The "depth" of waterproofing refers to either the coating thickness applied to a surface or the excavation depth required to protect a foundation from underground water. The exact measurement depends entirely on the specific application.
Waterproofing thickness depends heavily on the application and the material used. For liquid-applied membranes in wet areas (like showers and bathrooms), aim for a dry film thickness (DFT) of 0.6 to 1.5 mm. For exterior surfaces, high-traffic decks, or heavy-duty environments, the requirement increases to 1.5 to 3 mm.
Avoiding common basement waterproofing mistakes can save you time, money, and frustration down the road.
Most are about 2 to 4mm thick. There are essentially 2 types of membranes, sheet based membranes and liquid applied membranes. Ideally, a waterproofing membrane should be strong, flexible, tear-resistant and elastic so that it can stretch to cover cracks and also move with the building.
Yes, 7 mil is thicker than 5 mil.
10 mil is thicker than 4 mil.
In general, polyurethane waterproof coatings are one of the most durable options since they are resistant to chemicals and can withstand extreme temperatures and UV exposure.
1/2-Inch Plywood: Commonly used for residential roofing with rafters spaced 16″ apart. It is acceptable under many codes but may flex under heavy snow or foot traffic. 5/8-Inch Plywood: Offers better support and is often preferred in areas with snow load or roofs supporting solar panels.
Most water-based membranes require a final application rate of approximately 1.5L per per square meter. This is often achieved with two coats, however, as application techniques and membrane viscosity vary, you may need to put on further coats to achieve that type of usage.
Waterproofing typically lasts 10 to 25 years, but the exact lifespan varies significantly by the application. Foundation and basement systems can endure for decades with proper maintenance, while exterior coatings and temporary sealants degrade much faster.
Materials that are considered 100% waterproof typically include synthetic polymers and coated fabrics that create an impermeable barrier to water, such as PVC (vinyl), silicone-coated nylon/polyester (silnylon), rubber, and polyurethane laminates. These materials do not allow water to pass through, making them ideal for tents, rain gear, and coverings.
Only a licensed waterproofing contractor is legally allowed to perform waterproofing work in residential construction or renovation projects where the value of labor and materials exceeds $5,000. Even for smaller jobs, insurance implications and resale requirements often demand licensed involvement.
Grade 1b – No seepage. Damp areas from internal and external sources are tolerable. Grade 2 – No seepage is acceptable. Damp areas as a result of internal air moisture/condensation are tolerable; measures might be required to manage water vapour/condensation. Grade 3 – No water ingress or damp areas is acceptable.
The walls of the shower area must be waterproof not less than 1800 mm above the floor substrate (see Figure 10.2.
The 90/10 rule requires that “90% of all thickness measurements should be greater than or equal to the NDFT (or, Nominal Dry Film Thickness) and none of the remaining 10% measurements should be below 0.9 x NDFT". Performed manually, the process can be confusing and requires several manual calculations.
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Materials that do not allow water to pass through are called impermeable or non-porous. Because they lack connected pores or holes, they block liquids entirely.
The most affordable waterproofing method is the use of basic acrylic waterproof coatings. However, these coatings may not last as long as premium waterproofing solutions.
20 mil is equal to 0.02 inches.
4 MIL - Heavy duty protection when packaging nails, screws & heavy metal parts. 6 MIL - Extra heavy duty protection against punctures and tears on bulky items or items with sharp corners.
No. A 10 mil measurement is thicker.
12 mil is thicker.
Ziploc bags range from 1.5 to 3 mils in thickness depending on the specific type. A "mil" is equal to one-thousandth of an inch (0.001 inches), with a higher number representing a thicker, more durable bag.
200 mils is equal to 0.20.20.2 inches (or 5.085.085.08 millimeters).