A Simple Guide to Painting Flush Doors to Get a Great Finish

Painting internal doors, especially flush internal doors may seem like an easy and straight forward job, however to get the very best finish possible there are a few tips and tricks to be aware of.

With this in mind, in this project we focus on how to correctly paint a flush internal door, read on to find out how.

What is a Flush Door?

A flush door is a door without any additions to it, such as the rails and braces you might find on a ledge and brace door or similar.

There are no panels or glazing panes, just a straight forward flat faced door.

In terms of their construction, they are normally made using a 2×1 inch rectangular timber frame, which is then filled with a honeycomb-type cardboard filling. The open front and back sides are then covered with 2mm ply-board or similar.

To ensure you are able to fit a lock and handles, a lock block is also fitted around the centre of the door and the side it’s fitted to is then indicated on the top of the door with a stamp.

Painting a flush door, although they are the most basic of doors, is unexpectedly quite a tricky job, as it’s not possible to stop painting either of the sides until you are finished.

If you do stop for more than a minute or two, the edge of the paint hardens and this can show through the painted finish as a ridge in the paintwork.

Generally, flush doors are the cheapest of all the different door types and as they are not solid and made from rather cheap materials, they also aren’t the strongest and can easily damage.

What Type of Paint to use on a Flush Internal Door?

Generally, the type of paint that you decide to use to paint your flush door is entirely up to you, however there are a few general points to be aware of when choosing paint.

In general, water-based satin or matt finish paints produce some of the best finishes as they produce a very subtle sheen that both highlights the smooth, sleek characteristics of such a door and also provides an easy to wipe surface, making such paints ideal for hight traffic areas.

Another great choice is an oil-based paint. These types of paints are generally much more hardwearing than their water-based siblings and due to this, are again ideal for high traffic areas, however they do take longer to cure and generally have quite a strong odour.

To get the very best finish possible, it’s also essential to use a good quality primer first before your chosen top coat. This will produce a good, solid base for any finishing coats and ensure a top quality finish.

One final important point to note is that when selecting paints (primers and top coats), ensure that each type matches e.g. water-based primer and water-based top coat or oil-based primer and oil-based top coat.

Mixing different paint-types generally does not work as they can react and sometimes repel each other, ruining the overall finish.

Advantages and Disadvantages of Flush Doors

As with all things, there are both advantages and disadvantages to flush doors, so if you are in the market for new doors for your home, it’s essential that you are aware of some of the most significant ones, these are as follows:

Advantages of Flush Doors

• aesthetic appeal: Their simple, smooth and flat finish complements contemporary and minimalist interiors, allowing them to blend seamlessly with pretty much all modern decor.
• cost-effective: They are typically more affordable than panel doors, especially when constructed with hollow-core materials. This makes ideal for budget-conscious projects.
• easy maintenance: The smooth surface of flush doors makes them easy to clean, requiring only a simple wipe-down to remove dust and dirt. Their smooth, flat features also allow for easier re-paints to spruce them up every once in a while.

Disadvantages of Flush Doors

• lack of detail and character: While the minimalist design is ideal for modern interiors, it may not suit more traditional or ornate settings where decorative elements are often a feature.
• less durable: Hollow-core flush doors are lighter and more affordable, but they are also more prone to damage such as dents or warping, especially in high-traffic areas or locations where the door may be subject to rough use.
• limited sound insulation: While solid-core flush doors can provide some reasonable levels of soundproofing, hollow-core versions may allow much more noise to pass through, which can be a great disadvantage in spaces where noise control is important, such as a bed room.

Tools and Equipment Needed for Painting Flush Doors

In order to successfully paint an internal flush door, you will need the following tools and products:

• Selection of screwdrivers or drill/driver
• Dust sheets/old sheets
• Vaseline
• Low-tack masking tape
• Old newspaper
• Chosen paint
• Good quality 2-inch paint brush or roller with quality sleeve
• Sandpaper
• Vacuum
• Door wedges
• Clean rag
• White Spirit

How to Paint a Flush Door

Now that we have looked at exactly what type of door a flush door is, what type of paint to use and what some of the advantages and disadvantages of such a door are, it’s now time to look at exactly how to paint one correctly.

So that both sides of the door can be painted at the same time, we are going to paint it in situ.

Step 1 – Prepare Working Area

The very first job is to prepare the work area. Start by vacuuming the floor and walls around the door to remove any dust, spiders webs etc., to save getting them stuck in the wet paint on the brush.

Also, pull a fairly large dust sheet under the door and right up to the wall to protect any surrounding areas.

Finally, using some low-tack masking tape, tape newspaper to the wall surrounding the architrave, if you are painting this also. If not, you can tape the paper right to the edge of the architrave.

Step 2 – Prepare the Door

Next, prepare the door correctly. Start by sanding the whole door and architrave if you are painting this also down using some medium grit sand paper. Remove any existing loose paint and then feather the edges in so they don’t stand out once painted again. If the door is in bad condition, consider stripping it with paint stripper.

Once sanded, fully vacuum the whole area thoroughly to remove every trace of dust and then wipe over with a damp white spirit-soaked rag to remove any final traces of dust and any grease.

Finally, use a screwdriver to remove the door handles, locks etc. and then smear a little Vaseline on any exposed metal e.g., hinges. This will allow any paint to be easily wiped off.

Step 3 – Apply Primer

With the door prepared, it’s now time to start painting the first coat – the primer coat.

The order in which the door should be painted can be seen in the image below and to ensure full and even coverage, it should be painted this way!

Just to confirm, the order in which you should paint your door is as follows:

• Step 1 – Paint top timber: Paint to the frame timber at the very top of the door
• Step 2 – Paint left side: Paint the frame timber at the hinge side of the door
• Step 3 – Paint lock side: Paint the frame timber at the lock side
• Steps 4-11 – Paint front of door: Divide the front face of the door into 6 or 8 even areas and, starting at the top, paint each one in turn, working your way down to the base
• Step 12 – Repeat for the other side: Repeat steps 4-11 on the opposing face of the door to complete

To paint the door you can use either a good quality paint brush or paint roller and quality sheath.

Do not be tempted to opt for cheap and inferior products. Cheap paint brushes will leave lines and lose their bristles quickly and cheap roller sleeves will leave lines and stipples marks.

Once fully painted, leave the door to dry fully for 24 hours. Also ensure that everyone in the house knows it’s wet!

Step 4 – Apply Top Coats

Once the primer coat has fully dried for around 24 hours, you can then apply the final top finishing coat of paint.

Using the same approach as outlined above, apply the top coat, working your way through all steps, from step 1 down to step 12.

With the first coat applied, again, leave for around 24 hours to fully dry and then give it a very light sand over if any brush marks are present, wipe over with a damp rag and then apply a second, finishing coat.

Once the final coat has cured for 24 hours of so, you are then don, great work!

Step 5 – Clean up

the final remaining job to do is clean up. Remove any masking tape carefully, making sure you don’t pull off or damage any paint or wall paper when you pull it off, remove the chocks holding the door and then fold up any dust sheets.

Although a seeming simply job, painting a flush door can be a little tricky, but as long as you follow the steps outlined above to the letter, then you are sure to get a great, professional finish!