7 Best Undercoat Paints Of 2021 In UK – Review & Buying Guide

by Nicole Miles | Last Updated: 07/08/2021

Painting is not as simple as picking up color, and then you are good to go. For the top paint coat to look beautiful and smooth, the undercoat must be applied first. Wood, metal, and concrete surfaces require a primer or an undercoat for the paint to stick well, and therefore, we have created a list of the Best Undercoat Paints of 2021.

Best Undercoat Paints
Best Exterior/Interior Primer Paint Best Exterior/Interior Primer Paint KILZ Premium Stain
  • Colour: White
  • Size: 1 Gallon
  • Manufacturer: Kilz
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Professional Grade Rubberized Undercoating Professional Grade Rubberized Undercoating 3M 03584-6PK
  • Colour: White
  • Size:16oz Cans
  • Manufacturer:3M
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Best Water-Based Primer Best Water-Based Primer Armaly Brands Bulls Eye
  • Colour: White
  • Size: 2.5 ltr
  • Manufacturer: Zinsser
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Rubberized Undercoating Spray Paint Rubberized Undercoating Spray Paint Rust-Oleum Undercoating Spray
  • Colour: Matt Black
  • Size: 400ml
  • Manufacturer: Tor Coatings Ltd
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Rust Preventive Coating gaming laptop under 600 POR-15 Preventive Coating
  • Colour: 473ml
  • Size: 473ml
  • Manufacturer: Absolute Coatings
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gUndercoating Spray Paint Undercoating Spray Paint 3M 08881 Undercoating
  • Colour: WHITE
  • Size: 16oz Cans
  • Manufacturer: 3M
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Undercoat Paint For Wood & Metal Undercoat Paint For Wood & Metal Dulux Professional Undercoat Paint
  • Colour: Pure Brilliant White
  • Size: 2.5L
  • Manufacturer: AkzoNobel
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Undercoat paint reduces the number of coats you need to apply to get the desired color you want. Moreover, it makes the final coat more durable and protects it from cracking. With undercoat paint, you can be absolutely sure that your money won’t go to waste. So before painting, do invest in undercoating.

Best Undercoat Paints of 2021

  1. Best Exterior/Interior Primer Paint – KILZ Premium Stain
  2. Professional Grade Rubberized Undercoating – 3M 03584-6PK
  3. Best Water-Based Primer – Armaly Brands Bulls Eye
  4. Rubberized Undercoating Spray Paint – Rust-Oleum
  5. Rust Preventive Coating – POR-15 45404
  6. Undercoating Spray Paint – 3M 08881
  7. Undercoat Paint For Wood & Metal – Dulux Professional

Best Exterior/Interior Primer Paint

1. KILZ Premium Stain Gallon White

Best Exterior Interior Primer Paint

Kilz is a well-reputed paint brand that has been manufacturing and perfecting their primer range over the years. It has succeeded in creating quality undercoat paints for all kinds of surfaces like the Kilz interior/exterior stain blocking paint. This is a water-based undercoat and applies pretty smoothly on indoor and outdoor wood and walls.

The best thing about this primer is that it contains a very low VOC amount, making it environment friendly. Moreover, the paint has a low odor, which makes the painting process quite smooth. The excessive chemical smell of paints can sometimes make it difficult to work with paint, but that is not the case with this undercoat paint.

It efficiently blocks any stains left from previous coats and smoothly adheres to the wood surface. Since this is a water-based primer, it dries quickly, and you can be ready to apply the final coat just after a wait of 30 minutes. This paint is available in three different sizes, so you can easily get the smallest once for painting your kitchen cabinets.


  • Thick consistency
  • Smooth application
  • Blocks stains efficiently
  • Extensive coverage
  • Dries quickly


  • Requires quick painting

The primer has a nice thick consistency to it, which offers more coverage and prevents the paint from splattering. It comes in white tinted color, but you can also add a different color tint to achieve a rich color for the top paint coat. The KILZ Premium Stain Blocking Interior/Exterior Primer is a high-quality undercoat that applies smoothly and blocks stains with just a single coat.

Professional Grade Rubberized Undercoating

2. 3M 03584-6PK Rubberized Undercoating

Professional Grade Rubberized Undercoating

Vehicle undercarriages need protection from corrosion that is caused due to the presence of moisture and grime, and for this reason, vehicles require rubberized undercoating. The 3M Professional Grade rubberized undercoating comes in the form of a spray and prevents corrosion and removes dust.

The formula used in this spray undercoat paint is such that it does not drip when you are applying the coat. This allows for a clean panting process, and the paint does not go to waste. It acts as a protective covering over the undercarriage and enhances its durability. This is a versatile spray paint that can be used on all vehicles, making it one of the best undercoat paints for 2021.

The best thing about this spray paint is that it reduces the amount of noise that a vehicle creates when it is moving. It forms an even layer when applied on the undercarriage and hides small cracks that may be present due to the old age of the vehicle. This high-quality undercoat spray can surprisingly increase the lifespan of badly rusted undercarriages.


  • Prevents rust build-up
  • Reduces noise vehicle noise
  • Enhances undercarriage durability
  • Easy application
  • No paint drippings


  • Bad odor

The thick spray coating allows it to stay longer and create a protective barrier over the vehicle’s underside. This spray undercoat paint is quite affordable, which makes it worth buying. The 3M Professional Grade rubberized undercoating is ideal for vehicle undercarriages as it makes rides pleasant and enhances the underside’s durability.

Best Water-Based Primer

3. Armaly Brands Bulls Eye Stain Killer

Best Water Based Primer

The Armaly Brands Bulls Eye 1 2 3 is another water-based primer that can be used on almost all indoor and outdoor surfaces. You can use it on walls, wood, and plasterboards. This undercoat paint has a pretty easy application process and covers any stains that may be present on the surface.

The formula used in the creation of this paint makes it adhere quickly to walls and concrete. This paint has a very light and vague odor, so you won’t have to deal with the annoying smell of the paint. The smooth texture of the paint makes it easy to apply, and it adheres efficiently to surfaces.

To achieve a rich and dark color for the top paint coat, you can also add tint to the undercoat, and it will make you apply fewer coats for the main finish. It takes about an hour to completely dry, so you can paint patiently without having to worry about it drying too quickly. You don’t need to reapply it as it hides the porous surface on the first coat.


  • Suits all surfaces
  • Adheres quickly
  • Offers thick paint coating
  • Prevents mold
  • Good consistency
  • Easily covers stains


  • Slightly expensive

The protective layer created by this primer prevents the build-up of mold. It creates a safe barrier for the top paint coat so that it can last longer. The Armaly Brands Bulls Eye 1 2 3 is an amazing undercoat paint that adheres quickly and allows for thick protective paint coating.

Read Our Latest Review About:Best Decking Paints

Rubberized Undercoating Spray Paint

4. Rust-Oleum Spray Paint

Rubberized Undercoating Spray Paint

The Rust-Oleum is another rubberized undercoating spray paint that is applied on wheel wells and vehicles underside to prevent them from rust. The spray paint adheres to metal surfaces quite well, and it takes about an hour to dry completely. It comes as a 6 pack can package, and each can contains 15 ounces of paint that can cover a large area of 15 square feet.

It applies smoothly on metal, and the spray covers rust build-up. Driving the vehicle in different environments can allow for moisture to settle at the underside of the vehicle, which leads to corrosion. So it is better to take care of the vehicle and do regular undercoating than to spend a lot of money repairing the damages.

The spray paint forms a neat layer over the metal surface and sticks to it smoothly. You must wait for it to dry before applying a second coat for better results. When the coat is wet, it appears dark brown, but it gradually turns to black when it starts drying up. A lot of people found it to be quite user-friendly, which makes the application process quick.


  • Good coverage
  • Offers even coating
  • Easy to paint
  • Rich color
  • long-lasting


  • Splatters sometimes

The noticeable thing about this undercoat spray paint is that it spreads evenly on the entire surface, so with double coats, you won’t see any faint spots. The Rust-Oleum Rubberized Undercoating spray paint is well appreciated by its users for offering easy application and prevention from rust and moisture. Therefore, you must check it out for keeping your truck or car in good condition.

Rust Preventive Coating

5. POR 15 45404 Rust Preventative Paint

Rust Preventive Coating

POR-15 45404 is a rust preventive undercoat paint that can be used on any metal surface to overcome the damage done to it by the environment. It stops rust from coming back after you apply two coats. The paint coat quickly hardens and forms a protective layer over the metal surface to protect it from corrosion.

It offers extensive coverage, and the paint applies to the rusted surface pretty smoothly. If you want to use it as a spray, then you must get a good respirator and take precautionary measures so that you don’t inhale the chemical toxins. You can also apply it with a paintbrush.

You can say goodbye to the rusty metal as it completely seals the rusty surfaces and protects moisture from getting in. As a result, the metal won’t peel or crack up, making it last longer. Before applying this undercoat paint, you must clean the metal surface properly to make the undercoat adhere perfectly. It would be best if you also covered it with a top coat to prevent it from sunlight.


  • Prevents rust build-up
  • Forms a thick protective layer
  • Resistant to heat
  • No paint peeling or cracking
  • Repels moisture


  • Requires a top coat

The undercoat paint finish is rock solid and does not let oil to collect on the surface. Once it has dried up, it does not let any kind of moisture penetrate through it, which makes it worth considering. The POR-15 45404 rust preventive undercoat paint does a great job of protecting metal surfaces from moisture, so you should definitely invest in it.

Undercoating Spray Paint

6. 3M 08881 Rubberized Undercoating

Undercoating Spray Paint

3M is a popular company that creates products for the automotive industry, and their products are quite affordable. The 3M 08881 is another affordable undercoating spray that can be used to coat the rough and damaged surface of the undercarriages. It takes about half an hour to dry, and then you can put on the second coat to make it thick.

Before applying this spray on a rusty metal surface, the surface must be cleaned and scrubbed so that the spray can be applied on an even surface. The best thing about this undercoating spray is that it does not drip so that you can work smoothly with it. Therefore, you can definitely expect a clean painting process.

One can of the spray provides pretty good coverage, and the paint is highly durable. It won’t peel after some time, unlike most undercoating spray paints, which has a short lifespan. This undercoat paint spray works amazingly well on wheel wells and gives them a brand new glossy look.


  • Highly affordable
  • Offers large coverage
  • Smooth application
  • Durable
  • Dries quickly


  • Require several coats

This is a very versatile undercoating paint spray and can be used on any metal surface that has been damaged by rust. The amazing affordability of the 3M 08881 makes it worth buying as it can protect vehicle undercarriages from abrasion and rust. It can also help in reducing the loud noise created by the undercarriage when driving at high speed. If you are looking for an affordable undercoat spray, then you should consider getting the 3M 08881.

Undercoat Paint For Wood & Metal

7. Dulux Professional Undercoat Paint

Undercoat Paint For Wood & Metal

Dulux is a well-known paint manufacturing company that is aimed at creating long-lasting paints. The Dulux Professional is a high-quality undercoat paint and can be applied to both wood and metal. The paint provides a shiny and glossy finish when applied on wood, and the consistency is so thick that you won’t need a second coat.

It is available in two sizes, so you can opt for either small or large paint that can depend on your project. If you want a strong color finish, you can apply more coats with a time gap of 16 hours so that the paint can harden efficiently. You can apply it on both indoor and outdoor surfaces.

The application process is quite smooth as the paint adheres amazingly to the wood and metal surfaces. Before applying the undercoat, make sure that the wood or metal surface is properly cleaned so that you can have better final results.


  • Hides cracks and stains
  • Perfect for wood and metal
  • Thick consistency
  • Affordable
  • Long-lasting


  • Takes longer to dry

The paint is glossy, and the nice consistency of the paint makes for a shiny paint finish. You can use this undercoat paint for garage doors as it sticks smoothly to metal. It offers amazing durability and effectively hides cracks and stains. The Dulux Professional undercoat paint is affordable and easily sticks to metal and wood surfaces making it worth buying.

Buying Guide

Undercoating paint is significant for metal surfaces, wood, and drywalls as it prepares them for the final coat and seals the top layer. Skipping the undercoating step in a painting process can reduce the durability of the paint. Without an undercoat, the paint starts to peel after some time, or the paint does not stick well to the painting surface.

Undercoating Types

There are many kinds of undercoat paints available for different painting surfaces, so when looking for undercoat paint, you must consider the painting surface. We have explained the different undercoating types below to help you understand which one works better for a given surface.

Rubber Based Undercoating

Rubberized or rubber-based undercoating is usually used for vehicle undercarriages and any other metal surface that has been damaged due to rust buildup. The main ingredient in rubberized undercoating is oil, which repels moisture and other road grime.

If you want to keep your vehicle in good condition and protect the underside from corrosion, you must invest in a good rubberized undercoating paint. It is usually available in a spray can that is easy to apply. Some of the undercoating paint sprays use special paint formulas, which makes them drip-free. So always look for such sprays for a smooth application process.

Water-Based Undercoating

Water-based undercoating paints are applied on drywall and wood surfaces. A water-based primer or undercoat has a very faint odor to it, which makes it pleasant to use. These are quite easy to apply on both wood and drywall and does a perfect job of hiding all the stains and cracks.

One essential aspect of water-based paints is that these take less time to dry as compared to solvent-based paints and have very low VOC content. In terms of application, it adheres smoothly to surfaces and does not create too much mess. If you are working on a small DIY project for your home, you should definitely go for a water-based undercoating paint.

Asphalt-Based Undercoating

Asphalt based undercoating are professional-quality paints that are used on military vehicles due to their amazing quality of rust resistance. It provides high paint durability but is usually quite expensive. These undercoating paints have a thick consistency, which makes them highly suitable for large vehicles that are always on the road.

Things To Consider When Buying Undercoat Paints

When looking to buy an undercoat paint, there are some aspects of undercoat paints you must consider before selecting one. It is essential to know about the surface you are going to be painting on and how much area you are going to cover. Moreover, the consistency of paint and ease of application are also important things to keep in mind for achieving better results.