Garage Waterproofing: Know these Before Starting

Written By Adam Paul – Waterproofing Expert

Garage waterproofing is applying waterproofing membranes to seal the garage floor, walls, and roofs to prevent water from leaking and damaging the garage and its components. Installing a waterproofing membrane on the garage is highly beneficial for both structural and functional performance.

To waterproof a garage, you can install these 4 main waterproofing membranes: polyurethane, EPOXY, acrylic, and cementitious by following the recommended method by the Aqviz experts. You should waterproof masonry garage floors to prevent water seepage through the slab. Not only that you should waterproof the garage openings, such as doors, windows, and openings, to prevent water leakage into the garage. As well as we highly recommend that you use sealing equipment, such as weatherstripping, to prevent water leaks through the openings.

For better garage waterprotection, you can install waterproof garage walls, waterproof the garage walls, use waterproof paints and sealants. After the garage is waterproof, it should be protected properly to prevent water damages prolong. So contact Aqviz experts for any garage waterproofing project we will help you to do it next level.

What is Garage Waterproofing?

Garage waterproofing is applying waterproofing membranes to seal the garage floor, walls, and roof to prevent water from leaking and damaging the garage and its components. The advantages of garage waterproofing are preventing the growth of mold and mildew, increasing skid resistance, preventing chemical damage to the floor, safeguarding the foundation, helping to prevent the belongings from getting wet and rusting, and increasing property value.

What are the 6 Benefits of Garage Waterproofing?

Installing a waterproofing membrane on the garage is highly beneficial for both structural and functional performance. These are the 6 benefits of garage waterproofing using a proper waterproofing membrane.

Control the moisture in the garage: Proper garage waterproofing helps prevent groundwater, rainwater, and wash water from penetrating concrete slabs and masonry walls. This control reduces capillary action and hydrostatic pressure, which helps keep the garage dry even during heavy rainfall of 50-100 mm (2-4 in).
Increase structural durability: Garage waterproofing helps protect concrete and embedded steel reinforcement from continuous moisture exposure. This protection prevents rebar corrosion, concrete cracking, and surface spalling, which helps increase the structural service life by 10-20 years.
Prevent mold and mildew growth: Waterproofing helps eliminate persistent dampness on garage walls and ceilings. This prevention removes favorable conditions for mold and mildew growth, which helps improve indoor air quality and reduces health risks.
Prevent surface coating damage: Garage waterproofing helps stop paint peeling, epoxy blistering, and efflorescence caused by moisture vapor transmission. This prevention increases coating adhesion by 30-40% and helps maintain floor and wall finishes under loads of 1,500-3,000 lbs (680-1,360 kg).
Protect vehicles and stored materials: Waterproofing helps prevent rust formation on vehicles and corrosion on tools and equipment. This protection reduces damage to stored materials such as wood, cartons, and electrical items, which helps lower maintenance and replacement costs.
Increase property and garage value: A properly waterproofed garage helps maintain a clean, dry, and usable space. This condition increases overall property value, improves resale appeal, and helps buyers trust the long-term performance of the garage structure.

What are the 4 Garage Waterproofing Membranes?

Garage waterproofing membranes are impervious layers installed on the substrate to prevent water penetration. There are 4 main types of garage waterproofing membranes you can use, such as polyurethane, EPOXY, acrylic, and cementitious

Polyurethane waterproofing: Polyurethane waterproofing membranes are the most commonly used garage waterproofing membranes. It is best for both vehicle parking and workshop garages. Polyurethane waterproofing forms a seamless and elastic layer, and it accommodates structural movement and minor cracks up to 1.5 mm (0.06 in). This membrane resists water, oil, fuel, and abrasion, making it highly durable under daily vehicle traffic.
Epoxy waterproofing: EPOXY is the second most used garage waterproofing membrane. EPOXY creates a seamless, hard, impermeable layer, and it prevents water, oil, and chemical absorption into the concrete. Epoxy also has higher scratch resistance and slip resistance. Hence, these are mostly used on commercial garages and many types of parking as well.
Acrylic waterproofing: Acrylic waterproofing membranes are mainly used for exposed garage roofs and external walls. Acrylic waterproofing forms a UV-resistant and flexible coating, and it protects the surface from rainwater penetration and surface cracking. This system works best in areas with direct sunlight and light foot traffic.
Cementitious waterproofing: Cementitious waterproofing membranes are ideal for concrete and masonry garages. Cementitious waterproofing forms a rigid waterproofing barrier, and it stops the water from seeping into the substrate. This system is mostly used for parking garages with light vehicle movement and low impact loads. You should not use cementitious waterproofing for workshop garages because the rigid layer can crack or debond due to sudden point loads, vibrations, and tool impacts on the garage floor.

How to Waterproof a Garage?

To waterproof a garage, you should follow these 8 steps recommended by the Aqviz experts.

Prepare the Surface by cleaning the floor and repairing cracks and holes.
Etch the concrete using a concrete etching solution, and then rinse the floor thoroughly and dry off.
Use a paint roller or brush to apply a concrete primer compatible with your waterproofing membrane.
Seal the concrete using a high-quality concrete sealer, apply the first coat using a roller or a sprayer, and let it dry.
Apply a waterproofing membrane in areas that tend to flood and have high moisture levels.
Apply the second coat of sealer and let it dry.
Let the floor dry, and after curing, inspect the floor and do final touch-ups.
Protect the waterproof garage floor from damage.

Detailed Guide: How to Waterproof a Garage?

Garage Waterproofing steps — These are the 7 steps of garage waterproofing

What Garage Floors Should You Waterproof?

You should waterproof concrete, stone, and basement garage floors to prevent water leakage through the substrate.

Concrete garage floors: You should waterproof concrete garage floors to prevent water from leaking through the concrete layer. Concrete is a porous material. Seepage can occur through the tiny spaces in the concrete layer when it is saturated with water over time. Hence, you should seal the concrete floors to prevent the waterleaking.
Stone garage floors: You should waterproof the stone garage floors to prevent water from leaking because they have tiny gaps and holes between the stones. Stones are porous materials. Small gaps, cracks, and holes allow water and moisture to seep in when saturated with water.
Basement garage floors: You should waterproof the basement garage floors to prevent waterproofing through the cracks and cove joints. The basement can be porous depending on the material it is made out of. When the basement is saturated with water, it can seep through the cracks and the cove joints.

Is Epoxy Good for a Garage Floor?

Yes, Epoxy is extremely good for garage floor waterproofing. Epoxy is a water-resistant material that helps to prevent water from leaking into the garage. Epoxy is an abrasive-resistant material; hence, it helps increase friction between the tyres and the floor, preventing slipping on the garage floor.

Epoxy does not react with chemicals; therefore, it does not react with oil and grease, preventing vehicles from slipping. Epoxy is seamless, making the garage floor easy to clean and slip-resistant. UV resistance of epoxy prevents color fading and yellowing, and protects the bonding between epoxy paint layers in the garage floor. The durability of epoxy paint can resist damage from heavy vehicles and prevent the need for continuous repairs and maintenance of the garage floor.

Epoxy garage floor — Applying EPOXY on the garage floor

What Garage Door Types Should You Waterproof?

You should waterproof these 4 types of garage doors: wood garage doors, metal garage doors, aluminum garage doors, and roller garage doors.

Wood garage door waterproofing: You should waterproof wood garage doors to prevent 7 sever water problems, such as swelling, rotting, warping, decaying, pest infestation, and paint peeling. You can use wood sealants, varnish, waterproofing membrane, caulking, weatherstripping, and door sweep to waterproof the wood garage doors. Wood sealants help to repel water and protect the wood from moisture damage, preserve natural beauty, are easy to maintain, provide a finished look, and enhance the durability of the garage doors
Metal garage door waterproofing: You should waterproof metal garage doors to prevent rusting, corrosion, paint peeling, stains, deterioration, and weakened structural integrity . You can follow some steps to maintain the metal doors because they typically come pre-painted with a weather-resistant finish and don’t have many direct waterproofing methods. You can inspect and clean, touch up paints, lubrications, weatherstripping, door sweep, and caulking.
Aluminium garage door waterproofing: Aluminium garage doors are generally weather-resistant; therefore, no direct waterproofing methods are available. But you can clean and inspect regularly, including caulking, lubrications, touch-up paints, weatherstripping, and door sweeps.
Garage roller door waterproofing: Garage roller doors are generally pre-finished and weather-resistant. Hence, you can clean and inspect the doors using lubricants, touch-up paints, and weatherstripping to improve the waterproofing ability of glass roller doors.

Garage door types — 4 different types of garage doors

How to Prevent Water from Coming Under the Garage Door?

These 4 methods help to prevent water from coming under the garage door during the rainy season as well as flooding.

Install a garage door water barrier: The garage door water barrier helps to prevent rainwater from coming under the door. The garage door water barrier is a rubber stripe that can seal the garage floor and door bottom.
Install a Door weatherstripping: Door weatherstripping can prevent the entrance of wind-driven rainwater, splashing water from puddles, and snowmelt by creating a tight seal and blocking water entering points. Weatherstripping is made out of rubber, felt, or vinyl. These materials compress against the garage door and create a tight seal under the bottom level of the door.
Adjust the garage door: Adjusting the garage door will prevent water from leaks, cracks, and gaps due to worn-out door materials, rusting, and deterioration. It will avoid entering rainwater and wind-driven rainwater.
Use Sandbags: Sandbags can absorb and stop the water while reducing the flow rate and preventing water from entering the garage. Sandbags are a temporary solution that can be used to prevent the entry of floods and rainwater.

Prevent garage door water leaking — These are the 4 ways of water leaking under the garage door

Are Waterproof Garage Wall Panels Worth It?

Waterproof garage wall panels are needed to prevent water from leaking into the garage. Waterproof garage wall panels help prevent moisture through spills and leaks, provide chemical resistance to protect the walls and maintain their appearance, are easy to clean, prevent mold and mildew, are durable, and withstand bumps and scrapes.

These are the 5 different waterproof garage wall panels.

PVC Wall panels
Glass-reinforced plastic (GRP)
Metal wall panel
Wood composite panels
Epoxy wall coatings

What Can You Use to Waterproof a Garage Roof?

You should waterproof the roof on both metal and concrete garage roofs using the materials.

Metal garage roof waterproofing: You can use elastomeric roof coating, acrylic coating, silicone coating, PU, liquid rubber, and metal roof sealant to waterproof a metal roof. Waterproofing a metal roof helps to extend the roof’s life span, reduce heat transfer, minimize heat loss, reduce noise, and prevent leaks and water damage.
Concrete garage roof waterproofing: You can use liquid rubber coating, polyurethane, or sheet membrane waterproofing materials like PVC or EPDM. Waterproofing a concrete garage roof helps prevent leaks and cracks, extends the roof’s lifespan, reduces repair costs, and improves energy efficiency.

Is Garage Floor Paint Waterproof?

Not all garage floor paints are waterproof. But it has a specific water-resistant capability. Garage floor paints such as acrylic, concrete sealer, and latex paints can be damaged due to abrasion. Hence, these are not suitable as a waterproofing layer in the garage.

Is Garage Wall Paint Waterproof?

No regular garage wall paints are not waterproof, even though they provide water resistance and durability. Water can be penetrated due to its porous nature and limited durability. Hence, these are not suitable as a waterproofing layer in the garage.

What are the 5 Different Ways to Protect Garage Waterproofing?

You should follow the 5 ways to protect the garage’s waterproofing layer.

Install garage door threshold sealing: The garage door threshold seal helps to prevent water from seeping under the door, which dampens the garage floor.
Regular maintenance: Regular maintenance of the garage will allow for proper ventilation and reduce moisture build-up.
Seal the cracks: Sealing cracks will reduce the entrance of the rain to the garage floor and dampen it.
Mange drainage: Managing drains will prevent water from pooling around the garage floor.
Park carefully: Parking vehicles carefully without rough driving and parking too close to the walls can prevent the waterproofing system of the garage.

What are the 5 Ways to Damage a Garage Waterproofing?

Garage waterproofing can be damaged due to poor installation and maintenance of the drainage system, using harsh chemicals, improper storage of heavy objects, DIY repairs, and poor ventilation.

Poor installation and maintenance of the drainage system: The garage waterproofing layer can be damaged due to poor installation, such as improper grading, poor quality, low-quality materials, and inappropriate applications. When the waterproofing layer is improperly maintained, gutters and downspouts can be blocked, and drainage systems can be damaged. These cause damage to the waterproofing layer on the garage floor.
Use of harsh chemicals: Using harsh chemicals such as solvents, degreasers, and cleaners can break down the waterproofing membrane and reduce its effectiveness, causing cracks, peeling, and water leakage.
Improper storage: Improper storage of heavy objects and placing objects against walls can stress floors and walls, damaging the waterproofing membrane.
DIY repairs on complex issues: DIY repairs on complex issues without acknowledging it will worsen the problem. Also, improper sealants and wrong repair methods can damage the waterproofing system.
Poor ventilation: Poor ventilation will increase the moisture built up, causing condensation in garage walls and floors, and damaging the waterproofing system.