Thursday, July 26, 2018

Waterproofing in Construction Industry

     In building construction, a structure needs waterproofing since concrete itself will not be watertight on its own (but note concrete is easily waterproofed with additives). 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, EPDM 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. In the UK these membranes are rarely allowed below ground below the water table.

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 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.

Damp proofing in Residential Buildings

Water Proofing for Roofs





Case Study in brief

We have narrated in brief about the system of waterproofing, its wide classification and also the latest waterproofing methods in the present trend. As for as our assignment is concern, we took a case study of an industrial building (220KV Power station- Dubai) where we can see the conventional method of waterproofing works being carried out for substructure and roof slab. 

Classification of waterproofing            Waterproofing shall be classified under the following categories,

Classification based on structureClassification based on technology

Classification based on Structure



Based on structure, it is classified as

Sub- structural water proofing (e.g.: below ground level)Super-structural water proofing (e.g.: Roof)



Sub- structural water proofing: There are quite lot many ways that are followed on structural basement waterproofing works and some of the common and unique techniques of waterproofing using specific branded compounds are as follows.

HOW TO WATERPROOF BASEMENT









Compound Used: Ames'® Super Primer, Vapor Barrier

Brand name        : AMES1. Surface preparationAlways run a test patch first in an inconspicuous area, to ensure that proper adhesion and drying occurs and the product works to your satisfaction. Careful and complete preparation will ensure the best results, and contribute to the life of the coating. The wall surface must be clean, dry, and free of loose material. Loose or peeling paint should be removed with a wire brush, and rough wood surfaces sanded. Do not apply Vapor-Barrier™ over wet, loose, or crumbling concrete. Repair the concrete, and allow curing. Mildew may be removed with a power washer. Fill all joints or cracks wider than 1/8 inch with a Blue Max trowel-grade coating & filler. Follow seam taping instructions. Mask all sensitive areas before starting.2. Prime the surface with Ames' Super PrimerIt is important to seam tape all joints and cracks to avoid future cracking and leaking. Apply around flashings, windows and cracks in the walls. Refer to Ames' Seam Tape label for application instructions. Do not use fiberglass or asphalt impregnated seam tape.Super Primer penetrates into the concrete. It is pearlescent blue as it is being applied, drying to a clear, slightly tacky surface. This process begins the waterproofing. Apply at a rate of 1 gallon per 100 square feet (estimated).

                Super Primer is drying almost as fast as it can be sprayed onto the surface.3. Apply Ames' Vapor-BarrierApply at least 2 coats of Vapor-Barrier, our waterborne, liquid rubber, elastomeric coating. At this point the surface should be impenetrable to water. All minor cracks and crevices will be sealed. Apply at a rate of 2 gallons per 100 square feet. Recommended milage is 20 to 35 mils (or the thickness of a dime or quarter). Drying time will be approximately 30 to 60 minutes on warm days with sun contact.     This application can be used on: foundations, bearing walls, cisterns or water storage tanks, and other concrete surfaces. Vapor-Barrier is potable water compliant.Clean-up, Storage, Disposal and Thinning Clean up tools and small spills with water. Store unused product in its original can, tightly sealed at 45 to 85 degree F. Dispose of this product in accordance with state, federal, and local requirements. May thin up to 10% with water.                                       Weather & Drying Guidelines Ames' Coatings are best applied between 40 to 90 degrees F. on warm dry surfaces. Apply when the streets are dry, the sun is in the sky, and no inclement weather is forecast. Dries in 1-2 hours, depending on thickness of application and weather; and cures in 24 hours. Low temperatures, high humidity, and evening or morning dew will require increased drying/curing time.Estimated Coverage: Super Primer: apply at a rate of 1 gallon per 100 square feet (estimated). Vapor Barrier: Apply at a rate of 2 gallons per 100 square feet.HOW TO SEAL OR WATERPROOF THE LEAKING BASEMENT?1. Surface Preparation Read all label instructions before beginning. Always run a test patch first in an inconspicuous area, to ensure that proper adhesion and drying occurs and the product works to your satisfaction.Careful and complete preparation will ensure the best results and contribute to the life of the coating. The wall surface must be clean, dry, and free of moss and loose material. Loose or peeling paint should be removed with a wire brush and rough wood surfaces sanded. Concrete surfaces may be prepared by using a disc grinder and carborundum disc or sand blasting. Do not apply over wet, loose or crumbling concrete. Repair the concrete and allow to cure completely. Mildew may be removed with a power washing. New concrete should be allowed to cure for at least 30 days prior to application of this product. Fill all joints or cracks wider than 1/8 inch with Blue Max™ trowel grade coating and filler. Follow all seam-taping instructions. Mask all sensitive areas before starting.Be sure the concrete is dry before beginning. Drying the basement wall out completely before proceeding will be necessary. Use of a propane space heater as needed may be necessary to complete this task. Construction space heaters may be rented or purchased. Allow proper ventilation. Primer penetration and curing will be dependent on a dry surface.

2. Prime the Surface and Seamtape Joints and CracksPrime the surface with Ames' Blue Max Liquid Rubber. It is important to seam tape all joints and cracks to avoid future cracking and leaking. Our Peel & Stick Seam Tape is a self-adhesive, high-strength, contouring seam tape that is easy to apply. For the best adhesion prime all surfaces with Ames'® Blue Max before applying seam tape. Refer to Ames' Seam Tape application guide for application instructions. Do not use fiberglass or asphalt impregnated seam tape as a substitute. Use only Ames' Tapes. Once the seam tape has been placed over the primer it will be next to impossible to remove. The seamtape is pliable, so it is easy to shape with your fingers, even to corners. Warning! Do not uses asphalt sealers. They do not really water proof. Asphalt will simply float over damp surfaces. When the petroleum evaporates the owner is eventually left with nothing but prehistoric animal pigment.3. Application Ames' Block & Wall™ Liquid Rubber or Blue Max may be applied by brush, roller or sprayer. Shake or stir Block & Wall Liquid Rubber prior to use. Apply a minimum of one gallon per 100 sq. ft. per coat. Two coats minimum, three to four is superior. The application must be applied in a continuous, unbroken seal of a minimum dry thickness of no less than 30 mils (the thickness of a dime) over the entire surface.Good: Prime the concrete surface with one or two coats of Blue Max and then apply one or more coats of Ames' Block and Wall Liquid Rubber coating at a rate of one or two gallons/per/100 square feet. One or two coats of Ames' Block & Wall Liquid Rubber or Blue Max will cover and waterproof in most cases. Use all the product estimated for the job in order to achieve the proper millage.

Better: First prime with Blue Max over the concrete. Then apply two to three coats or three gallons per 100 square feet of Block & Wall Liquid Rubber or Blue Max. Use the entire product to achieve the proper millage.

Best: This type of heavy-duty application is normally used when applied on a below grade surface where a severe waterproofing situation might exist. This procedure is generally used on new commercial building applications where long-term heavy-duty applications might be required. The very best product application is five gallons per 100 sq. ft. or three to five coat application systems necessary for long term waterproofing. In this application fabric can be applied over most smooth surfaces and is generally embedded in the second layer of the liquid rubber. The fabric becomes saturated and is sandwiched in the coating and allowed to dry for additional reinforcement. It applies like fiberglass. The fabric is polyester and shapes like fiberglass and will never rot or deteriorate. This application is nearly impervious to water penetration when properly done and expected to last up to twenty plus years. It can also be applied to concrete or wood surfaces such as concrete roofs where bare concrete has begun to deteriorate. Concrete roofs are often in need of special attention especially in the tropics when rains are heavy and concrete is decomposing. Otherwise this application is usually not necessary unless the surface is in danger of deteriorating since these coatings are extremely elastic. On above grade applications apply two to three coats of Blue Max followed by two coats (2 gallons per 100 square feet) of Ames' Block & Wall waterproofing paint or Ames' Paint and Prime Paint and Prime is tintable.

Weather & Drying Guidelines Ames' Coatings are best applied between 40 to 90 degrees F. on warm dry surfaces. Apply when the streets are dry, the sun is in the sky, and no inclement weather is forecast. Dries in 1-2 hours, depending on thickness of application and weather; and cures in 24 hours. Low temperatures, high humidity, and evening or morning dew will require increased drying/curing time.

BASEMENT WATERPROOFING USING PIPELINE TECHNIQUESWe were called out to provide a solution for a water problem in a basement. The basement was not properly tanked during the construction phase. None tanking can result in major waterproofing problems in the future - Our client experienced between 10mm-30mm of water ponding on the entire floor of the basement. A permanent water pump was installed to pump out the water.The builders had penetrated an unforeseen but very real underground 'river' during construction. Water penetrated from both the floor and the construction joints between the walls of the basement.

                                  Diagram of basement showing level of water
                                  Diagram showing construction joint in a basementHow to properly tank a basement retaining wall?Step One Excavate around the basement down to foundation level. This is best done during construction phase when no excavation is needed.

Step twoApply generous amounts of Bitumen Primer by means of block brush or roller to all the areas that will receive the torch on membrane

Step threeHeat fuses the torch on membrane to the primed areas.

Torching is quite tricky and should only really be done by persons who have experience in this.

Step fourConnect the pieces of flow pipe and wrap in bedim cloth

Flow pipe is a pipe with holes in it.

The pipe allows water to pass into it and flow away to a storm water outlet.

Bedim cloth is a geo textile that act likes a filter to stop sand and other objects entering the pipe

Tip: It is important to get the levels of the flow pipe falling correctly. It would be best to consult a drainage expert on this. Some council regulations demand that plans be approved for drainage systems

Step fiveSurround the flow pipe with 19mm builder stone.

The stone acts as the first filter

Step sixBack fill with clean sand

How to waterproof concrete roofs?Waterproofing concrete with roof coatings is an important task on concrete structures for roof repair and preservation. Many roofs throughout the world are constructed using poured concrete. These structures are usually made with reinforced steel. They are inexpensive but require a great deal of maintenance to keep them from leaking since they shift, move, and dissolve easily. The problem with concrete is that it IS concrete. Concrete is made up from several ingredients including calcium carbonate and sand. Calcium Carbonate is a plentiful substance that comes from the dead skeletons of sea life. These plentiful substances dissolve quite easily in very wet environments unless they are protected.

The Ames specializes in the making of specialty rubber and plastic coatings that extend the life of concrete. These products stretch with the concrete and form a waterproof membrane. Unfortunately, untreated concrete cracks and dissolves in many geographic areas where there is a great deal of rain. In the wintertime, water leaks into the untreated cracks and freezes and expands substantially damaging your concrete building.

Before beginning any project, read all instruction labels. Always run a test patch first in an inconspicuous area, to ensure that proper adhesion and drying occurs and the product works to your satisfaction

Usually a concrete structure is composed of four walls of poured concrete and a poured concrete roof. Walls and parapet walls, both outside and inside, over the roof need to be water proofed. Both outside walls and inside walls should always be considered to be a part of your waterproofing tasks. The building should be thought of as a total building envelope. If you have stucco on the outside of the building, use Ames “Super Primer” and then “Paint & Prime®” to waterproof the stucco or concrete surface.

PREPARE THE SURFACEHow to fix flat roofs or concrete roofs with “roof coatings” is really a simple process even for the “do it yourselfer”. The first thing you should do is to power wash the entire surface area of the roof, which will remove most of the loose material. Use caution, so as not to damage any interior areas due to roof leakage that are inside the building. In certain situations, a shot-blaster may be needed to roughen the surface. In addition, it might be a good idea to fill any large cracks and crevices with mortar.

PRIME THE SURFACEAfter preparing the surface you will need to prime the roof with Ames Pure Acrylic Plastic primer, “Super Primer”. Super Primer will dry rapidly and will flow into the cracks and crevices of the concrete rooftop. It will bond to the concrete with remarkable adhesion. Super Primer has an affinity for concrete and it actually glues together and strengthens old concrete surfaces. Read all instruction labels before beginning. Always run a test patch first in an inconspicuous area, to ensure that proper adhesion and drying occurs and the product works to your satisfaction.

SEAM TAPENext, seam tape all remaining cracks larger than one-eighth of an inch. Seam tape with “Ames Peel & Stick” Seam tape. This tape comes in 2 inch, 4 inch, and 6 inch widths by 50-foot rolls. This rubber tape contours easily to the surface and will stick with the most remarkable adhesion to the primed surface. The seam tape will be difficult to remove from here on out.

TOPCOAT OVER THE SURFACEApply at least two gallons per 100 sq. ft. of “Super Elasto-Barrier” or similar Ame's product. Finally, apply two to three gallons per 100 sq. ft. of Ames Maximum Stretch elastomeric acrylic plastic coating. Super Primer, Seam Tape, Super Elasto Barrier, and “Maximum-Stretch” are an unbeatable combination for concrete roofs.





DRAINAGE

Proper drainage is also an important factor on concrete roofs. With this application, you will be substantially strengthening the concrete with the pure acrylic plastic Super Primer. Followed by the rubber “Super Elasto-Barrier”. Be sure to apply seam tape where the vertical and horizontal concrete joints meet at the parapet roof and wall joints. The parapet wall and cap also need to be water proofed. This combination of coatings, as well as the outside of the parapet wall, should be waterproofed with Ames “Paint & Prime”.
ROOF DECKS

If the surface is a roof deck application and you wish to walk on your roof, then you can apply Ames “Safe-T- Deck” non-skid durable plastic paint as your final coat. This product comes in a variety of colors. Lighter colors are best for areas in high heat. Dark colors in the northern hemispheres.
The drawing below describes a basic product application. 
CONCRETE ROOF
1. Always run a test patch first to ensure that proper adhesion and drying occurs and the product works to your satisfaction. The whole concrete roof is cleaned and power-washed, then flood coated with Ames' Super Primer, pure acrylic primer.
2. Repair large holes with concrete patch. Seam tape large cracks with Ames' Peel & Stick adhesive seam tape.
3. For best results, topcoat the concrete roof surface with Ames' Super Elasto-Barrier and Maximum-stretch.
CONCRETE WALLS
1. Always run a test patch first to ensure that proper adhesion and drying occurs and the product works to your satisfaction. The whole concrete wall is cleaned and power-washed.
2. Repair large holes with concrete patch. Seam tape large cracks with Ames' Peel & Stick adhesive seam tape.
3. For best results, topcoat the concrete wall surface with Ames' Super Primer and Ames' Paint & Prime All-In-One premium acrylic paint.
Seal and Waterproof an Existing Chimney

 Always run a test patch first in an inconspicuous area, to ensure that proper adhesion and drying <![if !vml]><![endif]>occurs and the product works to your satisfaction.
<![if !vml]><![endif]>
Clean and Prepare the Surface

Clean the surface, and scrape or remove loose debris before starting your project. Be sure surfaces are clean and dry before seam taping or the coating application.
 Seam Taping

<![if !vml]><![endif]>The purpose of seam taping is to provide reinforcement over areas prone to splitting, such as seams, cracks or joints, and create a “bridge” that ties the surfaces together so water cannot seep through. Peel & Stick Seam Tape is self-adhesive. Measure out the length of Seam Tape needed and press into place.
 Apply Super Elasto-Barrier To The Chimney

Apply Ames' Super Elasto-Barrier, a waterborne liquid dual-rubber Coating as a primer over the seam tape and the rest of the chimney surface. Super Elasto-Barrier is up to 1000% Elastic. It may <![if !vml]><![endif]>be brushed rolled or sprayed.
Topcoat with Ames Coatings

A topcoat of Ames' Maximum-Stretch or other Ames coating may be applied to the chimney.
Weather & Drying Guidelines

Ames Coatings are best applied between 40 to 90 degrees F. on warm dry surfaces. Apply when the streets are dry, the sun is in the sky, and no inclement weather is forecast. Dries in 1-2 hours, depending on thickness of application and weather, and cures in 24 hours.
Low temperatures, high humidity, and evening and morning dew will require increased drying/curing time.
Estimated Coverage

Standard product coverage on a smooth surface is 100 sq. ft. per gallon (est. 10ml). More than one coat recommended. More coats equal longer life.

Waterproofing for Metal Roofs

Ames industrial metal roof coatings are your first choice in metal roof waterproofing and metal roof repair. Ames premium metal roof coatings are formulated especially for commercial and residential metal roofs, recreational Vehicles (RV's), mobile homes, steel roofs and aluminum roofs. Ames coatings are water base, non-toxic, VOC-free and have low odor. They are easy to apply and are water clean-up.
<![if !supportLists]>v <![endif]>Storm Damage
<![if !supportLists]>v <![endif]>Leaking Metal Roofs
<![if !supportLists]>v <![endif]>Rusty Metal
<![if !supportLists]>v <![endif]>Oxidized Aluminum


1. Surface Preparation

The roof must be dry. Remove loose dirt, flaking rust, and debris from the roof surface. Refasten any screws or nails that may have worked loose. Be sure surfaces are clean and dry before the coating application. Caulk all cracks greater than 1/8” wide with Blue Max™ trowel-grade coating and filler.
2. Seam Tape & Prime the Roof Surface

Prime with 1-3 coats of Super Elasto-Barrier™, Maximum-Stretch™ or Iron Coat™ until the roof surface is smooth and sealed. Let cure so that it's dry to the touch. Surfaces with joints, cracks, flashings, vents, parapet wall flashings or where two unlike surfaces come together, require Ames’® Peel & Stick Seam Tape (PS250, PS450, PS650) to provide some additional strength and reinforcement.


1. Peel off the backing
2. Line tape up with seam
3. Press firmly into place.
3. Pour it out and Paint it on

Apply coating as needed for a durable, hard shell, thermo-reflective surface.
Clean up, Storage, Disposal and Thinning

Clean up tools and small spills with water. Store unused product in its original can, tightly sealed at 45 to 85 degree F. Dispose of this product in accordance with state and federal and local requirements. Thin with water up to 10%.
Weather and Drying Guidelines

Best results when applied between 40 to 90 degrees F on warm dry surfaces. Apply when the streets are dry, the sun is in the sky and no inclement weather is forecast. Dries in 1-2 hours, depending on thickness of application and weather; cures in 24 hours. Low temperatures, high humidity and evening and morning dew will require increased drying/curing time.
Estimated Coverage

Standard product coverage on a smooth surface is 100 sq. ft. per gallon per coat (est. 10ml). More than one coat recommended. More coats equal longer life.
A Suggested Metal Roof Application



Apply Roof Fabric

For use on:
<![if !supportLists]>v  <![endif]>Smooth tar roofs
<![if !supportLists]>v  <![endif]>Roof decks
Advantages:
<![if !supportLists]>v  <![endif]>Lasts longer
<![if !supportLists]>v  <![endif]>Added strength
<![if !supportLists]>v  <![endif]>Keeps the roof from splitting
<![if !supportLists]>v  <![endif]>Reduces movement
Ames'® Polyester Contouring Roof Fabric adds substantial strength to the coating of roof surfaces. It reinforces the coating to resist ripping and tearing. Roof Fabric increases penetration resistance. It may be cut to different widths for specialized jobs. Roof Fabric is especially useful for roof decks and gutter areas and may be used over plywood, concrete, metal and many other surfaces.


Do-It-Yourself in three easy steps

Roof Fabric is normally set with Super Elasto-Barrier , but in special cases may be set with Maximum-Stretch, Snow Seal®, or Iron Coat. Surface preparation is everything. Prepare the roof by removing dirt, moss and other debris. Power wash and let dry thoroughly. Prime the roof smooth and apply seam tape and Super Elasto-Barrier to all joints and seams.
Step one: Starting at one end pour out a liberal amount of coating onto the surface. Use a push broom or roller to spread the coating out in a path slightly wider than the roof fabric being used. Roll the fabric into the wet coating until the coating comes up through the fabric and totally saturates it. This is best done by laying the roll of fabric down and pushing it forward into the wet coating with the push broom or roller while the excess coating comes up through the fabric. Avoid folds and wrinkles. Use a liberal amount of coating. The fabric will absorb almost two gallons per 100 square feet.
Step two: With the roller or push broom, pull the excess coating off to the side in preparation for laying the next row of fabric. Use the lap line on the fabric roll as a guide. One may butt or overlap the fabric. If you choose to overlap the fabric, overlap its entire length by three to four inches. Overlap may leave a seam. Repeat this process until the entire surface is completely covered with fabric. Allow to dry completely 24 to 48 hours.
Step three: To complete the roof fabric application process, apply an additional coat over the surface to completely seal and fill all remaining pinhole openings in the fabric. The goal is to have all pinholes filled and no less than 30 miles of thickness (a dime). The coating is best applied by pouring out and spreading. Topcoat with Ames' Maximum-Stretch, Safe-T-Deck or Snow Seal according to label specifications. Allow proper drying between coats.


Classification based on Technology

Nano Technology in Water Proofing:

Abstract:

Water intrusion in building materials has been a problem for the last 1000 years. Regrettably, this problem was never fully addressed due to a lack of understanding on a Nano scale. Fortunately, new developments in science and technology have incorporated the use of Nano technology to produce eco-friendly, Organo-Silicon products that can render most cementitious materials hydrophobic for cycles of 20 to 30 years or more at a very economical cost.
Introduction:

Building materials are known to have water seepage and water leaks due to inherent porosity and micro cracks. Water repellency can be achieved through treatments, which are expected to render cementitious materials impervious to water. Over the last 50 years, a significant amount of technology has been developed utilizing various methodologies. One of the most common methods utilized a blend of basic polymeric chemistry and other materials to create products that are resistant to water intrusion.


Water Repellents:

One of the primary objectives of water repellents is to maintain and preserve aesthetics, by protecting cementitious substrates from water related issues such as:
                       
<![if !supportLists]>v <![endif]>Paint peel-off

<![if !supportLists]>v <![endif]>Paint blisters

<![if !supportLists]>v <![endif]>Fungus

<![if !supportLists]>v <![endif]>Mold & Mildew

<![if !supportLists]>v <![endif]>Efflorescence

In addition to aesthetic preservation, water repellents address more serious structural issues such loss of structural strength of concrete building materials due to ASR (alkali silica reaction), acid rain, and sulphate attack. Water repellents can also prevent chloride penetration, which often results in the corrosion of the reinforced steel bars.
Water related problems

– Most cementitious building materials are very porous and have surface hydroxyl groups. These hydroxyl groups attract water because of the hydrophilic nature and similarity with the structure of water.  Therefore, most cementitious building materials easily absorb water into the pores when water is present. The size of the water molecule is 0.18 nm (nanometer = 10-9 meter, i.e. .00018 microns).  The pore size in most cementitious building
materials range from 5 to 200 nm.  Most pollutants such as acids, chlorides, and sulphates range between 1 to 2 nm. Even the most dense concrete and stones and have pore sizes much larger than water which enable both water and other damaging chemicals to easily penetrate the pore structure of these materials.
As the world has started to pay more attention to aesthetics, the building industry has begun to rely on more often on water repellents as the primary mechanism to maintain and preserve the clean look of new buildings. As a result of this demand, many products are currently commercially available, however, it is important to recognize that the essential functions that these water repellents should address are:
<![if !supportLists]>v <![endif]>Resistance to water intrusion

<![if !supportLists]>v <![endif]>Prevention of water-soluble salts, particularly chloride salts

<![if !supportLists]>v <![endif]>Penetration of repellent treatment to a measurable depth

<![if !supportLists]>v <![endif]>Will not stain surface areas

<![if !supportLists]>v <![endif]>Long-term stability in an alkaline environment

<![if !supportLists]>v <![endif]>Low environmental and health risk

<![if !supportLists]>v <![endif]>UV stability (20+ years)

There are 2 classes of waterproofing products:
1. Film Formers
2. Penetrants / Repellents
Film Formers:

The economics and the ease of application have led to widespread use of film forming water repellents. Products like acrylic paint and silicon polymers are commonly used in the world for waterproofing applications.  These film formers have a particle size greater than 100 nm, which will not allow them to penetrate inside the pores of the building materials but instead form a film covering and protecting the surface from water absorption.  Generally, these polymer films are hydrophobic but they need to be continuous and defect-free and also must be UV resistant.  It is found that during application, ensuring a continuous film on rough surfaces is difficult to achieve which leads to weak points in the film.  Most typical polymer films tend to break down under UV exposure leading to cracking of the films in 2 to 5 year. This leads to failure in terms of losing the hydrophobic water resistant features of the film.
Penetrants / Repellents:

Most penetrants are solvent based, soluble monomeric materials less than 6 m in size which can easily penetrate inside the pores and sub-branches of the pores.  There are two types of penetrants: (i) non reactive and (ii) reactive. 
Non-reactive penetrants are oils and other low viscosity hydrophobic materials, which coat the pores of the substrates and provide water repellency.  However, these types of materials are also biodegradable and lose their hydrophobic characteristics within a year.  Additionally, these products also provide food for mold or fungus growth on the substrate surfaces and into the pores.
Reactive penetrants chemically react with the substrate and provide molecular level hydrophobic protection 3 to 5 mm deep into the substrate.  Therefore, these types of water repellent products provide protection for a long period.  Additionally, the product is bound chemically on a molecular level to the substrate. As a result weathering (UV exposure) and natural abrasion have little impact on the ultimate waterproofing characteristics.
Silanes and Silane / Siloxanes are recognized as a new class of water repellent technology that uses two methods to suppress water intrusion.
Solvent based silane water repellent compounds have been proven to provide long lasting performance and are used widely in USA and Europe.  The two alkyl silanes most often used for waterproofing are: (i) isobutyltrialkoxysilane (ii) n-octyltrialkoxysilane.
The silanes used with water repellent technologies are monomeric materials are known as alkylalkoxysilane. Alkylalkoxysilane has two types of groups (a) alkyl group, R’ and (b) alkoxy groups, (OR) which are reactive with most cementitious building materials.
Alkyl Group
O           R
R’          Si      O      R   
   Alkoxy Groups
O           R


Organosilicon Waterproofing Products:



Alkylalkoxysilane

Most cementitious building materials contain hydroxyl (OH) groups.  These OH groups can chemically react with alkoxy groups of Silane to form permanent siloxane bonds with the substrate.  The alkyl group R’ provides hydrophobicity (water repellency) on the surface. Therefore, these types of products impart water repellency by modifying surface characteristics from hydrophilic to hydrophobic.
Although solvent based silanes can provide superior performance, usage is often limited because of its high cost, flammability and toxicity related to the solvent content limiting its usage to more critical structures. Recently, Zydex Industries in India developed a water repellent technology known as Zycosil, which provides the four most desired properties (Eco Friendly, Easy to apply, Long lasting, Affordable) based on nano technology. Zycosil provides molecular level hydrophobicity to inorganic substrate and is eco-friendly because it is applied in water solution and the VOC per applied square meter is less than 20% of solvent based silanes. The product is based on organosilane chemistry; hence it reacts with the inorganic substrate surface and provides service life of 20 to 30 years service.
Eco-Friendly Water Based Nano Technology – Zycosil: Zycosil is an organosilane product, which forms a particle size of 4-6 m in water and penetrates deep into the building material pores (3-5 mm depth).  The product becomes part of the building material and makes it highly water repellent.
The product has shown 4 major attributes:


<![if !supportLists]>v <![endif]>ZYCOSIL has a long expected life of 20 to 30 years, confirmed by weathering test data conducted with ASTM test methods.

<![if !supportLists]>v <![endif]>ZYCOSIL is diluted 1:10 or more with tap water, and emits an extremely small amount of organic solvent into the atmosphere, making it eco-friendly and non flammable.

<![if !supportLists]>v <![endif]>ZYCOSIL can be applied by brush, spray or roller techniques, making it user friendly. ZYCOSIL provides water repellency at a material cost lower than existing technology and products, which can give a similar initial performance.

Zycosil Treated Substrate Testing:



Rilem Test:

The Rilem tube was affixed on the substrate surface.  Water was filled up to the 5ml mark.  The drop in water level was observed over a 20-minute period.  The hydraulic pressure generated on the surface was equivalent to 140 Km/hr wind driven rain.
Untreated:                                
The water level did not drop for a 24 hour period on the Zycosil treated cement block. The water level of untreated cement blocks dropped to about the 2.5 ml mark after 20 minutes.  The Rilem test is also used for water absorption rate.  The absorption rate is determined and compared with the untreated samples.
Treated:

Zycosil treated samples (brick, concrete, cement sheet, plaster, stone, etc.) reduced water absorption rates by over 99 %.
Accelerated weathering:

Weathering Cycle: The UV exposure was set according to ASTM G-154 (21 hours), followed by rain showers (1 hour) and drying at 110C (2 hours).
The Zycosil treated samples (Concrete blocks, Bricks, Plaster, Sand stone, and Cement Sheet) have undergone over 80 cycles.
All the Samples retained over 98 % of water repellency, after 80 cycles.
Water uptake test:

This test was carried out according to ASTM 6489 method. The Zycosil treated samples were weighed to the nearest 0.01 grams, and then placed with treated or exposed surface only, in a tank containing several inches of tap water for a period of 24 hours.  The samples were then removed from the water, towel dried and reweighed.  The initial and final weights were used to calculate the 24-Hour Treated Water uptake values.  These values were compared with the untreated samples.
Zycosil treated samples showed over 90 % reduction in water uptake of water.




CASE STUDY :

A) Method Statement for roof waterproofing works:
1.Scope Of Work:
      This method statement covers the roof water proofing system intended to be used for the above mentioned case study project.
2.Approved Applicator:
M/s Water Seal Co.LLC.Abudhabi
3.Materials Used :
<![if !supportLists]>v <![endif]>Masterseal 420:Bitumen Emulsion primer from M/S BASF
<![if !supportLists]>v <![endif]>DAREX AE4: Foaming agent for foam concrete from M/S Grace
<![if !supportLists]>v <![endif]>IMI Primer: Bituminous primer from M/S IMI
<![if !supportLists]>v <![endif]>4mm thick EKOGUARD: APP Modified bitumen membrane from M/S IMI
<![if !supportLists]>v <![endif]>ESSCOFOAM 35-6,50mm thick insulation board from M/S ESSCOFOAM
<![if !supportLists]>v <![endif]>A281 Geotextile Fabric: Geo textile separation layer from M/s ALIAF Industries
<![if !supportLists]>v <![endif]>Roof tiles: 500x500x50 mm thick cement tiles from M/S Terrazzo
SURFACE PREPARATION:

The surface shall be properly prepared by brushing, clearing and leaving the surface free from dust, dirt, grease, loose or projecting particles of mortar etc. The installation of all the pipes, cables and fixing of rain water outlets shall be done prior to waterproofing. All the corners and penetrations shall have cement sand angle fillets.


APPLICATION OF COLD APPLIED COATING:
<![if !supportLists]>v <![endif]>After surface is thoroughly cleaned, first coat of approved masterseal 420, and shall be applied at a rate of one litre/sq.m.
<![if !supportLists]>v <![endif]>Next day, 2nd coat shall be applied at a rate of one litre/sq.m.But in the opposite direction i.e 2nd coat is applied at right angle to first coat.
<![if !supportLists]>v <![endif]>The coating shall be allowed to dry for minimum of 2 days.
FOAM CONCRETING:

After the application of masterseal 420 and drying, minimum 50mm thick foam concrete shall be laid as per the mix design already submitted. The initial setting time of foam concrete under present weather is 18 to 24 hrs. Curing for 3 days is required.
APPLICATION OF PRIMER:

After curing of foam concrete is completed, all the areas where the membrane has to be laid shall receive 2 coats of approved IMI primer applied by brush or roller at the rate of 250gm/sq.m.
Primer shall be allowed to dry fully before membrane application.
Drying of primer : 12-24 hrs, depending up on weather conditions
APPLICATION OF WATERPROOFING MEMBRANE:

Approved waterproofing membrane i.e EKOGURAD 200 membrane is delivered in 1x10m roll. One layer of 4mm thick approved waterproof membrane shall be torch applied over the primer surface.
Membrane overlaps shall be 100mm for side and 150mm for ends. Tolerance is 10%. Whatever is the quality of the first overlap torching, the seaming of the edges of the membrane shall be done in 2nd operation to allow for checking and re-torching of potential gaps. All membranes overlaps shall be fully torched. Membrane corners and angles shall be fully torched. Any void or air gaps must be corrected if found.
For Skirting, a 4mm thick APP elastomeric bitumen membrane (1 layer) with self protection granule finish, 30 cm wide shall be terminated in to waterproofing termination groove and sealed with bituminous sealant.
Water leak test:

After the membrane is laid, all roof openings shall be temporarily plugged to prevent leak from the opening during the water leak test. It shall be then offered for inspection by submitting an inspection request. Leak test shall be carried out for 48 hrs by filling the roof with water for a height of 50 mm. At the completion of successful water leak test, drain plugs shall be removed and subsequent activity can be started.
Installation of insulation boards :

Upon successful completion of water leak test, 50mm thick approved thermal insulation boards i.e ESCOFOAM shall be placed over the membrane. The fixing of the insulation boards is done by fixing the male butt joints in to the female. It has to be made sure that all the joints are properly aligned and in place.
Installation of Geotextile Separation layer:

After the insulation boards are laid, one layer of approved geotextile fabric i.e A281 shall be laid on top of the polystyrene boards. The overlap shall be 50mm.
Installation of Aluminium Flashing & Mastic Sealant:

The aluminium flashing of 1.5 mm thickness and approximately 150 – 200mm width shall be fixed mechanically by stainless steel screws. The distance between the screws shall not be more than 70 cm. The overlap shall be 2cm. After the fixing of aluminium flashing, polysulphide sealant i.e POLYSEAL PS from M/S Polybit Industries shall be applied inside the top bend of aluminium flashing.
   





B) Method Statement for Basement waterproofing works:

Scope Of Work:

      This method statement covers the roof water proofing system intended to be used for the above mentioned case study project.
2.Approved Applicator:

M/s Water Seal Co.LLC.Abudhabi
3.Materials Used :
<![if !supportLists]>v <![endif]>Masterseal 420:Bitumen Emulsion primer from M/S BASF
<![if !supportLists]>v <![endif]>DAREX AE4: Foaming agent for foam concrete from M/S Grace
<![if !supportLists]>v <![endif]>4mm thick EKOGUARD: APP Modified bitumen membrane from M/S IMI
<![if !supportLists]>v <![endif]>ESSCOFOAM 35-6,50mm thick insulation board from M/S ESSCOFOAM
<![if !supportLists]>v <![endif]>BITUBOARD: Bituminous membrane from M/S Bitustick industries.
SURFACE PREPARATION:

The surface shall be properly prepared by brushing, clearing and leaving the surface free from dust, dirt, grease, loose or projecting particles of mortar etc. The installation of all the pipes, cables and fixing of rain water outlets shall be done prior to waterproofing. All the corners and penetrations shall have cement sand angle fillets.
APPLICATION OF COLD APPLIED COATING:

<![if !supportLists]>v <![endif]>After surface is thoroughly cleaned, first coat of approved masterseal 420, and shall be applied at a rate of one litre/sq.m.
<![if !supportLists]>v <![endif]>Next day, 2nd coat shall be applied at a rate of one litre/sq.m.But in the opposite direction i.e 2nd coat is applied at right angle to first coat.
<![if !supportLists]>v <![endif]>The coating shall be allowed to dry for minimum of 2 days.
FOAM CONCRETING/SCREED CONCRETING:

After the application of masterseal 420 and drying, minimum 50mm thick foam concrete shall be laid as per the mix design already submitted. The initial setting time of foam concrete under present weather is 18 to 24 hrs. Curing for 3 days is required.
APPLICATION OF PRIMER:

After curing of foam concrete is completed, all the areas where the membrane has to be laid shall receive 2 coats of approved IMI primer applied by brush or roller at the rate of 250gm/sq.m. Primer shall be allowed to dry fully before membrane application.
Drying of primer : 12-24 hrs, depending up on weather conditions
APPLICATION OF WATERPROOFING MEMBRANE:

Approved waterproofing membrane i.e EKOGURAD 200 membrane is delivered in 1x10m roll. One layer of 4mm thick approved waterproof membrane shall be torch applied over the primer surface.
Membrane overlaps shall be 100mm for side and 150mm for ends. Tolerance is 10% . whatever is the quality of the first overlap torching, the seaming of the edges of the membrane shall be done in 2nd operation to allow for checking and re-torching of potential gaps. All membranes overlaps shall be fully torched. Membrane corners and angles shall be fully torched. Any void or air gaps must be corrected if found.
For Skirting, a 4mm thick APP elastomeric bitumen membrane (1 layer) with self protection granule finish, 30 cm wide shall be terminated in to waterproofing termination groove and sealed with bituminous sealant.




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