How To Paint Internal Doors

Paintbrushes and tools

If the internal doors in your property are to look their best, you’ll need to occasionally apply a coat of finish. This will ensure not only that your doors look fantastic, but that they’re protected against bumps, scrapes, and the build-up of moisture. While these threats are less pressing on the inside of your home than on the outside, the value of the right treatment can’t really be overstated – it’ll ensure that every door in your home is fit for the job!

When it comes to choosing a finish for your internal doors, you’ll have several options available, each with slightly different properties. For best results, you’ll need to not only select the right one but apply it in the right way, too. In this article, we’re going to explore the different treatments available for internal doors.

Finishing Interior Doors: Different Finishes

To begin with, let’s consider some of the finishes available to owners of internal timber doors.


An oil will soak between the fibres of a wooden door, accentuating the grain and helping to achieve that classic timber look. An oil-based finish is slightly more durable than a wax, and thus it’s more suitable for doors and other items of furniture. With that said, it’s easy to work with and repair – minor nicks and scratches can be simply sanded down and re-finished.


A varnish is the strongest type of wood treatment. It will sit on top of the wood, forming an extra-tough, shiny layer of protection against mistreatment. You’ll then be able to maintain the door by simply wiping it down with a damp cloth. Varnishes are typically made from polyurethane, which is the same stuff they use to make kitchen sponges. Opt for a high-quality varnish, and you’ll avoid the possibility of it discolouring over time.


If you’d prefer a splash of colour in your interior (or neutral white) then you can plump instead for a painted finish. Paints have the advantage of coming in any colour you like, and you’ll find white primed doors available, with a coat of primer already applied (we’ll get to that a bit later). This will save you the job of having to apply the primer yourself.

Gloss versus Satin versus Eggshell

The paints used on doors need to be a little more resilient than the ones we use to treat walls and ceilings. You’ll be able to choose between gloss paint, which is the most shiny and dirt-repellent, eggshell, which is the least, and satin, which sits somewhere in the middle. The shinier the paint, the more difficult it will be for dirt and grease to stick to it. Given that your doors are going to be absorbing a lot of fingerprints over the years, we can rule out the matt-effect paints used to paint walls.

What about bathrooms?

Certain places in your home will be more vulnerable to excess humidity than others. These are, most notably, kitchens, bathrooms, and airing cupboards. As such, we would suggest going for something safe and glossy in these areas.

How to Treat Internal Doors

Now that we’ve picked out a finish, let’s take a look at how to use that finish to treat interior wooden doors.


First, you’ll need to prepare both the area and yourself. Lay down protective dust-covers, and make sure you’re wearing something that you don’t mind getting dirty. If you’ve got a dedicated workspace, then so much the better; if you haven’t, then clear one. You’ll need a flat surface, which can be created with the help of a pair of sawhorses.

Mask Away

You’ll need to protect the internal door fittings and glazing. Use masking tape to cover up the glass and unscrew the handles and hinges and set them aside. Lay the door flat across your sawhorses; this will prevent the paint from running after it’s been applied.

Sanding and Cleaning

You want the surface of the timber to be perfectly smooth. Scrub using a damp sponge to lift away any muck, and then sand with fine wet-dry paper. Ensure that the door is thoroughly dried before applying your finish – you don’t want to seal in any moisture. Note that if you’re treating new internal doors, you probably won’t need to bother with this step, as they’ll have been made smooth at factory level.

Applying the Finish

Now it’s time to actually apply your finish. You’re going to use a wide brush to apply a thin layer. Make your strokes as long and even as possible and move with the grain of the door to ensure the smoothest possible coat. Wipe away excess oil or varnish with a suitable cloth. Wait until the first layer is totally dry before applying another, building up steadily until you’ve got the desired effect.

In order to create a seal around the entirety of the door, you’ll need to cover every surface – including the top and bottom edges and the spaces behind hinges and locks. Fail to do this, and moisture will be able to get into the timber. Once it’s got into the spaces between the fibres, it’ll expand and contract in response to changes in ambient temperature and pressure. This will, over time, lead to the entire door changing shape, making draughts more common and causing the door to stick against the frame.

Finishing Up

Before you can get your door back into position, you’ll need to remove any imperfections in the coat of finish. This should be done using an extra-fine finishing pad. If you’re satisfied with the look of the door, you can then hang it. If not, continue applying coats until your door looks immaculate!

Painting Internal Doors

If you’re painting the door rather than oiling or varnishing it, then you might be able to save time by using a roller rather than a brush – that is, if the surface of your door will allow it. Paint in the fine details before moving onto the long strokes. Again, you might need to apply several coats before you get there – and all of the preparation required before applying oil or varnish to a timber door should also be applied to a wooden one.

Can Interior Doors be Different Colours?

There’s a reason that most homeowners opt for a neutral colour across all of their interior doors. Taking this approach lends the building some internal consistency and prevents it from looking like a hodgepodge of rooms from different properties stuck together. You’ll also be able to save money by buying a single large pot of paint rather than several small ones. Having said that, a little bit of variety might be exactly what your interior needs – and personal taste is sure to play a considerable role in your decision.

Can Interior Doors be Spray Painted?

Spraying, in theory, allows for a more even distribution of paint. You’ll have no visible brush-marks, and you’ll be able to get the job done quickly. With that said, you’ll need to take the entire door off its hinges and prop it up somewhere out-of-the-way, where the chance of overspray is limited. Bear in mind that when you’re spraying a lot of the paint will be wasted, as it’ll float away as vapour. Moreover, you’ll need to use a heavy-duty paint-sprayer that’s capable of distributing gloss and semi-gloss paints – a cheap can of aerosol simply won’t cut it!

As such, unless you intend to paint more than half-a-dozen doors simultaneously, a brush (and perhaps a roller) is the best solution.

Pre-finished Internal Doors

If you’d like to avoid work for yourself, you might buy your doors pre-finished. The coat of finish applied at factory level tends to be a cut above that which you might apply at home. It’ll last longer, look better and doesn’t require that you invest in any special tools, or give up a weekend to get your entire house re-finished.

Your choice of finish will be limited, and you’ll eventually need to re-finish your door anyway when the factory finish begins to wear. But if you’re looking for a way to save time and energy, opting for pre-finished internal doors is a great way to proceed.

A compromise between pre-finished and unfinished doors also exists. You might opt for pre-primed doors, which come with a coat of white primer, allowing you to apply any colour you like as a topcoat. This allows you both convenience and flexibility, and it’s worth considering if you’re going to be painting your internal doors.

In Conclusion

By occasionally re-finishing your internal doors, you’ll lend them a new lease of life, and help your interior to look its best. For best results, we recommend setting aside an entire weekend to do the job – as you’ll need to apply several coats to each side of each door, allowing each to dry thoroughly before moving onto the next. Painting during summer is often best, as it’ll allow for the fastest possible drying. Do the job right, and your finish should last for years!