water proofing-residential buildings

8/11/2019 Water Proofing-Residential Buildings

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WATERPROOFING OF BUILDINGSWaterproof or water-resistant describes objects unaffected by water or resisting water passage, or

which are covered with a material that resists or does not allow water passage. Such items may

be used in wet environments or under water. Waterproofing describes making an object

waterproof or water-resistant.

Waterproofing is a method by which an item is made resistant to damage by water.

Waterproofing is the formation of an impervious barrier which is designed to prevent water

entering or escaping from various sections of building structures. Internal areasthat are

waterproofed include bathrooms , shower recesses , laundries and toilets . Whilst an External

area waterproofed extends to roofs , planter boxes , podiums , balconies ,retaining

walls and swimming pools .

Waterproofing is the combination of materials or systems that prevent water intrusion into

structural elements of the buildings or its finished spaces. Basic waterproofing and envelope

design incorporates 3 steps to ensure a watertight and environmentally soundinterior :

1. Understanding water sources likely to be encountered

2. Designing systems to prevent leakage from these sources. 3. Finalizing the design by properly detailing each individual envelope component into adjacent

components.

CAUSES OF LEAKAGE

For leakage to occur, 3 conditions must be present

Water in any of its forms must be present.

Water must be moved along by some type of force, including wind, gravity for above-grade

envelope components and hydrostatic pressure or capillary action for below-grade components.

Finally and the most important, there must be a breach (hole, brak, or some type of opening) in

the envelope to facilitate the entry of water into the protected spaces

Available water is moved into the interior of a structure by numerous forces that include:

Natural gravity

Surface tension

Wind/Air currents

Capillary action

Hydrostatic pressure

The first 3 typically are encountered on above-grade portions of the envelope, whereas the last 2

are recognized at grade or below-grade areas of buildings or structures



WATERPROOFING IN CONSTRUCTION

In construction, a building or structure is waterproofed with the use of membranes to protect

contents underneath or within as well as protecting structural integrity. The waterproofing of the

building envelope in construction specifications is under '07 - Thermal and Moisture' protectionand includes roofing material as well aswaterproofing materials.

A building or structure needs waterproofing as concrete itself will not be watertight on its own. The

conventional system of waterproofing involves 'membranes'. This relies on the application of one

or more layers of membrane (available in various materials: e.g., bitumen, silicate, PVC, HDPE, etc.) that

act as a barrier between the water and the building structure, preventing the passage of water. However,

the membrane system relies on exacting application, presenting difficulties. Problems with application or

adherence to the substrate can lead to leakage.

Over the past two decades, the construction industry has had technological advances in waterproofing

materials, including integral waterproofing systems as well as more advanced membrane materials.

Integral systems work within the matrix of a concrete structure, giving the concrete itself a waterproof

quality. There are two main types of integral waterproofing systems: the hydrophilic and the hydrophobic

systems. A hydrophilic system typically uses a crystallization technology that replaces the water in the

concrete with insoluble crystals. Various brands available in the MARKET claim similar properties, but

not all can react with a wide range of cement hydration by-products, and thus require caution.

Hydrophobic systems use fatty acids to block pores within the concrete, preventing water passage.

New membrane materials include

Hydrotech’s Monolithic Membrane 6125 (MM6125) and

Re-New’s Turbo Seal.

These new materials seek to overcome shortcomings in older methods like PVC and HDPE. Generally,

new technology in waterproof membranes relies on polymer based materials that are extremely adhesive

to create a seamless barrier around the outside of a structure.

If we bifurcate a structure in to different categories with respect to waterproofing perhaps we can

classify the structure in to following: -

1. Waterproofing of foundations

2. Waterproofing of basements

3. Waterproofing of bathrooms and toilets,

4. Waterproofing of terraces

Waterproofing of the above mentioned areas needs a detailed site investigation in case of

old construction but in new construction if the proper methodology and proper materials are used

the structure can be made waterproof for period of five years extended to twenty years depending

on the materials used for waterproofing. In this project, we will try to understand different

techniques used to waterproof foundations and basements only but before that we will try to

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understand what are the methods used in waterproofing any part of structure with the help of an

flowchart.

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DAMPNESS AND ITS EFFECTS

A wet cellar can dramatically reduce the value of your home. Studies show that most people won't even

consider buying a home with water leakage. Selling a home with water leaks can easily result in as much

as a 25% reduction in the sale price.Even if you rarely have problems with dampness or flooding, it's best to solve the problem completely

before doing any remodeling work. Permanent solutions can take time to implement. A good place to start

is to talk to an independent home inspector who specializes in waterproofing problems.

Proper insulation is critical to creating a comfortable, dry basement. Besides keeping out the cold,

basement insulation prevents condensation. The ground stays cool year round. It in turn keeps basement

walls cool. When the warmer air in the room comes in contact with all those cool walls, it has to give up

some of its moisture in the form of condensation. In fact, condensation is the primary source of the

moisture that causes mold and mildew problems in basements. Effective insulation separates the warm

air of the room from the cool walls, thereby preventing the moisture problems that stem from

condensation. (see below the top-10 most common insulation mistakes in basements)

1. DEFECTS CAUSED BY DAMPNESS:-

The various defects caused by dampness in buildings may be summarized as under:

1. It causes efflorescence which may ultimately result in disintegration of bricks, stone,

tiles, etc.

2. It may result in softening and crumbling of plaster.

3. It may cause bleaching and flaking of paint with the information of colored patches.

4. It may result in warping, buckling and rotting of timber.

5. It may lead to corrosion of metal

6. It may deteriorate electrical fittings. 7. It promotes growth of termites.

8. It breeds mosquitoes and creates unhealthy living conditions for the occupants.

2. CAUSES OF DAMPNESS

Absorption of moisture by the building materials is one of the chief cause of dampness. On

account of granular nature of materials, moisture finds an easy access through the voids and this

aided by capillary action assists the moisture to travel in different directions. Thus, either on

account of faulty design of structure or bad workmanship or by use of defective materials,

moisture may find its way to interior of the building either through the foundation and plinth,

walls, chhajjas, floors or the roof.

3. SOURCES OF DAMPNESS

The important sources of dampness may be summarized as below:-



1. Dampness rising through the foundation walling. Moisture from wet ground may rise

well above ground level on account of capillary action.

2. Splashing rain water which rebounds after hitting the wall surface may also cause

dampness.

3. Penetration of rain-water through unprotected tops of walls, parapets, compound walls

etc. may cause dampness. 4. In case of slope roofs rain-water may percolates through defective roof covering. In

addition, faulty eaves course and eaves or valley gutter may allow the rain-water to descend

through the top of supporting wall and cause dampness.

5. On condensation, the moisture present in the atmosphere gets deposited on the

components of the building which may cause dampness.

6. In case of flats roofs, inadequate roof slopes, improper rain-water pipe connections and

defective junction between roof slab and parapet wall may prove to be the sources of dampness.

Dampness caused due to leakages in wet areas of a building which include kitchen, bathroom,

water closet etc. The leakages could be on account of use of sub-standard plumbing fittings andfixtures as well as faulty execution of work and bad work-man ship.

4. SURFACE TREATMENT

The moisture finds its way through the pores of materials used in finishing. In order to check the

entry of the moisture into the pores, they must be filled up. Surface treatment consists in filling

up the pores of the surface subjected to dampness. The use of water repellent metallic soaps such

as calcium and aluminum oleates and stearates is much effective in protecting the building

against the ravages of heavy rain. Bituminous solution, cement coating, transparent coating, paints and varnishes fall under this category. In addition to other surface treatments given to

walls, the commonly used is lime cement plaster. The wall plaster with cement, lime and sand

mixed in proportion of 1:1:6 are found to serve the purpose of preventing dampness in wall due

to rain effectively.

5. MATERIAL USED FOR WATER PROOFING

An effective damp proofing material should have the following properties:

1. It should be impervious. 2. It should be strong and durable be capable of withstanding both dead as well as live

loads without damage.

3. It should be dimensionally stable.

4. It should be free from deliquescent salts like sulphates, chlorides and nitrates.

The material commonly used to check dampness can be divided into the following four

categories:



1. Flexible material:- material like bitumen felts ( which may be Hessian – base or

fibre/glass fibre-based) , plastic sheeting ( polythene sheet) etc.

2. Semi-rigid material: - Material like mastic asphalt or combination of material or layers.

3. Rigid material:- Material like first class bricks, stones, slates, cement concrete etc.

4. Grout consisting of cement slurry and acrylic based chemicals/polymers.

6. SIGNS THAT YOU HAVE WATERPROOFING PROBLEMS IN YOUR BASEMENT

Mold and Mildew

Fungus that grows in damp and dark areas, and cause discoloration, or musty odors.

Moldy Odors

This is the result of the decay process from mold, and dry rot.

Peeling Paint

Peeling paint is a sign that you have moisture problems and waterproofing issues.

Damp Spots on Walls

Water has absorbed through your walls.White Substance on Basement Walls

This is a chemical breakdown of the bonding agent that holds your walls together. This white substance is

a sign of possible structural deterioration.

Cracked Walls

Should be inspected to determine the exact cause.

Rust on Appliances or Furniture

Like furnaces. Rust is caused by a wet environment and is the sign of waterproofing issues.

Dry Rot

Black fungus grows mostly on walls or wooden surfaces, causing wood to decay.

Basement Waterproofing

Water may enter a basement through various means including through joints, walls, or floors.

Various basement waterproofing systems address these problems. There are many systems

available of varying cost, effectiveness, and installation invasiveness.

We shall now discuss few methods of waterproofing basements.

7. WATER PROOFING TREATMENT BY USING GROUT CONSISTING OF CEMENT

MORTAR ADMIXED WITH ACRYLIC BASED CHEMICALS ALONG WITH ROUGH

STONE SLABS:-

This treatment is presently being commonly adopted for ensuring water tightness of basement in

damp soil or at site where sub soil water table is high. The treatment consists in enclosing the

entire basement with in a water proof box constructed by use of rough stone slabs and cement

mortar admixed with acrylic based chemical.



The steps are as followed:-

Step 1:- The excavation of the ground for the basement is carried out in such a way that a

working space of at least 750 mm is available around the periphery of the external walls of the

proposed basement. The excavated area is kept dry by continuous pumping using well-point

equipment or by adopting any other suitable method. Over the dry leveled ground a 75 to 100

mm thick layer of lean concrete 1:3:6 is laid to serve as mud mat or leveling course for the raft

slab. This layer of lean concrete should project by 150 mm beyond the external wall. Over the

layer of lean concrete a layer of 15 to 20 mm thick rough quarry-finished stone slabs is laid over

20 mm thick cement mortar (1:4) admixed with acrylic based chemical. The stone slabs are laid

side by side leaving a gap of about 15 to 20 mm between them. The joints thus left are raked

open and ground with cement slurry admixed with acrylic based chemical. A 20 mm thick layer

of cement mortar (1:4) admixed with acrylic based compound is laid over the stone slabs stone

chips 12 mm & down are embedded at random in this layer of mortar.

The total maximum thickness of the above water proofing layer should be around 6 60

mm. This layer should cover the entire area of lean concrete i.e. it should be extended 150 mm

beyond the external face of raft slab/walls.

Step 2:- The R.C.C. raft slab suitably designed to with stand the highest applicable water

pressure during monsoon is laid over the water proofing layer in step 1. The R.C.C. walls of the

basement are constructed monolithically with the R.C.C. raft. After the curing of the R.C.C. wall

is over, the water proofing treatment is continued unbroken on the external sides of the walls, soas to form an external box of the water proofing level.

Step 3:- To continue the treatment along the vertical plane, a groove about 30 to 40 mm deep is

made in top mortar layer or bottom layer of the water proofing treatment [laid in step (1) ]at a

clear distance of about 18 mm from the external face of the wall all along the periphery of the

basement. Rough quarry-finished stone slabs 15 mm to 20 mm in thickness are fixed vertically in

the above groove.

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The stone slabs are fixed side by side without leaving any gap between the edges.

Maximum of two to three horizontal layers of stone are laid at a time one over the other

vertically up. A coat of very rough cement plaster (1:4) is applied to the external face of the

rough stones. After the layer is set, the gap between the wall and stone layer is filled with a grout

made up of cement slurry admixed with acrylic based chemical, which on gellation forms an

impermeable layer, monolithic with the external face of the wall. A final coat of 15 mm cement mortar plaster (1:4) is applied over the rough external

cement plaster and finished smoothly. This treatment to external face of walls is continued up to

300 mm above ground level. The acrylic based chemical is normally added @ 1 % i.e. 1 kg of

chemical to be mixed with 100kg of cement.



8. WATERPROOFING USING FLEXIBLE PVC WATERBARS

Description: - Waterbars are flexible PVC water stops to seal construction and expansion joints

in concrete structures.

Uses: - Waterbars are used in concrete for the sealing of construction and expansion joints. It is

installed in a specified position, allowing concrete to be poured around it. The material takes up

it’s function as a joint sealant once the concrete has hardened and a joint has been formed.

Depending on the type of Waterbar, it can be used for construction or expansion joints.

Advantages: -

Multi-rib sections provide a tortuous path and impenetrable water check.

Easy to fix using tie-clips (See below photo)

Easy on-site welding.

High strength PVC material.

Specifications: - Waterbars comply with: U.S. Corporation of Engineers Specification. CRD-

C572-74. Requirements of BS2571 and BS2782.

Application: -

SURFACE WATERBARS: Installed into the face of the concrete structure. The waterbar is

typically fixed on the water side of the concrete wall or floor, by attaching it temporarily to the

formwork using fixing wire. The protruding ribs become cast into the concrete to provide an

excellent watertight seal as well as securely anchoring the waterbar to the structure.

INTERNAL WATERBARS: The waterbar is fitted into split formwork or shuttering for

casting centrally into the concrete. Use fixing wire or tie-clips to attach waterbar to internal

reinforcement.

WELDING: Waterbars are made from thermoplastic PVC and cantherefore be welded. The

ends are heated with on-site welding equipment until the PVC becomes plastic and is then

immediately pressed together. Waterbars allow easy on-site welding, including the prefabrication

of cross, T, L and corner pieces.



Profiles: -

Centerstop: - Centrally placed Waterbars O type section is used in expansion, contraction and

construction joints. The bulb in the centre allows for movement in the structure to be

accommodated for. The waterstops are easily anchored to the steel reinforcement using special

tie-clips.

Rearguard Construction: - The externally placed rearguard Waterbars AR sections are used

in construction and contraction joints. The centrally placed fin assists with shutter locations.

Rearguard Expansion: - The externally placed rearguard Waterbars DR sections are designed

with a flat top box section, with a protruding fin, to assist with positioning and to provide a chair

to support the joint filler. The section is used in expansion joints to accommodate movement.

Intersection: - A wide range of standard intersection pieces are available. All have a minimum

200mm free leg, allowing easy butt-welding on site. For nonstandard types, drawings must be

provided, giving exact details of angles and length of legs. Standard intersection pieces include:

X, T and L pieces both flat and on edge.

Technical Data: -

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Basis : Polyvinyl Chloride

Colour : Yellow

Density : 1.3kg/litre

Service Temperature : -35°C to 55°C

Hydrostatic Head : Up to 60 metres

Joint Movement : Up to 10 mm (expansion joint profiles only)

Tensile Strength (ASTM-D412-75) : longitudinal > 13 N/mm² transverse

> 12.5² N/mm2

Elongation at Break (ASTM-D412-75) : longitudinal > 310% transverse >

260%

Alkali Resistance (CRD-C572-65) : Passed

Important: - Good placement practice must be followed to ensure that concrete is well placed

and compacted around the Waterbar during installation. In the case of factory made junctions,

where angles are not 90°C, drawing must be provided giving exact joint details. Other profiletypes and widths are available upon request (depending on volume).



9. WATERPROOFING USING LIQUID APPLIED CEMENTITIOUS MEMBRANE

Description: - Liquid Applied Cementitious Membrane is the materials which are available in two

components and sometimes three components depending on the manufacturer. The two components

consist of Liquid and Powder. The Liquid is a mixture of polymers and water, these polymers acts as

strength providing material when mixed with Powder which is generally a cement based material. Is a

high performance two component flexible acrylic polymers modified cement based waterproof coating for

concrete and masonry surfaces. The system consists of a powder and a liquid, is grey in colour and

easily applied by brush.

Features and Benefits: -

Provides excellent impermeable coating

Heavy duty waterproof coating

Good adhesion with cementitious surfaces

Applied for Positive & negative sides of waterproofing

Easily Brush applied

Flexible enough to take care of minor cracks in concrete & plaster

Durable & economical

Non-flammable

Application tools easily washed in water

Available in pre-packed, ready-to-use containers

Method of Application: -

The RCC walls and the base slab of basement must be cured for 28 days minimum before

applying liquid applied cementitious membrane. The condition of walls and base slab must be

assessed carefully for any irregularities and cavities. All the cold joints must be inspected for its

water tightness. If required, inject cement slurry admixed with expansive grouts should beinjected into the cold joints.

Prepare the surface carefully to receive the first coat of the material. All the loose particles and

debris must be removed with the help of wire brush. The grouting holes must be finished to level

and ensure that they are properly sealed with suitable material.

The entire area must be thoroughly wetted with water to a state where it is saturated. But extra

care must be taken to see that there is no stagnant or standing water. Any such water must be

mopped off. As such, the concrete substrate to receive the treatment must be in a Saturated

Surface Dry Condition.

Mix both the parts i.e. Liquid and Powder with a slow speed (100 - 150 RPM) forced action

mixer for big quantity of 15 kg, to achieve an even consistency. All the powder lumps formed during mixed must be hand crushed completely. PLEASE DO

NOT ADD WATER during mixing. For large application areas, take up a quantity that can be

mixed and applied in 20 - 30 minutes.

ALWAYS ADD the POWDER component into the LIQUID and NOT the LIQUID into the

powder.



Over the properly pre-wetted surface, apply first coat at a thickness of 500-600 microns and

allow it dry for 5-6 hours. Apply the 2 coats at the same thickness. The total applied thickness

should be of minimum 1.5 mm in three coats.

Allow each coat to dry sufficiently before applying next coat.

Allow Dr. Fixit Pidifin 2K film to air cure for atleast 72 hours.

Precautions and Limitations: -

Must be protected from foot traffic & other physical abuse

Do not pond with water immediately after the 2nd coat. Allow it air to cure for atleast 72 hours

Pre-wetting of the substrate is essential before coating

Film thickness of 1 to 1.2 mm must be achieved in 2 coats. For a critical areas 1.5 mm thick film

is recommended to be achieved in 3 coats

Must be applied on totally cured surface

Do not undertake application in hot sun (above 300C) and below 100C

Do not dilute product with water at site.



10. WATERPROOFING OF BASEMENTS USING TORCH – ON MEMBRANES

These membranes are perhaps the best for waterproofing of terraces having large spans, also

when the concept of terrace garden or roof swimming pools is used. It is entirely a bituminous

product and requires a primer and the membrane for application on to the surface. The membraneis slightly melted with the heat which is shown in the pictures and thus the best waterproofing

can be achieved for atleast 25 years. The finished membrane is over coated with a paint of

aluminum to give heat proofing.

Primer application: -

Apply solvent-based bitumen primer on cleaned & leveled surface @ 3-5 sq.mtr/ltr. The priming

will enhance the adhesion of the membrane to the substrate. Allow the primer coat to dry. The drying will

generally depend on the ambient temperature.

Membrane Application

Starting from one end, unroll the TORCHSHIELD roll once the priming coat is dried. Align

the TORCHSHIELD roll correctly & re-roll it half in alignment before torching. Avoid shifting of themembrane while torching Use gas burner to heat substrate & underside to softening points. When the

embossing disappears, roll forward & press firmly against substrate. Ensure sufficient bleed on side &

end over laps. Once the half of the roll is torched properly to the substrate, unroll the balance roll and

repeat the process. An overlap of 100-mm shall be maintained for all the continuing sides. Heating shall

be done on both the membranes to be overlapped and pressed firmly with the help of round shape trowel.

The care shall be taken to leave no gap at any point in the overlapped area. If noticed, reheating shall be

done to seal it. The Torchshield must be laid over the entire PCC area with a minimum of 150 mm over

hang from the size of raft on all sides.

Protection

The Torchshield membranes shall be protected against damage by laying sand cement mortar in

1:4 ratio at 15 to 20 mm thickness. Cure the surface for 7 days before starting the work for laying RCC

raft or column footings.

Method of Application

The entire external surface of the wall shall be prepared properly and made ready to receive the

waterproofing treatment. All the honeycomb areas, undulations, cracks shall be filled with polymer

modified mortar. For which Dr. Fixit Polymer Mortar PX shall be used as per the standard material

specification.

Primer Application

Bitumen based primer shall be applied as explained above over the entire surface and

shall be allowed to dry.

Membrane Application Torchshield shall be applied as per the standard installation practices as explained above

over the dried primer. Before the application of Torchshield begins over the wall, a corner

rounding / angle fillet shall be made at the junction of PCC and Raft to avoid the right angle

bend of membrane.

The application of membrane shall begin from the edge of PCC with a sufficient lap of 100 mm

minimum with the bottom membrane (over PCC) and to be taken over raft thickness and then

over the wall. An overlapping of 100 mm must be ensured with the subsequent membrane with

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all sides. The fixing shall be done from the PCC level moving horizontally first and then

vertically. All the lap joints and termination shall be done as per standard specifications as

explained earlier.

Clean & remove dust, dirt,

loose particles and unsound

substrate

Apply primer coat with

solvent based bitumen primer

Unroll the TORCHSHIELD

roll

Align the Torchshield Roll

Use gas burner to heat

substrate & underside to

softening points

Keep overlap margin for

minimum 100 mm

Heat both the overlaps & use

round tipped trowel to seal

overlap

Seal the edges well

and protect with a

Polysulphide sealant

Torchshield applied all over

the terrace

Protection

The back filling can start simultaneously as one move upward. Before back filling begins,

the membrane shall be protected either with plaster or with a protection board.

For plaster, sand shall be sprinkled over the membranes as soon as it is fixed after torching. The

plastering shall be done in 1:3 sand cement mortar at 15 mm thickness. Thermocol in 20 mm

thickness can be used as a protection board. The cold bitumen (mastic) can be used for fixing the

Thermocol over the Torchshield. Once the Thermocol is fixed, back filling can start in layers.This will allow people to work comfortably as it will create the platform to work as one move

upwards.

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11. WATERPROOFING USING CRYSTALLIZATION

Crystallization is the (natural or artificial) process of formation of

solid crystalsprecipitating from a uniform solution or melt, or more rarely deposited directly

from agas. Crystallization is also a chemical solid-liquid separation technique, in which masstransfer of a solute from the liquid solution to a pure solid crystalline phase occurs.

Process: -

The crystallization process consists of two major events, nucleation and crystal

growth.Nucleation is the step where the solute molecules dispersed in the solvent start to gather into

clusters, on the nanometer scale (elevating solute concentration in a small region), that becomes stable

under the current operating conditions. These stable clusters constitute the nuclei. However when the

clusters are not stable, they redissolve. Therefore, the clusters need to reach a critical size in order to

become stable nuclei. Such critical size is dictated by the operating conditions

(temperature, supersaturation, etc.). It is at the stage of nucleation that the atoms arrange in a defined

and periodic manner that defines the crystal structure — note that "crystal structure" is a special term that

refers to the relative arrangement of the atoms, not the macroscopic properties of the crystal (size and

shape), although those are a result of the internal crystal structure.

The crystal growth is the subsequent growth of the nuclei that succeed in achieving the critical

cluster size. Nucleation and growth continue to occur simultaneously while the supersaturation

exists. Supersaturation is the driving force of the crystallization, hence the rate of nucleation and

growth is driven by the existing supersaturation in the solution. Depending upon the conditions,

either nucleation or growth may be predominant over the other, and as a result, crystals withdifferent sizes and shapes are obtained (control of crystal size and shape constitutes one of the

main challenges in industrial manufacturing, such as for pharmaceuticals). Once the

supersaturation is exhausted, the solid-liquid system reaches equilibrium and the crystallization

is complete, unless the operating conditions are modified from equilibrium so as to supersaturate

the solution again.

http://en.wikipedia.org/wiki/Crystal



http://en.wikipedia.org/wiki/Solution



http://en.wikipedia.org/wiki/Melting



http://en.wikipedia.org/wiki/Deposition_(physics)



http://en.wikipedia.org/wiki/Gas





http://en.wikipedia.org/wiki/Nucleation



http://en.wikipedia.org/wiki/Crystal_growth







http://en.wikipedia.org/wiki/Solvent



http://en.wikipedia.org/wiki/Nanometer



http://en.wikipedia.org/wiki/Temperature



http://en.wikipedia.org/wiki/Supersaturation



http://en.wikipedia.org/wiki/Periodicity



http://en.wikipedia.org/wiki/Crystal_structure



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Many compounds have the ability to crystallize with different crystal structures, a phenomenon

called polymorphism. Each polymorph is in fact a different thermodynamic solid state and

crystal polymorphs of the same compound exhibit different physical properties, such as

dissolution rate, shape (angles between facets and facet growth rates), melting point, etc. For this

reason, polymorphism is of major importance in industrial manufacture of crystalline products.

Description: -

It is a unique chemical treatment for the waterproofing and protection of concrete that is

suitable for the following applications:

Foundation walls

Basement walls

Manholes

Parking decks

Reservoirs

Sewage and water treatment tanks

Tunnels Underground vaults

It can be used on either poured-in-place concrete or concrete block and can be applied to either

the interior or exterior surface with equal results.

Characteristics: -

It waterproofs underground structures from the inside against hydrostatic pressure. By the

process of diffusion and the materials have an affinity with water, the crystalline formation

migrates throughout the pores and capillary tracts of concrete even against strong hydrostatic

pressure. When mixed with water and applied as a cementitious coating, the active chemicalscause a catalytic reaction which generates a nonsoluble crystalline formation of dendritic fibers

within the pores and capillary tracts of concrete. Thus, the concrete itself becomes permanently

sealed against the penetration of water or liquids from any direction.

It protects concrete and reinforcing steel. This treatment is highly resistant to most aggressive

substances, pH 3 - 11 constant contact and pH 2 - 12 periodic contact. By preventing the

intrusion of chemicals, salt water, sewage and other harmful materials, It protects concrete and

reinforcing steel from deterioration and oxidation. The concrete is also protected against spalling,

efflorescence, popouts and other damages caused by weathering, bleeding of the salts and

internal expansion and contraction during the freeze/thaw cycle.

Crystallization permits concrete to breathe. The crystalline formation has fixed-size air spaces so

small that water cannot pass through. It does allow the passage of air and vapor; thus the

concrete is able to breathe and become thoroughly dry, preventing moisture vapor buildup. These

products are nontoxic. They have been approved by NSF International (National Sanitation

Foundation), U.S. Environmental Protection Agency, Agriculture Canada and many other

http://en.wikipedia.org/wiki/Polymorphism






governmental health agencies throughout the world for use on concrete structures that hold

potable water or are in contact with foodstuffs.

Advantages: -

Not just a surface coating – Not dependent upon continuity of membrane for waterproofing

action. Seals hairline cracks upto 0.4 mm.

No surface priming or leveling required.

Cannot puncture, tear or come apart at the seams.

Does not require protection during backfilling or during placement of steel, wire mesh or other

materials.

Can be applied to moist or green concrete

Less costly to apply than most other waterproofing methods.

Types: -

Crystalline waterproofing technology is available in 3 forms: As a coating – For new or existing structures.

As a dry shake material – For new horizontal surfaces.

As an admixture – Included in the concrete mix at the time of batching.

Concentrate: -

Used as a single coating on above- or below grade concrete, or as the first of a 2-coat

application where 2 coats are required. Also used as a Dry-Pac for sealing construction joints and

for repair of cracks, faulty construction joints and honeycombing. Concentrate is the most

chemically potent of the crystalline waterproofing materials.

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Modified: -

Used as a second coat to reinforce Concentrate where 2-coats are required and as a single

coat for exterior damp proofing.

Concentrate DS1 and DS2: -

Dry shake formulations designed for application on fresh horizontal concrete prior tofinishing operations.

Admix: -

Used as an integral waterproofing admixture which is included in the concrete mix at the

time of batching.

Patch’n Plug: -

Fast-setting, nonshrink, high bond strength hydraulic cement compound for concrete

repairs. Stops flowing water in seconds. Patch’n Plug seals cracks and tie holes. It is also used

for the general repair or patching of concrete. Patch’n Plug can be used in conjunction withAdmix to increase the compressive strength and bond strength of existing concrete.

Acrylic Admix: -

An acrylic polymer formulation specifically designed for use as an admix to fortify

Portland cement mixes. Acrylic Admix increases hardness, durability, bonding capability and

chemical resistance.

Gamma-Cure: -

Can be used as an alternative to water curing for certain applications.

Installation

Surface Preparation: -

Concrete surfaces to be treated must be clean and free of laitance, dirt, films, paint, coatings or

other foreign matter.

Surfaces must also have an open capillary system so as to provide tooth and suction for

treatment. If surfaces are too smooth, the concrete should be acid etched, lightly sandblasted or

water blasted.

Structural defects such as cracks, faulty construction joints and honeycombing should be routed

out to sound concrete and repaired.

Horizontal surfaces should have a rough wood float or broom finish. On fresh horizontal

concrete Concentrate DS1 or DS2 powder can be power troweled into the surface while it is still

in plastic state.

Wetting Concrete: -

Prior to the application, concrete surfaces must be thoroughly wetted with clean

water to control surface suction, aid the proper curing of the treatment and ensure the growth of



the crystalline formation deep within the pores of the concrete. Excess surface water should be

removed before the application.

Methods: -

To mix the product for slurry coat application, the Xypex powder is mixed with

clean water to a creamy consistency in the following proportions by volume:

Mixing for Brush Application: -

Mix 5 parts powder to 2 parts of water (0.8 kg/m2).

Mix 3 parts powder to 1 part of water (1.0 kg/m2).

Mixing for Spray Application: -

Mix 5 parts powder to 3 parts water (0.8 kg/m2). The mix may vary with equipment type.

Mixing for Dry – Pac: -

Mix 6 parts Concentrate powder with 1 part clean water by volume. Do not mix too wet, otherwise, mix may crack and spall at it dries.

Application: -

The treatment should be applied with a semi-stiff br istle brush, a janitor’s broom for large

horizontal applications, or with specialized spray equipment. The treatment must be uniformly

applied under the conditions and quantities specified. One coat should have a thickness of 1/16"

(1.6 mm). When a second coat is required, it should be applied after the first coat has reached an

initial set but is still green (less than 48 hours). Light pre-watering between coats may be

required due to drying. The treatment cannot be applied in rain or during freezing conditions.

Spray Application of Crystalline

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Brush Application of Crystalline

Curing: - A misty for spray of water must be used for curing the treatment.

Curing must begin as soon as the coating has hardened sufficiently so that it is not damaged by a

fine spray.

Under most conditions, it is sufficient to spray the material treated surfaces 3 times a day for 2 –

3 days.

In hot, dry weather, spraying may be required more frequently.

During the curing period, the treatment must be protected from rainfall, frost and puddling of

water.

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WATERPROOFING MATERIALS

1. PIDIPROOF LW (Specifications conforms to IS-2645) - Its an Integral liquid waterproofing

compound for plaster and concrete.

Features / Benefits

Being a liquid, dispersible in concrete/mortar mixes. Makes concrete/mortar more cohesive

Increases durability, by increase in impermeability.

Economical in application

Does not affect the setting time and strength.

Reduces shrinkage cracks in plaster and concrete

Shelf life : 1 year

Typical applications

For waterproofing of concrete and sand-cement mortar used in basements, roof slabs and

screeds, water retaining structures, external plastering,

Technical information

Base : Fatty acid

Total solid content : 13+0.5%

pH : High alkali

Dosage/Coverage

200 ml per 50 kg bag of cement. Just add gauging water that is to be mixed with

mortar/concrete.

2. TONIC (Cement additive)

Features / Benefits

Delays corrosion by minimising chloride penetration

Increases workability for easy placement.

Increases strength and durability, by reducing water cement ratio.

Produces waterproof concrete/mortar by blocking capillaries/pores in the concrete

Shelf life : 1 year

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Dr. Fixit TONIC shall be added to all types of concrete and mortar to achieve water proof

and durable concrete/mortar e.g. RCC column, beam, slab, water retaining structures, external

plastering, screeds, water tanks, sumps and drains, etc.


Base : Polymer modified Fatty acid Total solid content : 13.50+0.5%

Specific gravity: 1.05+0.02

pH : High alkali

Dosage/Coverage

200 ml per 50 kg bag of cement. Just add to gauging water that is to be mixed with

mortar/concrete.

3. PIDIFIN 2K(Certification by CFTRI, Mysore, for Portable water contact) – It is brush applied

waterproofing coating for balconies, small terraces, wet areas & ledges

Features / Benefits

Provides excellent impermeable coating.

Good adhesion with cementaitious surfaces

Applied for positive & negative sides of waterproofing

Flexible enough to take care of minor cracks in concrete & plaster.

Durable and economical

Available in pre-packed, ready-to-use containers.

Shelf life : 6 months


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Bathrooms and wet areas

Small terraces upto 1000 sq.ft.

Internal walls for prevention from seepage due to rain lash

Small water tanks interior surfaces (upto 30,000 ltrs. capacity)


Appearance : Grey powder + white liquid

Mix ratio (Powder:Liquid) = 2:1(by weight)

1.5:1(by volume)

Pot life at 30 degree Celsius : Approx. 30 mins.

Application temp : Between 10-30 degree Celsius

Dosage/Coverage

6-7 sq.ft./kg for 2 coats for total minimum thickness of 1 mm approximately. For

protection against physical damage, a mortar screed of 15-25 mm thickness may be provided.



4. PIDICRETE URP(SBR Latex for waterproofing and repairs)

Features / Benefits

White liquid, easily brush applied.

Useful as waterproofing coat.

Useful as a bonding agent between old and new concrete surfaces. Excellent as a cement modifier.

Repair mortar modified with Dr.FIXIT Pidicrete URP suitable for repairing of RCC beams,

columns, slabs and other RCC members

Shelf life : 1 year


Waterproofing of terraces, toilets, edge, masonary walls, sloping RCC roofs etc.

Repairs to RCC members

Waterproofing mortars/concretes.

As an additive in plasters at 5-6% by weight of cement content


Total active solid content: 34+2%

pH : 8-9

Pot life : 30-45 minutes, when mixed with cement at 30 degree celsius

Dosage/Coverage

20-22 sq.ft./kg for 2 coats(URP + cement in proportion 1:1.5)

5. SUPER LATEX (SBR Latex for waterproofing and repairs)

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Features / Benefits

Excellent coverage 70-80 sq.ft./kg in 2 coats, hence economical

Less material wastage: material does not fall back/rebound, when used as bonding agent.

High bond strength.

Prevents leakage and dampness.

Enhances strength of a repair mortar & provides durability.

Shelf life : 1 year


As a bond coat : Plaster to plaster, Concrete to concrete, for plaster over brick masonry.

As waterproof repair plaster.

Crack repair : Plaster cracks more than 5mm in gaps developed between masonry and RCC

members

As coating for prevention of corrosion in rebars.

Efflorescence(salt petre/damp surfaces)


Type : Styrene butadiene rubber polymer liquid Colour : white

Storage condition : free from frost

Active solid content : 44+1%

Dosage/Coverage

Mix (S.Latex:Water:Cement) = 1:4:7, 70-80 sq.ft./kg for 2 coats as a waterproof coating.

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water proofing-residential buildings

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