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How to Use a Paint Primer


Priming walls is an important step of painting that can promote paint adhesion, improve sheen and help cover stains. Learning how to properly prime your surfaces will allow the true colour of your topcoat to shine through. To achieve professional results at home follow this simple guide on how to paint primer on walls and other surfaces.

Shop everything you need to produce a uniform finish at The Paint Shed today. With trade paint and primers from Johnstone’s Trade, Zinsser, Crown Trade and more available, you will find everything you need to get started.

When to Use Paint Primer

Paint primers act as a base coat, creating the foundation for a flawless paint job. You should always use a primer if you need to cover imperfections, conceal stains or neutralise the colour of a surface before painting. It creates a foundation for brilliant colour and a smooth seamless paint application. In most cases we recommend using one coat of primer before two coats of your chosen paint to achieve a professional finish. For porous surfaces (wood/masonry) or to cover dark colours a second coat of primer may be required.

If you are questioning the condition of your wall or surface before painting e.g if it is chalky, stained, powdery or peeling then a primer is required. This also applies to surfaces that have been repaired or patched in the past or if you’re moving from a dark to light colour or from a higher sheen to a lower sheen. In these scenarios, a primer will support a seamless transition. 

There are different categories of primers available at The Paint Shed depending on your needs, e.g drywall primer, wood primer, metal primer and multi-purpose primers. Bonding primers, in particular, are perfect for more difficult, awkward surfaces while sealers are capable of managing stains in a single coat

For more information on the best type of primer for your painting project look to our tips and advice page where we explain when you should use a primer or undercoat.

How to Paint With Primer


Picking Your Primer

For painting interior walls you can use either a water based or oil based primer. An oil based primer is recommended for blocking stains and covering porous surfaces. For covering deep colours you will need a tinted primer. Most primers can be tinted to provide good coverage and at The Paint Shed we can mix any primer to your exact requirements. Be sure to have enough primer to cover your entire surface, if you are not sure how much you will need use our handy paint calculator.

Preparing Your Surface 

Prepare your wall by removing shelves and any hanging hardware (outlet covers, light switch covers etc.) Repair any holes, dents or imperfection with caulk, apply and remove any excess with a putty knife. Allow to dry completely before sanding with fine 220 grit paper, wipe clean with a damp towel and allow to dry before priming. 

Protect Your Surroundings

Remove all furniture and ensure the room is well ventilated before priming. Cover any remaining pieces with a drop cloth to protect against paint splatter. Use painters tape to mask off mouldings, fixtures, trims and the ceiling.

*Before painting we recommend that you dampen your roller or paint brush so that the primer can be evenly absorbed. For water based primers water will be sufficient however for oil based primers a paint thinner or mineral spirit will be required. Squeeze out excess liquid before using your primer. Be sure to safety glasses for this step and when priming your wall.

Cut In and Spot Prime

First, you should apply primer to the corners and edges of your wall before starting on the areas that require extra attention. Cut into corners with a 2-3 inch brushl. Next, spot primer any areas where stains, wood, drywall or plaster are exposed.

Roll on the Primer 

After you have tended to any imperfections move on to the larger spaces of the wall. Use a 9-inch roller for a quick and seamless application. Start by pouring your primer in a paint tray then cover the entire roller with a primer before rolling off any excess on the ridged area of the paint tray.

Paint a vertical strip at the cut in corner, then work around the room applying the primer from top to bottom. Reload the roller when necessary and always overlap areas of wet primer.

If a second coat of primer is required, allow the first coat to fully dry before repeating the process.

Sand Primer

Finish off by lightly sanding your primed wall with a fine-grit sandpaper, this will help smooth your surface for painting. 


How to Use Primer on Different Surfaces

Depending on what you are painting, priming has a few different functions. If you are painting a new or porous material such as wood or plaster you will always need a primer as a base. For shiny surfaces such as metal, plastic or tile the primer will help the paint adhere to the glossy surface.

Priming New Surfaces 

If you’re working with a new surface, be that a re-plastered wall or exterior wall which hasn’t seen a lick of paint before, you’ll want to get a product specifically formulated to help create a strong bond. Some of the most notable would include Crown Trade New Build Acrylic Primer and Crown Trade Stronghold Undercoat White. Follow the same process for priming as detailed above, but aim to paint within 48 hours of priming so the primer can physically and chemically bond to the paint to create an even and smooth coverage.

Priming Metal Surfaces

Priming is a very important step in preparing metal for paint, especially if the surface will be exposed to moisture. Start by cleaning your surface before removing any loose paint and rust with spirits and sanding. Repair any holes or imperfections with a metal putty, wipe the surface clean and begin priming. Apply evenly on a dry and non-windy day if working outdoors. Priming immediately after cleaning is imperative to prevent a build-up of dust and flash rust. 

We have over 50 types of metal primer in stock. We would recommend you look at some of the differences in products before deciding on one. For example, Zinsser Allcoat Exterior Satin can be used on most exterior metals without having to sand, while Coo-Var Red Oxide Metal Primer is a good primer for ferrous metal.

Priming Ceilings

Ceiling paint can crack and peel if not prepared properly. If your ceiling has stains use a roller to prime the surface with a coat of latex paint primer. If it lightly textured opt for a latex drywall primer or a high build option to cover imperfections. Cut the corners and apply as stated above. Allow a few hours to dry before painting. 

More Decorating Tips & Advice

Applying a primer before you paint helps to create a better finish for your topcoat. If you want your paint job to look fresh for longer, priming is a vital step in the painting process. The benefits far outweigh the extra work and priming can actually make painting easier in the long run. Not to mention you can also get the job done with fewer coats when you properly apply a primer, saving you time and money.

Browse our wide range of primers today to perfect your paint job. For more information on priming, painting and decorating look to our tips and advice blog or check out these helpful guides.