproofing Best Practices” New
Building Material