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SealBoss Curtain Injection

Bladder / Curtain Injection – Curtain Wall Grouting Method

Introduction

Bladder or Curtain Injection is a specialized method used to seal below-grade block and concrete wall structures by forming a protective membrane through the permeation and consolidation capabilities of hydrophilic and hydrophobic grouts. Utilizing the SealBoss Leak Sealing Cube for training, contractors gain an intricate understanding of the injection process and grout behavior. This hands-on approach, which allows observation of the process from the soil side of the wall, prepares professionals for effective on-site applications, ensuring thorough and lasting waterproofing solutions.

Curtain Injection Injection Training with a SealBoss Leak Sealing Cube

The primary objective of the curtain injection method is to effectively seal below-grade block and concrete wall structures by leveraging the advanced membrane-forming, permeation, and consolidation capabilities of hydrophilic and hydrophobic injection grouts. This process ensures long-lasting waterproofing, even under challenging conditions where traditional methods may fail.

This specific training for curtain injection is conducted using the SealBoss Leak Sealing Cube, a sophisticated version of our mock-up designed to replicate real-world scenarios. The Cube offers contractors and engineers a detailed insight into the intricacies of the injection process and the dynamic behavior of chemical grouts under varying conditions. Equipped with Plexiglas cross-sections, the Cube allows trainees to observe the injection process from the ‘other side’—a perspective typically hidden during actual on-site curtain grouting. This unique visual aid is invaluable in understanding how the grout permeates and consolidates within the substrate, forming an effective waterproof membrane.

By closely following the grout’s interaction with the positive soil-side behind the wall, trainees develop a comprehensive understanding of the injection method and technology. This hands-on experience is critical for mastering the application of these advanced materials, ensuring successful outcomes in both routine and complex waterproofing projects. The ability to visualize and understand these processes in a controlled environment prepares professionals for the challenges they will face on the job site, ultimately leading to more effective and reliable sealing solutions in the field.

Procedure Outline

Identify the water source and pattern of moisture intrusion. Most block, stone, and brick leaks are caused by failed positive side membranes. Block walls are often unfilled which also creates voids and pockets for water intrusion. Drill Grid Pattern Drill 3/8 or 1/2 inch holes along the water marks at 2 feet intervals. Moving up the wall, continue to space the holes at 2 feet intervals creating a grid pattern of injection holes as seen in the image. These drill holes are to penetrate the substrate at full depth creating a channel in the wall through which chemicals can be injected.

Packer Install

Once the grid pattern is created, mechanical packers may be inserted into each one. In the case of block walls that are not filled adequately, longer packers are recommended providing a full length channel which ensures that material reached the back side of the wall. it is not recommended to simply fill the blocks with materials – block wall curtain injections require material travel through the entire wall. In the case of older and disturbed stone or brick structures, however, it is also common to inject the structure itself as seen to the right.

For high volume applications, Plastic Button Head Packers are available.

Injection Products and Pumps

In today’s focus, we highlight the SealBoss ® 1510 Curtain Injection Foam and SealBoss ® 15X Accelerator. The single component SB 1510 chemical injection grout is catalyzed with SB 15X Accelerator at variable percentages to either create low foaming expansion or high foaming expansion properties, with the accelerator dosage varying between 2 % to 25 %.

epending on site-specific needs, a selection of products is available, including the hydrophobic SealBoss 1510 / 1570 Foam, SealBoss FlexGel hydrophilic polyurethane gel, or SealBoss® 2400 SLV acrylic gel, are available.

Application Considerations

Because backfill and soil consolidation behind the structures are often unknown, applicators must monitor flow rates and material consumption closely.

Given the often unpredictable nature of backfill and soil consolidation behind structural walls, it is imperative for applicators to closely monitor flow rates and material consumption. In cases where significant voids are expected, the use of expansive hydrophobic polyurethane grout, such as SealBoss® 1510 Water Stop Foam, is recommended. This approach effectively fills large voids, creating a solid mass that can serve as a stable foundation for subsequent hydrophilic gel injections if necessary.

The Stage Grouting Technique

The stage grouting technique is often recommended in such situations. This method involves injecting the product in measured stages with reduced volumes. Each stage is given adequate time to react and form a natural barrier, prior to injecting the next grout stage. This strategic layering and controlled application enhances the overall effectiveness of the grouting process, ensuring comprehensive coverage of product along the outside of the wall and optimal stability.

For in depth training training on specific injection techniques or on-site assistance, please reach out to your SealBoss® Technical Representative or contact the main office at 714-662-4445 for further support.

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Curtain / Bladder Injection Products

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Injection Brochure

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Curtain

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Curtain Injection In Pictures

Curtain Injection in Pictures

And Podcast

Curtain / Bladder Injection - Curtain Wall Grouting Method

Water intrusion is a persistent challenge for below-grade concrete structures, where traditional patching and surface sealers often fall short. The failures of these surface-applied remedies—such as patches, liquid sealers, and membrane applications—stem from their inability to address the root causes of leaks. These methods provide only temporary relief, leaving structures vulnerable to recurring hydrostatic pressure and ongoing water damage.

Curtain wall grouting, including advanced techniques like curtain and bladder injections, offers a reliable, long-term solution to these challenges. Unlike surface treatments, these methods work by creating a robust waterproof membrane and water barrier behind the structure. This approach not only seals cracks and cold joints from within but also fortifies the structure against future water intrusion.

By injecting specialized grouts through the structure to form a protective layer on the positive side, curtain injection ensures a comprehensive and lasting seal. Whether applied through stage grouting or other targeted injection methods, this professional approach delivers durable protection, minimizing service interruptions and maximizing cost-effectiveness in the long run.

Curtain / Bladder Injection is the Reliable Way to Waterproof Your Below Grade Concrete Structure Permanently

Why Patches and Liquid Sealers Often Don’t Stand the Test of Time

Experiencing the frustration of failing patches and paint applications on damp, actively leaking, below-grade structures is something many of us can relate to.

These are typically failed attempts to block hydrostatic water intrusion using surface-applied remedies that serve as temporary solutions at best.

Interior patches and membrane applications, while seemingly addressing the problem, often don’t tackle the root cause and rarely provide a lasting waterproofing resolution.

A Professional Approach to Curtain Injection:

Sealing Cracks Permanently and Establishing a Waterproof Membrane and Water Barrier behind the Structure

Water leakage via cold joints, cracks, and other irregularities in concrete can frequently only be effectively and permanently sealed using advanced injection techniques, such as curtain, bladder, and stage grouting injection methods.

The SealBoss Injection Product offers a professional solution to these issues, filling and sealing the cracks from the inside out. This product is injected through the structure, forming a membrane on the structure’s positive side, thus providing a more effective and lasting waterproofing solution.

The Art of Stage Grouting Technique

In complex grouting scenarios, the stage grouting technique is often the favored approach. This process entails a strategic series of injections carried out in a staged manner, utilizing lower volumes of product in each application.

Each stage of this meticulous process is allowed sufficient time to react, allowing the grout to solidify and establish a natural barrier before proceeding with the subsequent stage of grouting. This carefully phased and controlled deployment not only elevates the overall efficacy of the grouting operation but also ensures thorough and consistent coverage along the exterior of the wall.

Comparative Cost Analysis of Injection Grouting Sealing Methods

Understanding the financial impact of various sealing techniques is essential for making cost-effective decisions. Below is a comparison.

Crack Injection

Direct Costs: Moderate for materials and labor, product is injected directly into the cracks, joints, and voids. Low for equipment.
Indirect Costs: Minimal, as the method is fastest and causes little service interruption.

Curtain Grouting

Direct Costs: Higher for materials and labor, product is injected through the structure into the substrate behind, which results in higher material consumption. Packers are set in distinctive patterns. Moderate for equipment.
Indirect Costs: Higher, due to the lengthier process of preparation and product pumping, which can lead to more significant service disruptions.

Links

Curtain / Bladder Injection Products

Professional Polymers

Premium Packers

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SealBoss Injection Pump Systems

Mockups
Curtain Wall Grouting | Negative Side Injection Waterproofing

"The Mockup is Worth its Weight in Gold"
Technical Podcast for the Infrastructure Repair Industry

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Blanket Injection – Horizontal Waterproofing

Blanket Injection

Horizontal Waterproofing Injection Technique

What is Blanket Injection?

The process of Blanket Injection or Horizontal Curtain Injection involves injecting a water activated, single component polyurethane foam or gel resin into the space between a slab and the supporting soil substrate for the purpose of providing a waterproofing barrier. The objective is to prevent erosion and water seepage from below the slab through any cracks and joints.

Blanket Injection and Curtain Injection are considered primarily waterproofing injection methods and should be performed using chemical grout resins with excellent penetration and moderate gel time properties. With accelerator controlled systems, gel times are adjustable to suit the individual conditions on the jobsite.

If left untreated, cracks and joints in concrete slabs permit water migration into the structure driven by hydrostatic pressure — leading to rebar corrosion, mold, and further destruction of other infrastructure, including damages to walls, doors, furniture, equipment and more.

Void Fill and Blanket Injection with SealBoss 1510 Polyurethane Chemical Grout

Scope

A mixed-use, commercial and agricultural building in Oklahoma had a water pipe burst under substantial hydrostatic pressure, causing significant erosion under the concrete floor with the potential for subsequent water ingress through cracks and joints throughout the whole mixed-use building.

Solution

The proposed solution was to fill the voids and to create a waterproof barrier und the slab using the Blanket Injection Method.

Filling of the voids and creating waterproof barrier underneath the slab was achieved by using an expandable, water-activated, single component hydrophobic chemical injection grout with excellent void filling, penetration, and waterproofing properties.

The gel time needed to be adjustable for shorter and longer gel times. The product had to react on contact with moisture, and the expansion pressure had to be controllable, to avoid any lifting of the slab.

SealBoss 1510 with SealBoss 15X Accelerator were the products of choice.

Overview of Repair

Injection packers were set in a grid pattern, roughly a three foot on center grid with an expected travel of one and a half feet in all directions from the point of injection. The expected travel would be accomplished by varying the SealBoss 15x accelerator/catalyst percentage between 5% and 20% by volume based on real time behavior of substrate.

Monitoring

Since this application was performed during a contractor training, travel of foam was monitored in three separate ways to visualize the effectiveness of the repair.

Firstly, the removal of an adjacent packer creates a control hole for the successful spread of injection grout, and an immediate path of least resistance, allowing for some displaced substrate and water to escape from the open hole rather than building up and creating blockages.

In addition, a Borescope and a Thermo-Imaging Camera were used to visually enhance the training. However, neither a borescope, nor a thermographic camera are essential tools for successful blanket and curtain injection procedures.

The borescope was used to get a visual of the void prior to injection and to observe the travel of foam during the injection process. The thermo-imaging camera was utilized during the injection process to visualize the spread of the expanding exothermic injection grout.

Find more information on the use of thermography for injection process monitoring here.

Injection Process

During the blanket injection process, the resin was injected into each packer in up to one-half gallon intervals with varied Sealboss 15X catalyst percentages added.

During the Injection it was determined that all perimeter packers in the injection grid would be injected with 15% to 20% SealBoss 15X catalyst added. This percentage results in a more aggressively reacting foam, creating a dam like structure between the slab and substrate, specifically along the perimeter of the injection area. While injecting the perimeter packers the adjacent interior packer was removed to monitor volume of resin needed to make real time adjustments to injected resin volume.

Once all perimeter packers had been injected, interior packers were injected working towards the center of the room injecting in intervals and monitoring resin flow.

The interior packers of the grid were injected with a slower, less reactive foam, catalyzed at a ratio of only five to ten per cent, resulting in a longer gel time, decreased expansion speed and reduced expansion rate — allowing the chemical injection grout to travel much further during injection.

With a varying void depth of up to one inch in an 18’ x 20’ area, 20 gallons of SealBoss 1510 and 2 gallons of 15x Catalyst were used.

Materials and Tools Used

Learn More

Please don’t hesitate to call us at 714-662-4445 with any questions, or request to be contacted here, we look forward to helping you find a solution. On-site support from knowledgeable and experienced technical reps is available upon request. Check out our Crack Injection Kits.

Note: For slablifting and structural void filling applications please cross-reference dry-reactive, moisture independent, fast reactive two component lifting and void fill foam SealBoss 1640

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