The purpose of the method statement for application of waterproofing is to prevent the water to percolate or penetrate into any underground concrete members. When the water penetrates into the sub-grade concrete-like foundation such as mat foundation, footing, tie beam, etc. the steel reinforcement that embedded in the concrete would corrode due to a chemical reaction caused by water and the structure would eventually fail.
Application of waterproofing especially for large structures would have to be strictly supervised by a quality engineer in order to prevent failure of application or nonconformity to the quality procedure.
In this method statement for application of waterproofing membrane, we’ll be going to use the membrane type waterproofing, this type of waterproofing is advisable for structures like high-rise buildings which has a deeper foundation where water pressure is extremely high.
Here is the method statement for application of waterproofing membrane.
1. Title
Method Statement for Application of Waterproofing Membrane
2. Purpose and scope
The purpose of this method statement is to describe the measures and ways of the proper application of waterproofing membrane in our project. Work shall be carried out as per the drawing and project specifications.
3. Work procedure
3.1 Work preparation and application of primer:
3.1.1 Any undulations or protrusions on the surface would be removed in order to obtain a smooth surface. The surface must be thoroughly cleaned and free from dust, dirt loose materials, oil or grease.
3.1.2 50x50mm size fillet made of cement-sand (1:3) mix would be placed along corners of walls or neck columns and any other junctions.
3.2 Application
3.2.1 For horizontal waterproofing membrane application. Two layers of 4mm thick modified bituminous membrane shall be laid fully torched on blinding concrete with a minimum of 100m end laps and 150mm side laps.
3.2.2 The blinding surface shall be primed with the primer recommended by the manufacturer of the membrane prior to placing the membrane. Prior to succeeding works, the applied primer shall be inspected by the Engineer 24 hours after the placement.
Primer Application
3.2.3 Waterproofing membrane installation shall be performed using cylinder-fed propane gas torch, trowel to seal the seams of the membrane, and knife for cutting.
3.2.4 The membrane is then placed in the correct torching position then re-rolled for about half of its length without changing its orientation.
3.2.5 The membrane is then unrolled again and torched on pressing the melted area against the substrate.
Membrane Application
3.2.6 Repeat till the entire length of the membrane is bonded firmly onto the surface then the second membrane is laid in the same way with an overlap of 150mm at the end and 100mm at the side.
3.2.7 An extra length of a minimum of 300mm of the horizontal membrane shall be left to carry up the vertical surface to maintain continuity of the membrane and be protected as above.
3.2.8 For vertical application, two layers of 4mm thick modified bituminous waterproofing membrane shall be applied to all vertical surfaces of gunited shoring or blockwork wall.
3.2.9 Before applying the waterproofing membrane, concrete surfaces shall be primed with primer recommended by the manufacturer of the membrane but then again it should be inspected by the Engineer 24 hours after the placement.
3.2.10 The extra portion of 300 mm of the horizontal membrane left shall be turned up and wrapped on to the vertical primed surfaces. The continuity of the membrane shall be maintained by minimum laps of 150mm.
3.2.11 The membrane on the exposed external vertical surfaces shall be carried up to a minimum of 150 mm above the finished ground level (i.e. sidewalk, parapet, etc.) and tucked into a continuous groove provided for the same and secured firmly with approved sealant/mastic recommended by the manufacturer of the membrane.
3.2.12 The membrane fixed on the gunited or concrete wall shall be protected from any damage due to rebar fixing, formworks, concreting of the raft, retaining wall works with approved type protection board fixed to the membrane.
3.2.13 All areas of the membrane exposed above ground shall be protected with appropriate flashing.
3.2.14 Inspection would be submitted for approval of the Engineer.
3.2.15 Before fixing of steel reinforcement for the foundation, the membrane shall be covered by one layer of polythene sheet and poured with 50 mm thick layer of cement-sand screed.
Polythene Sheet Above Membrane
4. Safety
- All works shall comply with safety procedures or instructions as set out in the project safety plan and municipality rules and regulations. All safety recommendations as advised by the approved sub-contractor.
- Basic PPE to be worn by all staff or laborers.
- Provide lighting when working at night.
Note:
Please ensure that all safety precautions are addressed on this method statement for the application of waterproofing membrane. And ensure all the attachments are attached before submission to the engineer for approval.
5. Equipment and tools
- Bobcat or JCB
- Wheel borrow
- Metal tape
- Torch
- knife
6. Materials and references
- Modified Bitumen Membrane
- Specification Section – Waterproofing
- Drawings
Did you use the method statement for application of waterproofing membrane in your project? If yes, please comment down below.
If you have any suggestions and comments on the above method statement please feel free to leave your reply below.
Thanks!
Hi,
Thanks for sharing this useful information and ideas with all of us. Keep sharing more information. This is really help to us. NVLN CONSTRUCTIONS PVT LTD is a provider of end to end building Restoration services to help clients to improve safety and longevity of structures. We have been relentlessly working on providing services in concrete repairs & rehabilitation works.
I am requesting for waterproofing materials specification and how can I find out the work quality at site, for example as per the dwg the contractor should apply 2 coats of primer in this case how we can ensure that they did 2 coats? Pls reply by email
Ans: You can ensure by asking them to submit an Inspection Request to you. Each application there should be IR in order for you to verify. It is just how simple it is.
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I will be posting more informative videos there.
Thanks,
Greetings!
Can you please help me sharing the copy of Method Statement – JSA/Risk assessment for Application of Waterproofing including bitumen.
Mainly from safety view to protect leakage and in case of leakage what are the immediate actions that should be taken.?
Thanks and Best Regards
[email protected]
You might want to say “to prevent the leakage,” well to ensure that before placing the screed you should make sure that inspection would be carried out. Pre task briefing would be conducted for the waterproofing so that workers would be aware of what purpose a waterproofing is.
If there is leakage you have to hire a subcontractor to do the rectification. So before it happens I advise you to take extra care especially for those projects near creek or seashore.
Good topics for each engineer.
Can we find some material related to Combo water proofing ?
Hi Noel Mades,
I saw your post and you have replying all the answers with good solution which are very helpful and keep going.. I have one question to ask and require answer for this as I am working on a project where we have to do internal waterproofing work of sewage tank since there are many repair work inside and our team has already done repair work but we are planning to start blasting of all the internal tank with cleaning and now after this we want to carry on with whatever repair which was been done before blasting to apply repair mortar and than do 1st coat of primer followed by membrane coat I just want to know can we follow this will there be any problem please suggest.. I am waiting for you reply
Paresh Bandekar
Hi Paresh,
Make sure that you apply the membrane underside of the tank (before casting the tank). If you apply the waterproofing membrane on the tank (after casting) it will not work. And don’t rely on waterproofing membrane itself you can use injectable waterproofing.
If you have any more questions, please let me know.
Regards,
Noel
Dear Noel,
Thanks for all the posts. It is really helpful.
How can I contact you? Are you still in the UAE?
Regards,
Schalk
Hi Schalk,
Welcome and thanks too for being here.
You can contact me at the contact form of this blog or email at [email protected]. Yes, I’m still here in Dubai.
Regards,
Noel
Greetings!
Can you please help me sharing the copy of Method Statement – JSA for Application of Waterproofing Membrane, including bitumen.
Thanks and Best Regards
Satyabrata Tripathy (S.B)
email : [email protected]
NVLN CONSTRUCTIONS PVT LTD is a provider of end to end building Restoration services to help clients to improve safety and longevity of structures.We have been relentlessly working on providing services in concrete repairs & rehabilitation works.
Great post. It is much helpful for us. Being a waterproofing contractor we are so happy to get this blog.
Thanks
SR Buildcare Tech
Welcome and thanks for stopping by.
Excellent post! I completely Understand and I have been following your blog for quite some time and I like the content that you share with your readers. We also provide waterproofing membrane service and complete construction material in Singapore.
Thank You.
Can you please mail me the sectional detail for waterproofing in this senario?
also what is the difference in the procedure in waterproofing has to be done over a pile cap?
Hey there! Someone in my Facebook group shared this website with us so I come to give it a look. I’m definitely loving the information. I’m book-marking and will be tweeting this to my followers! Superb blog and terrific style and design.
Thanks a lot Ima.
Hello.
May i know what will be the resources of Workforce in waterproofing
Hi Afnan,
Our waterproofing subcontractor has 1-Site Engineer, 1-Foreman, 3-Applicator( holding the torch) and helpers.
Hoping the above answers complies with your question.
I am also a civil engineer by Profession working as a Quantity Surveyor in Dubai since 5 months . thank you posting such excellent Method statement for Water- proofing,
Welcome and thanks for stopping by.
This website was… how do you say it? Relevant!! Finally I have found something that helped me.
Many thanks!
Hi.
May i know how to remove rusty dust stained on the waterproof membrane? it caused from welding work/steel cutting work nearby.
is it by using water jet will affected the membrane?
Thanks in advance
Hello,
I did not experience that kind of scenario. They should have protected the membrane before welding works. I suggest asking the supplier of waterproofing on what is the best solution on that issue.
Regards,
I hadn’t didn’t know about safety in waterproofing before reading this article. It sounds like the right equipment and supplies is crucial though. I’m glad I now know about PPE that needs to be worn by all staff, like you said. Do these same safety precautions need to be taken for basement waterproofing?
May I know if there is any option not to use domestic cylinder for water proofing? Coz, in my site the consultant raising a lot of issues with regards to the use of domestic LPG cylinder.
We’ve been using it in our Abu Dhabi and Dubai Project. Tell your consultant to accept the Job Safety and Environmental Analysis and Risk Assesment. There you can reduce the risk to an acceptable level by applying control measures.
Great Mr . Noel Mades
When we do the water testing in this methodology I mean we can do this after applying of membrane or after screeding works.
After application of membrane.
Dear Noel,
I would like to know if the Method Statement for SBS Membrane for decks should be made separate from the entire system within the section of the specification… i.e. XPS Insulation Boards, Geotextile, Ballasts, and Concrete Pavers on pedestals, which are to be installed subsequent to the membrane.
TAR.
Dear Noel
Do you have any method statement for water proofing top of the concrete floor?
BR
Kamalaraj.S
Hi Kamalaraj,
Yes, we have.
Noel
Dear Mr. Mades. Please, could you let me know what CCTA is? The contracts managers on site in Mauritius have asked me to provide CCTA for cement slurry waterproofing system/s
Regards Andrew
Dear sir,
Let me know how to ingress gas cylinder pressure?
Can you give tools details?
Hi Sir, pls. suggest me, we constructed an RCC tank for storage purpose for poly aluminum chloride, which kind of treatment or application of paint can be used over the wall of tank to protect against chemical reaction with concrete? Pls. share with me the answer on my email.
Hi, do you have a topic about the hazard in various types of work specifically in construction industry, like waterproofing work hazards. thank you.
Hello Jayn, I’ve written a blog post about Risk Assessment and JSEA and one ebook, you can find it here. Please watch my upcoming book about that.
Why does the substructure require 2 layers of waterproofing. Isnt 1 layer enough?
It depends on the criticality of the structure. Most commonly one layer is ok.
The product effectively penetrates, seals, waterproofs and protects new wood and aged wood while resisting moisture penetration, and subsequent rotting and decay, thus protecting against cracking, splitting and warping of wood.
Thanks Mr.noel.
Dear Noel,
Do you have a method statement about the waterproofing of dewatering wells?
You can check my ebooks I wrote the title of Method Statement and see if it fits to your requirement.
Thank you.
You’re welcome.