method statement for waterproofing

The method statement for waterproofing is the work procedures and means of controlling specific health and safety risks involved in installing the waterproofing system composed of keyed pre-formed sheet waterproofing applied below the base slabs and sides of the base slab for concrete structures like tunnels, car parks and other structures followed by the application of liquid polymer spray waterproofing membrane.

What is waterproofing?

Waterproofing is the process of forming an impervious barrier to control all water from penetrating a material, including soil moisture, water vapor, and liquid water that is under hydrostatic pressure or specified conditions.

Three Different Method Statements of Waterproofing are presented here:

Method Statement for Waterproofing System [Template](Keyed preformed sheet waterproofing system and liquid polymer spray waterproofing membrane)

Method Statement for Waterproofing of Roof Using EPDM Membranes

Method Statement for Waterproofing Using Cementitious Membranes – Wet Areas such as Bathrooms, Lift Pits, Terraces, Pantry, etc.

Method Statement for Waterproofing System [Template]
(Keyed preformed sheet waterproofing system and liquid polymer spray waterproofing membrane)

I. Description of Works

  1. Objectives

The objective of this method statement is to describe the sequence of operations and means of controlling specific health and safety risks involved in the waterproofing system including a keyed pre-formed sheet waterproofing system to below the base slabs and up both sides of the base slab of concrete structures like tunnels, car parks,  and buildings followed by application of liquid polymer spray waterproofing membrane to structural concrete work other than base slab structures.

The waterproofing work is basically divided into two phases:

a. Phase – 1: Installation of PVC T-Lock (Keyed Preformed Membrane–KPM)
b. Phase – 2: Application of Liquid Polymer Spray Waterproofing Membrane

2. Definitions

SE Site Engineer
QC Quality Control Engineer
SF Site Foreman
PM Project Manager
SA Site Agent representative from the Lab
HSE Manager Health, Safety & Environmental Manager
HSE Officer Health, Safety & Environmental Officer
GIS Geographical Information System
PS Project Specifications
CEMP Construction Environmental Management Plan
QCP Quality Control Plan
HSE Plan Health, Safety, and Environment Plan
GWL Ground Water Level (meter)
NGL Natural Ground Level (meter)
Note: All dimensions are in mm unless specified.

3. Reference

Project Specifications–Protective Treatment for Concrete
Health and Safety Plan
CEMP
General Lifting Plan
Baseline Schedule- Detailed
Material Submittal for Waterproofing System
Method Statement for Concrete Works
Waterproofing Shop Drawings
This Method Statement shall be read in conjunction with the following Standards, Plans, and Documents;
Project Drawings
Logistics Plan
Health & Safety Plan
Other Relevant Procedures
Manufacturer’s Instructions

4. Responsibilities

Project Manager

Supervise closely, the activities designated to them and ensure that all instructions and safety procedures are followed and strictly adhered to.

Supervise the work to ensure that technical, quality, safety, and purchase order requirements are met; Attend daily site meetings and communicate his daily report with the Project/Site Engineer; Participate in training and development of his subordinates; Organize with the Project/Site Engineer to ensure the availability of plant, equipment, and labor to his designated work activities; Closely monitor the usage of consumable and materials by his crew in order to minimize wastage; Assess craftsmanship of subordinates under his control.

Construction Manager

Carry out a pre-construction survey to fix the locations and corresponding elevations as per the approved shop drawings.

Ensure quality and compliance during phases of surveying works and the regular checking of the surveying equipment or periodic calibration from third parties.

Ensure the validity and the serial number of calibration certificates are available and posted on the survey equipment.

Ensure proper safety guarding of surveying equipment.

To maintain the records of all surveying equipment handled.

Site Engineer

Supervise operations in accordance with the approved method statement for waterproofing, shop drawings, specifications, material submittals, and schedules to achieve the acceptance of the project deliverables.

Site Supervisor

Supervise closely, the activities designated to them and ensure that all instructions and safety procedures are followed and strictly adhered to.

Supervise the work to ensure that technical, quality, safety, and purchase order requirements are met; Attend daily site meetings and communicate his daily report with the Project/Site Engineer; Participate in training and development of his subordinates; Organize with the

Project/Site Engineer to ensure the availability of plant, equipment, and labor to his designated work activities; Closely monitor the usage of consumables and materials by his crew in order to minimize wastage; Assess craftsmanship of subordinates under his control.

Chief Surveyor /Land Surveyor

Carry out a pre-construction survey to fix the locations and corresponding elevations as per the approved shop drawings.

Ensure quality and compliance during phases of surveying works and the regular checking of the surveying equipment or periodic calibration from third parties.

Ensure the validity and the serial number of calibration certificates are available and posted on the survey equipment.

Ensure proper safety guarding of surveying equipment.

To maintain the records of all surveying equipment handled.

Survey Aide

Maintain and use Surveying equipment. Assist Surveyors in taking measurements, record measurements manually or electronically, and peg out boundaries.

HSE Manager

Health, safety, and environmental (HSE) managers generally plan, coordinate and implement issues and directives within the organization.

They ensure safe environmental working conditions for all employees.

HSE Engineer

Ensure enforcement of safety procedures in accordance with the approved HSE Plan.

Will be closely monitoring the site engineer’s strict implementation of the MS and Risk Assessment, the use of proper tools and equipment to maintain safety, certifications of equipment and their adherence to safety regulations, reporting of any unsafe work or stopping work that does not comply with ES&H procedures.

Environmental Officer

Report to HSE Manager. Ensure enforcement of environmental procedures in accordance with the approved HSE Plan. Will closely monitor implementation of MS and Risk Assessment, the proper storage and handling of materials. Report any breaches of regulations and stop work if required to get compliance with ES and H procedures.

Lifting Competent Person

The role of the Lifting Competent Person is to ensure compliance with safe practices for the loading and unloading of equipment and materials on site.

First Aider

The first aider responds promptly when requested, operates with competence, knows how to secure additional help when needed, reports incidents and actions taken, and complies with requirements for certification.

Banksman

The role of a bank-man is to provide additional eyes and ears to assist the operator of the equipment to navigate or operate safely.

5. Interfacing with Other Operations

For Phase – 1: Surface preparation of RC Base Slab and installation of reinforcement

For Phase – 2: Completion of Reinforced Concrete Works with required embedment

6. Duration, Phasing with the Subcontractors

Refer to the approved baseline schedule for the duration of waterproofing works. Ref.: xxxx

7. List of Subcontractors

Subcontractor

 As per approved Subcontractor

II. Resources

1. Plant and Equipment

DescriptionNo. of UnitsApplication
Leister Varimat Welding Machine3Hot Air Welding of T-Lock
Leister Triac S Welding Machine10Hot Air Welding of T-Lock
Air Compressor2Spray Membrane
Weather Station Instrument1Testing Environment
Hydracat Dual – Component Airless Spray2Spray Membrane

2. WorkForce

DesignationNo. of Persons
Site Engineer1
Site Supervisor2
Waterproofing Technicians8
Waterproofing Assistants16
QA/QC Engineer1
HSE Engineer1
First Aider2

3. Light Tools

DescriptionNo. of UnitsApplication
Pressure Rollers10Application of Jointing
Holiday Test Machine1Testing Membrane
Positester Defelsko Machine1Testing Membrane
Small Hand ToolsAs per site requirementCutting, Testing
Elcometer 106 tester1Check the concrete surface

III. Materials

(These are only examples of material brands)
Euroseal PVC T-Lock (Keyed Preformed Membrane– KPM)
Internal and External Waterstop – Type 3
Injection Hose
Swelling Bar
Integritank Spray Membrane- Liquid Polymer Spray Waterproofing (Part A & B)
PA1 Primer
Metaset Structural Adhesive
Debonding Tapes and Reinforcement Scrim
PVC Flat Strip (2.0mm)
PVC Dilation Tape (2.0mm)

Note:
Test Certificates – Applicable. Please refer to the submitted Material Submittal for Waterproofing System.

IV. Site Planning

Refer to approved Baseline Schedule- Detailed, ref. no.: xxxxx for the initially planned duration of work. However, the duration can be indeterminate but not critically affect the program of work.

1. Preparation

a. Permits from the concerned authority shall be obtained prior to starting work at the site.

b. The contractor shall ensure that all gate passes, permits, tools, materials for safety precautions, manpower, and equipment are available before the commencement of work.

c. The Site Team shall make sure that access roads are always clear from any obstruction and site is always accessible.

d. Organization Chart is attached in Appendix – L.

2. Site Clearance

Before commencing the work, the area shall be cleared of all debris, materials, or other obstructions.

3. Traffic Management

a. The Site Team with the assistance of the Safety Officers shall coordinate logistics and materials movement through the site following the direction and road signs displayed on site. The required diversion routes shall be marked on drawings including the required traffic signs.

b. The Work Permits and Operator Certificates shall be compiled and filed for reference by authorized personnel.

4. Pre-construction Safety Meetings

The meeting shall be scheduled prior to the beginning of the work and before any Subcontractor starts on the project.

a. General contractual safety, health, and environmental requirements.

b. Depending upon the phase of waterproofing works, safety concerning to electrical, working at height, working with chemicals, etc. shall be discussed to emphasize these meetings.

c. Roles of the contractor, subcontractors, authorized representatives, and all project workers.

d. Accident reporting requirements.

e. Specific details of the work to be performed along with the use of personal protective equipment.

f. Emergency procedure.

V. Procedure-Method statement for waterproofing system

Waterproofing System is divided into two phases which are the application of PVC T-Lock:

Membrane and application of Integritank spray membrane. The T-Lock Keyed Pre-formed Membrane  (KPM) membrane is applied before the concrete work start and the Spray membrane is applied after the concrete has attained the required criteria for the application. The contractor shall execute the trial test section on the vertical and horizontal surface which shall include details of construction and expansion joint, complete with protection system and approval before application to the structure.

The subcontractor team at the site shall be responsible to check all items of waterproofing system against the sequence of construction starting from the laying of reinforcement bars for the base slab till the finishing of backfilling, considering the following:

a. Subcontractor to arrange for 24/7 supervision of responsible representative at the site for Backfilling surveillance, installation of protection board, and waterproofing repairs as required.

b. The subcontractor is to provide the Specific Organization Chart of the Supervision Team for the project.

c. The subcontractor is to sign a separate checklist as attached in Appendix F to check the waterproofing membrane during the backfilling work application.

V.1 Phase – 1: Application of Keyed Pre-formed Membrane (PVC T-Lock)

V.1.1 Installation of Keyed Pre-formed Membrane (KPM) to Base Slab

1. Blinding concrete to be smooth and even finished with no sharp projections or abrupt steps, clean and free of loose stones or debris.

2. Blinding concrete surface condition and area for laying membrane to be agreed upon with Main Contractor, Consultant, and subcontractor site in charge.

3. Unroll the KPM across the floor so that the keys are aligned transversely to the longest dimension of the structure.

4. Where the KPM will be continued up the wall, cut the strip to the appropriate length to provide an upturn to the edge forms. The upturn must be of sufficient length (500mm vertical minimum and for practical reasons can be extended up to 1000mm) to allow connection to the external waterproofing. Refer to Typical Drawing ref. no. xxx. Fix the top of the membrane to formwork by staples. Apply sealant to the top of the membrane to avoid grout running behind the membrane. (Refer to photos below).

T-lock membrane waterproofing
PVC T-lock membranes used in the method statement for waterproofing

5. Where the lengths of the membrane (i.e. parallel to the keys) have to be joined longitudinally, overlap the edges of the sheets, and use an automatic welding machine, hot air gun, and pressure roller to provide a welded joint. The welded single seam will be a minimum of 30 mm wide minimum. Where sheets of membrane need to be joined end on end then cut back the keys of both sheets from the end of each sheet for 80 mm width, overlap sheets, and weld sheets together. Reweld keys back into position. Refer to Typical Drawing ref. no. xxxxxxx. Apply Integritank Liquid Membrane and Metaset Adhesive to the keys of the joint as added protection. (Refer to photos below):

joint welding of waterproofing membrane ends
Welding of waterproofing membrane joints

6. At the intersection between the base and the side form, install a 25 mm x 25 mm prefabricated angle fillet to allow T-Lock Membrane to be upturned against the form face so that keys do not need to be cut. Refer to Typical Drawing.

7. Refer to the approved Shop Drawing for T-Lock folding and terminations to structural concrete ref. no. xxxxx. However, PVC T-Lock upturn should be discussed at the site prior to fixing as per drawing notes. Additional layer thickness is to be added at turns bends and edges as reinforcement, especially underneath portions.

8. Heating temperature and method of welding to be in accordance with the T-Lock manufacturer’s training and ambient temperatures.

9. Where the external waterstop is to be installed at expansion joints, cut off the T’s (using a sharp blade) and weld the waterstop with a hot air gun and pressure roller at both sides of waterstop minimum of 20 mm, leaving the center part not welded. Refer to Typical Drawing ref. no. xxxxx

10. Internal waterstop will be installed at a specified height as shown on the approved reinforcement detailed drawing using best management practice.

V.1.2 Inspection and Testing (KPM)

1. A site trial (mock-up) will be carried out to demonstrate the welding and inspection procedures.

2. For single-seam welds, visually inspect the seam for discontinuity and run the screwdriver blade along the seam to check for discontinuity. Visually check that melted PVC has bled out evenly along the welded joint.

3. Spark test all the seams with a holiday/pinhole detector with the direct current voltage set for a 4mm thick membrane (two layers) and not exceeding the material’s dielectric strength. (Note all the overlapped seam welds be tested 100%). (Refer to the photo below).

spark testing of waterproofing application
Spark testing also applicable to T-lock waterproofing membranes installation

4. Welding of external water stop to T-Membrane will not be tested as it is used to keep the water stop in place only.

5. If the voltage is set to 10,000 V, ensure that only overlapped seam welds are brushed with the sensor. The membrane thickness will be 4mm because of the overlap. This voltage shall not be used on the 2mm thick membrane because of the danger of burning pinholes.

6. Safety precautions (trained operatives, exclusion zone, and equipment safety cables inspection) are to be observed when using high-voltage testing equipment. The spark tester is not to be used in wet conditions, where reinforcing steel is fixed, or where danger from explosion exists.

7. The membrane shall be inspected for damage as a hold point after the bottom layer of reinforcement has been completed.

V.1.3 Remedial Work to KPM

1. Prior to concreting, any extensively damaged KPM will be cut out to the nearest adjacent welded seams and a new strip of membrane fitted, joined by single seam welding with 30 mm weld. The repair area will be tested by running a flat-headed screwdriver along the welded joints to see any missed welds.

Note: The subcontractor will monitor the rebar installation on the base slab and will repair any damage as it occurs or is first noted.

2. Small splits, tear punctures, or tie bolt holes may be sealed by hot welding a patch of KPM with an overlap of at least 30 mm. (Refer to the photo below).

3. Punctures caused by nailing or such must be sealed by hot welding a patch 50 mm diameter or 50 mm square over the puncture hole.

4. Repairs to the T-Lock membrane cannot be inspected by high voltage spark testing when the reinforcement has been placed as there is a safety concern for the operator. In such cases, physical checking with a flat-headed screwdriver shall only be carried out.

V.1.4 Concrete Spacer Blocks

1. Concrete spacer blocks should fit between the keys of the T-Lock and should have dimensions 100 mm x 50 mm.

2. Spacer blocks to be staggered.

3. The maximum spacing of spacer blocks shall be as referred to in approved shop drawings.

V.2 Phase – 2: Application of Integritank Spray Membrane

V.2.1 Preparation of Concrete Substrate

1. All concrete decks shall, where necessary, be prepared by suitable mechanical means such as diamond grinding, vacuum blasting, or grit blasting to provide a sound surface free from laitance.

2. Concrete surface to receive Integritank should be a minimum of 14 days old or should achieve a 0.7 MPa pull-off value as described below. All defects on the surface of concrete and dry cracks should be repaired to the satisfaction of the approved applicator of the waterproofing. Refer to Application Guidelines of Integritank, attached.

3. Horizontal surfaces to be U4 finish, the vertical surface will be formed finish. Ensure that there are no sharp projections or tie wires, and clip off any nails. Blowholes are to be filled with an epoxy mortar approved by the approved applicator of the waterproofing.

4. Before the Integritank is applied, the surface condition of the concrete will be checked to ensure that the adhesive bond will be achieved. The adhesion of the membrane to the concrete surface will be checked by the use of Positest Defelsko. Place a 50 mm diameter dolly every 50 m² coated in fresh Integritank onto the concrete surface to be tested. Allow the Integritank to cure for at least 4 hours and then pull the dolly off the concrete using the Positest Pull-off tester and note the pull-off value measured.

5. If tensile adhesion tests as described above fail to achieve 0.7 MPa and the failure mode is in laitance then surface laitance may be removed by light shot blasting or grinding. If the failure is less than 0.7 MPa and the failure mode is in the concrete substrate then accept the value of pull-off as the concrete surface strength.

Note: If the tensile adhesion test is less than the required value, the main contractor must prepare the surface to achieve the value by light sandblasting or grinding.

6. Following preparation work, perform a joint inspection (INR) with the Engineer/Main Contractor/Waterproofing Subcontractor to ensure the surface is fit to proceed with membrane application.

7. The concrete surface is to be checked to be touch dry before the application begins. Check that substrate temperature is at least 3 °C above dew point temperature. Check the dew point temperature before the commencement of the spray membrane and at the start of every work shift.

8. In case of doubt, check the surface with dry tissue paper. If there is no moisture pick-up, the surface moisture condition is suitable. Before the application of primer, blow down the concrete substrate with compressed air to remove dirt and dust. Concrete surface moisture checking shall be done at the site before the application of the spray membrane.

9. The spray team shall not apply the membrane if the wind speed is too high which shall cause overspray and/or loss of material. The spray team shall also not apply the membrane if the wind has airborne dust and dirt that will contaminate the spray membrane. Confirming the proper training of the spray team, measuring, and understanding wind speed or dust contamination in the air is not necessary. Trained spray teams are experienced enough to stop and resume work depending on weather conditions.

10. The subcontractor and main contractor shall carry out the surface moisture content test through a third-party lab. It shall be done only once but before starting actual work. This can be carried out on mockup also.

V.2.2 Application of Integritank

1. Integritank will be applied as a 2.0 mm minimum thick coating in two coats.

2. Wet film thickness checks of the sprayed membrane measured prior to the Integritank setting are to be taken every 2 m² manually by the sprayer using a wet film gauge. The target thickness is 1.2 mm on each coat. The target overall consumption rate per coating is 1.4 kg/m². All records for consumption will be recorded in QA/QC forms. Spray supervisor to check the wind and airborne conditions on site before commencement of work to either protect the work substrate or abandon the work until more favorable conditions are available.

3. Mask any furniture or surfaces not to be coated to protect from overspray. Prepare boundaries with a straight edge formed with masking tape and remove the masking tape before the membrane starts to gel. The surface of the prepared concrete will be primed using spray or roller-applied PA1 primer at a rate of approximately 0.2 ± 0.05 kg/ m². Allow the primer to cure until tack free, normally approx. 30 minutes

4. Depending on temperature add 6kg-8kg of hardener powder (Di-benzyl peroxide) into the 192 kg drum of Integritank Part B either yellow or grey and mix thoroughly with the air-driven mixer. Once the catalyst has been added Part B becomes active. To avoid any problems it should ideally be used the same day. The typical Pot Life of a 24 kg bucket of Integritank Part B containing the catalyst in the temperature range of 10°C-40°C is as follows:

Temperature (°C)Pot Life (Standard catalyst
addition)
4016 hours
3050 hours
2316 days
12 (Average Temperature)Not cured after 80 days

5. Mix Part A thoroughly before use with the air-driven mixer.

6. Attach Integritank Part A and Part B to Hydracat pump for spraying in equal proportions.

7. The equipment is a plural component pump, metering Part – A & Part – B on a 1 to 1 ratio by volume mixing in line and delivering the mixture by airless spray.

8. The applicator shall be skilled and experienced and shall be able to spray the coating according to good practice. The applicator will ensure that the coating will be applied in a uniform manner, with overlap (approx. 150 mm) at the edges of the spray pattern. The applicator should monitor the process and his technique through regular visual checks and wet film thickness checks of the freshly applied coating.

9. Spray apply Integritank yellow coat at the rate of approximately 1.4 kg/m² to achieve a target wet film thickness of 1.2 mm (equal to the dry film thickness of more than 1.0 mm). Allow curing for a minimum of 30 minutes.

10. Inspect the yellow coat for visible holidays and misses and snag as necessary with hand-mixed Integritank yellow coat.

11. Same procedure will be applied to the 2nd coat which is grey in color.

12. Note: Part B material is pigmented either yellow or grey as a visual aid to achieving full coverage. There are no detrimental effects of applying grey on grey or yellow on yellow providing the 2mm thickness is achieved.

V.2.3 Application of Integritank at Day Joints
1. Spray Integritank to a convenient termination to a straight edge formed with masking tape to each component (Primer & yellow coat to be stepped back 50 mm) to allow overcoating of each layer. Remove the tape immediately after spraying the coating to avoid any fretting. When overcoating, bring the fresh Integritank over the existing to form a 50 mm overlap to each layer.

V.2.4 Treatment of Construction Joint (Refer to V.3.3.1 & V.3.4.1)

1. For construction joints where there is no external Waterstop, apply a stripe coat of 0.5mm thickness of Integritank membrane over the debonding tape over a width of 180mm (90 mm on either side of the construction joint). Bed in the reinforcement scrim (175 mm width) while the stripe coat is still liquid. Once the scrim is embedded the normal 2 coats Integritank 2 mm membrane can be applied over the whole surface.

2. Add 2mm PVC Flat Strip (200 mm wide) membrane over the Integritank and fixed to the spray membrane by Metaset adhesive. Apply further Metaset adhesive to the top face of the PVC Strip and apply 2mm Integritank membrane leaving center part of PVC Strip not sprayed.

V.2.5 Application of Integritank to Interface area of T-Lock Membrane

1. Repair all fish lips and broken edges with epoxy. Remove all nails grind off shape edges and use light brush grinding or sandpaper on the surface of T-lock where Integritank will overlap. Clean the surface of the T-lock membrane longitudinally (200mm wide) Apply Metaset Structural adhesive by using the brush at approx. 1Kg /m² coverage. Wait until adhesive becomes tack free then apply Integritank system. Bond testing may be done in this location if instructed.

V.2.6 Application of Integritank of Expansion Joint on Wall and Roof

1. (Refer to V.3.1, V.3.2 & V.3.3)

V.2.6.1 For Walls

1. Repair both sides of the waterstop for any fish lips and broken edges with epoxy. Remove all nails and grind off sharp corners.

2. Fix 50 mm wide masking tape vertically on to the center of external waterstop.

3. Apply Metaset Structural adhesive by brush. Wait until adhesive becomes tack free then spray Integritank system on top of external waterstop.

4. Remove the masking tape. Once the liquid is dry apply Metaset Structural adhesive on both edges of waterstop where Integritank is sprayed earlier and carefully fix the PVC sheet membrane.

5. Spray Integritank on both sides of PVC sheet membrane leaving center part not

sprayed. (Refer to Detailed Shop Drawing ref. no: xxxx. Bond testing may be done in this location if instructed.

V.2.6.2 For Roof

1. Adhere 2 mm PVC dilation tape to concrete to cover the expansion joint except over the de-bonding tape on the concrete.

2. Apply Metaset Adhesive to the top of dilation tape and place a 2 mm PVC flat strip over the joint. Apply a de-bonding tape over the center section of the PVC Flat Strip.

3. Apply Metaset adhesive over the PVC flat strip and apply the 2 mm Integritank membrane. Remove the de-bonding tape.

V.2.7 Repair and Replacement of Integritank

If any damage or defect occurs, such as blisters, misses, or large pinholes, it will be repaired as follows:

1. Grind or sand the edges of the broken membrane and clean the surrounding area with MEK solvent or acetone solvent.

2. Using a small scraper, hand mix equal proportions of catalyzed Integritank Part B with Integritank Part A until completely blended.

3. Apply the new membrane with a spreader or scraper to replace the removed membrane and extend the application to a 20-30 mm overlap in each direction. A 2.0 mm layer may be applied in one operation.

4. For larger areas of damage or a complete replacement, it is necessary to remove the Integritank from the substrate. Mark out the repair area into a square or rectangular shape. Cut through the membrane along the perimeter of the repair area to establish a neat edge. Due to the tenacious bond of the membrane to the concrete substrate, this membrane removal can only be done by mechanical means – grinding and shot blasting.

5. If some residual Integritank inside the repair area cannot be easily removed from the substrate it is acceptable to allow it to remain, providing it is fully bonded.

6. Prime surface with PA-1 primer and spray Integritank in two coats, as described in this method statement.

7. Pinholes and blowholes shall be filled with SIKADUR 31 SLOW or CONCRESSIVE 2200 BASF (or equivalent). Cracks and surface undulations or surface-level mismatches of the concrete surface shall be filled/leveled with approved epoxy mortar.

V.2.8 Quality Assurance

1. The maximum substrate temperature for Integritank spray membrane is 50ºC. However, work shall be limited to being done at ambient temperatures of 40ºC for workers’ comfort. In summer months work shall be done after sundown. The Elcometer Weather Station Machine available on site calculates dew point temperature. This machine records ambient temperature, substrate temperature, and relative humidity to get a dew point temperature.

2. Measure the deck surface temperature. Record the measurements on the proforma. The Integritank Membrane shall be applied at substrate temperatures at least 3ºC above Dew Point temperature to avoid surface moisture. The internal concrete moisture level is of no importance for Integritank. It is only the surface dryness that dictates the proceeding of the Integritank spray work. The concrete surface should be touch dry tested by hand or with a paper tissue to check for dryness. The equipment to measure the dew point shall be calibrated.

3. Record the batch numbers of all materials used. Record the weight of Integritank consumed for weight/thickness reconciliation. This information is to be recorded on the daily inspection proforma.

4. Coating application by airless spray is a special process that relies on the skill and experience of the applicator. The applicator will monitor the performance and thickness of the sprayed coat by regular dipping with a wet film thickness gauge.

5. The following application and snagging, check for pinholes and holidays using a high voltage discontinuity tester. The area will be checked with a high-voltage spark detector, with the voltage set between 8,000 – 10,000 volts.

6. Adhesive Bond Test and Dry Film Thickness (DFT) Test of Integritank spray membrane shall be carried out for the final layer. The test frequency for the simultaneous bond test and DFT test shall be at every 100 m² or as directed by the engineer.

7. Wet film thickness checks on each coat of Integritank shall be carried out at a frequency of 1 per 2 m². The coating shall be done by the sprayer so if an area is less than 1 mm thick the same can be sprayed more and shall be rechecked.

8. The dry film testing is done on the finished membrane by a destructive cutout and direct measurement with calipers. This dry film thickness testing is usually done at the same location as the membrane post-application Pull off testing to limit the destruction of the finished membrane. The relationship between NDT and DT for checking the thickness of the film shall be established on-site during mock-up. Depending on the result and its agreement with all parties, further tests shall be conducted for checking spray thickness.

9. All required quality control tests for each application of the system are to be carried out according to the approved schedule plan, considering that the third-party check test should be carried out randomly as directed by the Engineer on monthly basis.

V.2.9 Waterproofing of Penetrations

1. For steel dowel bars at approach slabs on corbels near tunnel roof level if applicable clean and coat the bottom 10mm of the bars using Stirling Lloyd ZedS94 primer before applying Integritank membrane over the corbel.

2. For pipe penetrations clean and coat of the pipes using Stirling Lloyd primer before applying Integritank membrane around the pipe penetration. Refer to shop drawings for the type of primer.

3. Earthing and pipe penetrations shall be considered as special items of checking and waterproofing arrangement around them shall be checked and signed by the subcontractor for each step which is further to be inspected by the consultant. Necessary site adjustments shall be made on-site for the same purpose other than approved drawings.

V.3 Phase – 3: Waterproofing of Joints

V.3.1 Installation of Waterstops in Expansion Joint

1. For Base Slab: Remove keys of PVC T-Lock Membrane approximately 200mm on either side of the expansion joint centerline. Place the external waterstop on the PVC T-lock membrane and hot weld the edges of water stop (20 mm wide) continuously. Place internal waterstop in the correct location. Tie back edges of waterstop to reinforce using plastic ties or tie wire to keep waterstop flat and straight.

2. For Walls: Place the external waterstop against formwork and staple the edges of waterstop to keep the waterstop in place. Place the internal waterstop in the correct location. Tie back edges of waterstop to reinforce using plastic ties or tie wire to keep waterstop flat and straight.

3. For Roofs: Place dilation tape centrally over expansion joint and adhere concrete using Metaset structural adhesive as shown in drawings. Place the internal waterstop in the correct location. Tie back edges of waterstop to reinforce using plastic ties or tie wire to keep waterstop flat and straight.

4. The tie-in at the project limit will be specially studied, detailed, adjusted, and done on-site with each step confirming as per approved mock-up.

V.3.2 Installation of Protection to Waterstops

1. For Walls: Place PVC protection strip over external waterstop and adhere edges using Metaset structural adhesive in accordance with the drawings.

2. For Roofs: Place PVC protection strip over dilation tape and adhere edges using Metaset Structural Adhesive in accordance with drawings.

V.3.3 Installation of Injection Hoses

1. For Construction Joints: Place the injection hose directly onto the concrete substrate in the location as shown in the drawings. Drill and fix hose clamps at 250 mm center approximately to firmly hold the injection to the concrete. Connect a clear hose at the termination of the injection hose with a hose connector and fit the injection point. Place injection point to reinforcement and formworks at locations as directed by the drawings.

2. For Expansions Joints: Place one injection hose on each edge of the internal waterstop. Fix hoses to water stop with plastic ties. Connect a clear hose at the termination of the injection hose with a hose connector and fit the injection point. Place injection to reinforcement and formwork at locations as directed by the drawings as directed on the drawings.

3. X1 hoses are typical to be installed in walls for Construction Joints and Expansion Joints where distances between injection points are below 20m. X100 hoses are typical to be installed in the base slab and roof for construction joint and expansion joint where distances between injection points are 40 m in length.

4. Test Report for the X100 injection hose is attached in Appendix P. The same shall be confirmed by a mock-up test.

5. The location of injection hose points should be in one alignment with constant distance for the base slab (500 mm above final floor finish), wall, and roof slab.

V.3.4 Installation of Swelling Bar

1. Place Superswell 47B in the center of the construction joint as shown on the drawings and fix the concrete substrate using contact adhesive to keep the swelling bar firmly in contact with the substrate.

V.4 Backfilling, Protection against backfilling and repairs

1. Protection board to be installed against vertical waterproofing membrane as required prior to backfilling. Careful layer-by-layer monitoring of the backfilling operation will be carried out and approved by the subcontractor to be aware of any damage caused to the membrane by the compaction equipment. Any damage shall be repaired immediately.

2. The wall will have a protection board and backfilling to be witnessed and monitored by the subcontractor and main contractor for damage to the waterproofing. If the damage is observed then the backfilling operation is to be halted until repairs are completed and inspected.

3. For the roof slab, a protective concrete screed of 75 mm thickness shall be installed directly on the Integritank if a protection screed is demanded.

4. During backfilling work the work will be witnessed and reinforced for any damage caused to the waterproofing from the backfilling operation. Repairs to the damaged membrane will be immediately undertaken in accordance with the method statement for the waterproofing system.

5. For performing backfilling, its layer thickness, operation sequence, and testing criteria, reference shall be made to approve revision of method statement for respective backfilling activity.

6. Backfilling material around of structure shall only be hand placed.
Compaction of backfilling within 1.5 m of the structure shall only be achieved by manually operated tools & equipment. Towed or self-propelled vibrating rollers or heavy compaction equipment shall not be used within 1.5 m of any structure.

7. Backfilling shall be done with approved backfilling material. Up to 1.5 m from the structure, backfilling shall be done with stone/rock particles having a size, not more than 0 – 50 mm with a manually operated compactor. For areas, more than 1.5m away from the structure, backfilling shall be carried out with stone/rock particles not more than 75 mm.

8. For structural backfill, the material shall be placed in a layer within the effective range of compaction of the plant provided that the maximum loose (uncompacted) thickness of each layer shall not exceed 200 mm to 300 mm. The compacted thickness shall be about 150 mm.

9. Each layer of fill shall be checked and assessed by a waterproofing subcontractor and a separate checklist will be signed to ensure no damage on the waterproof sprayed membrane prior to proceeding to the next layer.

VI. Risk Assessment

Please refer to the attached document in Appendix D.

VII. Permit and Licensing Requirements

All necessary permits shall be obtained.

VIII. Diagrams, Maps, and Survey Data

Please refer to Typical Drawing ref. no.: xxxx.

IX.Pre-Start Safety Briefing Arrangements

Refer to Risk Assessment in Appendix D.

1. Protective and Safety Equipment

All workers involved shall be equipped with adequate PPE as stated below:

a. Safety Helmet with Company Logo

b. Safety Boots

c. High Visibility Vest

d. Safety Goggles

e. Hand Gloves

f. Coveralls

2. Information to Personnel

a. Safety Induction

b. Job training

c. Superintendents Notices/Memos

d. Toolbox talks

e. START Card

3. Special Safety Requirements

a. All necessary personal/protective equipment (PPE).

b. Banksman, wearing distinctive vests, shall be assigned to help operators maneuver their equipment.

c. The equipment operators shall possess the required licenses and certificates.

d. Generated dust shall be controlled by periodic water spraying.

e. The required TSTI will be prepared prior to the commencement of work and positively implemented.

f. The project safety officer is responsible along with the project zone site engineer for ensuring that all operations are carried out with due regard to the safety of all project personnel & property.

g. All working activity shall comply with Client Safety Procedure.

h. First aid material.

i. General management of protection/operation hazards is to be observed.

4. Emergency Procedures

The Flow chart below (insert the responsible persons and their respective contact numbers) shows the emergency contact number during work.

X. Supervision and Monitoring Arrangements for Waterproofing Work

Construction Manager

He is in charge of all construction activities. Schedule the project in logical steps and budget the time required to meet deadlines. Inspect and review projects to monitor compliance with building and safety codes and other regulations.

Temporary Works Construction Manager

To support the project delivery teams, to support and lead the management and delivery of temporary works engineering whilst ensuring program, cost, quality, and safety objectives are achieved.

Site Engineer

The Site Engineer shall evaluate the number of materials consumed by each trade to be compared against the planned quantity.

Site Foreman

A construction foreman is responsible for supervising the workers and also doing actual construction work. The foreman monitors employees to ensure that the work is done efficiently and within quality standards.

Chief Surveyor

A Chief Surveyor ensures that surveying data are collected and recorded accurately and that all company procedures are followed by crew members.

QA/QC Engineer

The QA/QC Engineer shall monitor whether the installation works are conforming to the required quality otherwise he shall notify the Site Engineer should he find non-conformance to the ongoing activities. The Site Engineer shall immediately rectify the work to avoid receipt of NCR from the QA/QC Engineer.

HSE Engineer

The Safety Engineer shall be full-time at the site and shall frequently visit all the ongoing works at the site. All safety violations and on-conformance of the HSE Plan shall be registered and immediate action shall be done in coordination with the Site Engineer.

Environmental Manager

Will closely monitor implementation of MS and Risk Assessment, the proper storage and handling of materials.

Lifting Competent Person

The role of the Lifting Competent Person is to ensure compliance with safe practices for the loading and unloading of equipment and materials on site.

XI.Environment and Quality Issues

1. Precautionary Measure

All precautionary measures shall be briefed to all workers prior to commencing activity

2. Disposal Requirements

All waste shall be disposed of as per the Construction and Environmental Management Plan, ref.: xxxxx, and as per Government approved disposal areas.

3. Inspection, Test, and Sampling

Request for Inspection and Testing will be submitted prior to and after the execution of works.

A mock-up sample shall be provided on-site for approval prior to the execution of works where required.

4. Quality Assurance Requirements Table Refer to Project Quality Plan

a. Project Specifications

XII. Attachments

1. Reference Documentation

a. Technical Data Sheet

2. List of Appendices

Appendix A: Site Location

Appendix B: Shop Drawing, ref.: xxxxx

Appendix C: Field Testing and Inspection Plan

Appendix D: Risk Assessment and Job Hazard Analysis

Appendix E: Pictures of Instruments

Appendix F: Formats for Inspection and Checking

Appendix G: Photographs for Installation of Integritank

Appendix H: Copies of References

Appendix I: Method of T Lock Field Testing

Appendix J: Application Guidelines – Integritank

Appendix K: Calibration Certificates

Appendix L: Subcontractor Organization Chart and Contact Numbers

Appendix M: Confirmation from Stirling Lloyd on Moisture and DT

Appendix N: Test Report for X100 Injection Hose (42.0 meters)

Method Statement for Waterproofing of Roof Using EPDM Membranes

Product Delivery, Storage, and Handling

A. Deliver materials etc.: the job site in the manufacturer’s original, unopened containers or wrappings with the manufacturer’s label, brand name, and installation instructions intact and legible. Comply with the manufacturer’s written instructions for proper material storage.

1. Store materials except for membrane, between 15°C and 27° in an air-conditioned space (container) protected from water and direct sunlight.

2. Store materials containing solvents in dry, well-ventilated spaces with proper fire and safety precautions. Keep lids on tight.

B. Material inspection shall be carried out for all permanent materials. Any materials, which are found to be damaged, shall be removed and replaced.

General Work Condition

a. Work Sequence

1. Schedule and execute work in accordance with the site construction program and with site conditions.

2. Do not disrupt activities in occupied spaces.

Temporary Facilities and Controls

A. Temporary Utilities:
1. Water power for construction purposes and lighting should be available at the site and should be made available when required.
2. When available, electrical power should be extended as required from the source.
Provide all trailers connections and fused disconnects.

B. Temporary Sanitary Facilities
Sanitary facilities should be available at the job site.

Materials

Hot applied liquid membrane: Shall be CCW SOC H0i Applied Membrane, rubberized asphalt compound
Reinforcing fabric: Shall be reinforcing fabric which is a 1.35 oz/square yard spun bonded polyester fabric
Primer
EPDM 1.52mm thick waterproofing membrane
Bonding adhesive
Tape 15.24 cm wide
Splicing Cement
Extruded Polystyrene Insulation Board (50mm Thick) (32-36 kg/m³)
Termination bar
Lap Sealant
Water Cut-off mastic
Geotextile separation and protection layer
Paver Mixed (Aggregate)
Gravel 20-40mm

Procedure for Waterproofing of Roof Using EPDM Membranes

Surface Preparation

The surface should be free from defects. Any surface defects are to be repaired as per approved MS – Repair of Concrete, prior to screed works.

Sand-Cement screed (thickness min. 50mm to 150mm max.) laid to fall will be cast on top of roof slabs as per approved drawings.

Install a 50 mm x 50 mm angle fillet on all internal corners.

Application of Hot Rubberized Membrane

Works shall be carried out according to the manufacturer’s application and installation instructions.

To Horizontal Grade:

Heat the membrane blocks in a twin wall kitten with continuous agitation and apply at temperatures between 190.5°C to 201.6°C (Caution: Do not exceed the maximum safe operating temperature of 204.4 °C.

B. Apply heated hot applied membrane at a rate of 1.62 sq. m. per gallon or as required to obtain an average thickness of 2.2 mm over the primed area.

C. Apply the reinforcing fabric and any required flashings while the membrane is still warm and tacky. Cut and trim off any wrinkles or overlapping sections of the reinforcing fabric.

D. Apply a second coat of hot applied membrane as required to obtain a total thickness of 4.5 mm.

E. Flash all penetration to conform with the manufacturer’s recommendations and as shown on approved drawings.

To Vertical Grade:

A. Membrane Installation

Follow manufacturer’s applicable specifications for particular surface preparation procedures, membrane positioning, and adhesive application requirements.

In preparation for membrane splicing, overlap adjoining EPDM membrane sheets approximately 15.2 cm.

B. Membrane Splicing With Tape

Tape splices must be a minimum of 13.9 cm wide using 15.2 cm wide tape extending 0.3 cm minimum to 1 .2 cm maximum beyond the splice edge.

Prior to tape and flashing application, the splice area must be primed.

C. Membrane Termination

The upper ends of the EPDM membrane should be held tight using a termination bar, water cut-off mastic, and sealed with an approved sealant.

D. Flash all penetration to conform with the manufacturer’s recommendation and as shown in the approved shop drawing.

On completion of the application of waterproofing material to an existing concrete roof but before the application of insulation and protection, seal off all rainwater outlets and flood the roof to a depth of 25mm. The Contractor shall make up any loss of water due to evaporation or leaks. After 48 hours, a visual inspection of the roof shall be undertaken from inside the building in the presence of the

Consultant to establish if there are any leaks in the structure. The Contractor shall locate and seal any leaks.

Carry out inspections in accordance with the ITP (Inspection and Test Plan).

Fit aluminum flashing with sealant to terminations of the membrane on walls.

Install polystyrene boards in a neat tight fit.

Install geotextile layer.

Install gravel layer and concrete pavers in accordance with the drawing layout.

Method Statement for Waterproofing Using Cementitious Membranes – Wet Areas such as Bathrooms, Lift Pits, Terraces, Pantry, etc.

Material:

Acrylic cementitious waterproofing membranes

Procedure:

For Concrete Base Surface Preparation:

Structural cast in-situ reinforced concrete slab dry, smoothly finished, and, clean from construction debris.

Concrete upstand shall be dry, clean, and smoothly finished.

CMU (Concrete Masonry Units) upstands must be properly plastered and, smoothly finished.

Establish a 50 x 50 mm mortar canstrip at junction lines between horizontal and, vertical surfaces.

Upstand edge lines should be slightly chamfered and smoothly finished.

Set up mortar cones around the base perimeter of service pipes protruding from the concrete slab.

Prepare the concrete threshold at the wet areas door entrance minimum of 80 mm height, according to actual site conditions. This will serve as a barrier during water testing after the waterproofing application.

Membrane application:

The surface to be coated with acrylic cementitious waterproofing membranes must be slightly damp to ensure a firm enduring bond to the substrate.

Temperature condition:

Acrylic cementitious waterproofing membranes shall be used when the ambient temperature is above 5°C.

In hot water, areas to be coated shall be shaded from direct sunlight.

Mixing:

The acrylic cementitious waterproofing membranes shall be mixed in a clean container.

The powder shall be added slowly to the liquid component. Utilizing a slow-speed drill with a suitable mixing head, mix for a minimum of 2 minutes until a homogenous lump-free consistency is obtained.

Application:

Two coats of acrylic cementitious waterproof coating, at the rate as per the manufacturer’s recommendation complete with mesh reinforcement strip at junction lines between horizontal and vertical surfaces and around pipe penetrations.

Curing:

As per the manufacturer’s material specification

Test:

Water tests should be conducted for the completed areas for a period of a minimum of 24 hours prior to the application of the tiling and finishing items.