Liquid Rubber Waterproof Sealant Kit - Durable Multi-Surface Sealant

In this review of the Liquid Rubber Waterproof Sealant kit the bottom line is straightforward: this kit is for homeowners and tradespeople who need a long-lasting, flexible waterproof membrane for roofs, foundations and other problem areas. The single biggest reason to buy is the kit format that combines a full 5 gallon sealer with caulk and seam tape so you get a coordinated system to stop leaks and handle movement; this review focuses on real-world application, coverage, and durability rather than marketing claims.

Key Features

• Complete kit: Includes one 5 gallon pail of waterproof sealant, a 4 pack of 10.2 oz caulk, and one 4 in x 50 ft seam tape to address seams and penetrations.
• Multi-surface use: Formulated for flat and metal roofs, sloped roofs, planter boxes, foundations, sheds and common building materials like wood and concrete.
• High flexibility: The cured membrane offers over 1000% elongation so it stretches with structure movement and resists adhesion failure.
• Coverage guidance: Coverage is clearly stated for vertical and ponding surfaces so you can estimate coats: roughly 1 gal/30 sq ft for vertical and 1 gal/15 sq ft for ponding areas.
• Water based and low odor: The formula contains no solvents or VOCs so it can be used indoors or outdoors without special breathing apparatus.
• UV stable finish: The membrane resists sun degradation which helps preserve the waterproofing over time.

Who It's For

This kit is best for DIYers, roofers, and property owners tackling leaks on flat roofs, metal roofs, planters, basements and similar substrates who want a single product family to coat surfaces and seal joints. The included seam tape and caulk make it practical for handling joints, vents and penetrations where movement is expected.

Those who should look elsewhere include people needing a one-coat quick dry cosmetic paint, or projects that require specialized chemical resistance outside the described uses. Also, if you need very high initial coverage per gallon without multiple heavy coats, consider alternatives designed for single-coat film build.

Pros & Cons

Pros

• Effective waterproofing across many surfaces when applied per coverage guidance.
• High elongation and UV stability give a durable, flexible membrane that resists cracking.
• Low odor, water based formula makes application safer indoors and outdoors.
• Kit format supplies caulk and seam tape so users can create a more complete system.

Cons

• Requires multiple heavy coats to reach recommended mil thickness, which increases labor and drying time.
• Some users report variable drying in certain conditions, so climate and surface prep matter.

Specifications

Our Verdict

The Liquid Rubber kit is a practical value for anyone needing a durable, flexible waterproof membrane and a coordinated set of accessories to treat seams and penetrations. It delivers long-term sealability and UV stability, but be prepared to apply multiple heavy coats and allow adequate dry time. For roof and foundation repairs where movement is expected, the kit is a sensible investment for durability and ease of use.

Frequently Asked Questions

How many coats are required?
Vertical surfaces typically need 3-4 heavy coats to reach a 30 mil membrane; ponding surfaces usually require 4-5 heavy coats to reach 60-80 mil.

Is this safe to use indoors?
Yes, the product is water based with no solvents or VOCs and low odor, so it can be used indoors without special breathing apparatus.

Can the seam tape handle movement?
Yes, the kit includes 4 in x 50 ft seam tape recommended for bridging joints and seams where movement may occur to create a more bulletproof system.