Blog

What This Covers

This guide walks through the use of self-adhering sheet waterproofing systems, particularly those based on modified bitumen. It also includes helpful guidance on related prep work, material coordination, and what to expect during installation and quality assurance.

Before You Begin: Project Coordination

Before installation starts, it’s a good idea to hold a prep meeting onsite. This meeting helps everyone align on details like surface prep, substrate readiness, curing times, weather considerations, and installation methods. It’s also the time to walk through any unusual conditions or transitions that might need special attention.

Getting the Details in Place

Ahead of the install, product documentation and shop drawings should be shared with the team. These should outline where the waterproofing will go and include details for things like joints, corners, penetrations, and tie-ins. Installation instructions and performance expectations should also be made available to everyone involved.

Sample Warranties

Warranties can vary, but most systems include a materials-only warranty that covers premature failure or issues related to watertight integrity. Keep documentation on hand in case you need it later.

Choosing the Right Team

Proper installation starts with the right crew. The system should be installed by professionals who have been trained and approved by the waterproofing manufacturer. Their experience helps ensure that everything goes down correctly the first time.

Timing and Conditions Matter

Waterproofing systems should be installed during the right temperature window, based on what the manufacturer recommends. It shouldn’t be applied to damp surfaces, nor during rain, snow, or fog. Good ventilation is also essential during application.

Material Coordination

To ensure everything works together seamlessly, all materials—membranes, primers, sealants, and flashing components—should come from the same system provider. This helps reduce compatibility issues and ensures the components are designed to perform as a unified system.

Prepping the Surface

Proper surface preparation is critical. Substrates must be clean, dry, and free of debris, coatings, or contaminants. This includes removing form release agents, paints, or grease, and filling any gaps, voids, or bug holes. Joints and cracks should be treated according to best practices before waterproofing goes down.

Corners and penetrations require special treatment—typically with a combination of pre-cut membrane strips, liquid flashings, or fillets to ensure a watertight seal.

Installing the Membrane

Primers or conditioners are usually applied to help the membrane bond. Sheets should be accurately aligned with consistent laps and tight seams. Any wrinkles, blisters, or fishmouths should be corrected right away, with patches extending well beyond any repaired areas.

Membrane systems often include protection layers. These are installed immediately after the membrane to shield it from damage. In some cases, insulation boards can serve as the protection layer, especially on vertical surfaces.

Installing Insulation

Where required, insulation should be cut to fit tightly around projections. On walls, it’s typically adhered with approved tapes or adhesives. Once installed, it should be protected from the elements until covered by the final finish or cladding.

Protecting the Work

Unprotected membranes should not be walked on or exposed to heavy equipment. Until the system is covered by permanent construction, temporary protection should be used to prevent UV damage or weather exposure.

If any part of the system is damaged or improperly installed, it should be corrected right away—this includes reapplying the membrane and re-flashing as needed.

Cleanup and Final Touches

At the end of the job, any spills or overspray should be cleaned up using methods that won’t damage adjacent finishes or surfaces. Keep the work area tidy, and document the installation as needed for warranty and closeout.

---

Reference Standards

The guidance above is informed by widely recognized industry practices and standard installation procedures. Where applicable, it aligns with commonly followed benchmarks in the field, including best practices established through organizations like ASTM.

Frequently Asked Questions (FAQ) About Self-Adhering Sheet Waterproofing

What is self-adhering sheet waterproofing?
It’s a type of waterproofing membrane that comes in rolls and sticks directly to the surface without the need for torching or hot asphalt. It forms a continuous barrier that helps keep moisture out of critical areas like foundations, walls, and below-grade slabs.

Where is this type of waterproofing typically used?
You’ll usually find it used on foundations, plaza decks, tunnels, below-grade walls, and in any location where moisture needs to be kept out long-term. It’s especially useful in areas where a seamless, flexible membrane is needed to accommodate movement or settle around irregular surfaces.

What surfaces need to be prepped before installation?
Concrete and other substrates must be clean, dry, and free from dust, oils, coatings, or curing agents. Joints, cracks, and voids need to be filled and treated first. Corners, penetrations, and terminations also require special prep to ensure a tight seal.

Can you apply this in any weather?
Not quite. You’ll want to avoid rain, snow, or even fog during installation. The surface must be dry, and temperatures need to fall within the range recommended by the product manufacturer. Some systems are made for colder temperatures, but only use those when conditions actually call for it.

What should be done after the membrane is installed?
Protection is key. A protection course or insulation board should be applied right away to shield the membrane from traffic, UV light, and other construction activities. Exposed membranes should never be left out too long, especially in high-traffic or outdoor environments.

What happens if there are wrinkles, tears, or air bubbles?
They need to be addressed immediately. Wrinkles and blisters can be slit, flattened, and patched with additional membrane. Tears or areas that don’t fully adhere should be patched with an overlap that extends well beyond the damaged section.

Do I need special training to install this system?
Yes, installation should be handled by trained professionals who are familiar with the system and approved by the product manufacturer. Proper training helps ensure the system is installed correctly and covered by warranty.

Is a primer always required?
Most systems do require a primer or surface conditioner to help the membrane bond with the substrate. The type used depends on the surface and environmental conditions, so it’s best to follow the system manufacturer’s recommendations.

Can this system tie into other waterproofing materials?
Yes, but the transition points must be handled carefully. Auxiliary materials like liquid membranes, flashing strips, and sealants are often used to create a continuous, watertight connection between different systems or components.

How long is it covered under warranty?
Warranties can vary, but a standard materials-only warranty often covers around five years. Make sure to check the details provided by the manufacturer and keep proper documentation.