How to treat internal oak doors

This guide answers the common question, "Do internal oak doors need treating?"

Yes, they do.

Before we get cracking, it's a good idea to let you know that you can buy pre-finished internal oak doors, which means that they arrive fully finished with a clear AC lacquer and are ready to hang (you will just need to finish any trimmed edges or cut-outs from fitting hardware). Pre-finished oak doors are our most popular style of door due to the amount of time and effort saved for a relatively marginal price increase on the unfinished version. More information in our pre-finished internal oak doors explained guide.

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As oak is a natural material, it needs treating and ongoing maintenance to keep it looking good and to prevent warping that may occur from moisture absorption. Like a leather sofa, oak likes "nourishment" to prevent the wood from drying out which can lead to shrinkage, warping and splitting. 

Internal oak door treatment options

The main goal with oak door treatment is to create a seal that will protect against moisture, dirt, and finger and hand marks (dirt and grease). The treatment will also make keeping the door clean easier and provide a level of protection against scuffs and wear and tear. Also, treatments will bring out the natural features and graining of the wood.

This guide is specifically related to the oak doors that we stock and you may find differing advice elsewhere. Be sure to check the instructions that arrive with your door as advice does vary slightly between manufacturers, paying particular attention to the finishes that are (or aren't) suitable.

Some doors recommend a stain or microporous wood finish only, whereas others allow for the use of paint, varnish, or lacquer, and some manufacturers recommend a sealer prior to finishing. 

One of the benefits of choosing unfinished oak doors is that you can impart style choices at this stage so that your doors match or complement the rest of your décor and furniture. Pre-finished options are relatively limited. If this is particularly important to your choice of door, please get in touch with us so that we can advise. 

How to treat new internal oak doors

This process assumes that your doors are brand new and have just been delivered. 

  1. Check all your doors for any defects (within 48 hours of delivery)
  2. Prepare a space to treat your doors - this needs to be clean, dust-free and without any source of moisture i.e., fresh plaster.
  3. Lie your door down flat e.g., on a table
  4. Lightly sand all faces and edges with fine sandpaper
  5. Clean and remove any dust
  6. Apply a coat of sealant if recommended
  7. Apply the recommended number of coats of your door treatment (sanding in between coats if recommended)
  8. Allow your door to dry fully in a clean, dry area before hanging

Some treatments require re-application every few years as part of your ongoing door maintenance.

Dos and don'ts of oak door treatment

As stated above, each door manufacturer has individual guidance regarding treatment. However, the following are generally true for all:


  • Use a good quality finish that is suitable for veneered/engineered doors
  • Treat all faces and edges of the door including any trimmed edges or cut-outs
  • Apply the same number of coats to all faces and edges
  • Apply at least 1 coat of finish once the door has been unpackaged
  • Protect any glazing with masking tape (even if there is a protective film)


  • Use a wire wool or sanding material that contains steel or iron
  • Use thin penetrating seals, oils, wax, dyes or hard, brittle finishes
  • Use thinned/mixed paints or stains
  • Mix incompatible products, e.g. paint on one door face and stain on the opposite face


The benefit of unfinished oak doors is that you can apply the finish of your choice (in line with the manufacturers recommendations) which can help tie your doors in with your décor

However, there is a considerable amount of work required upon delivery of your doors before you can install them, and this needs to be up to a required standard in order to satisfy your warranty and adequately protect the door. 

If time is a factor or you do not have the space required to finish your doors in your home, pre-finished internal oak doors may be a better option. Another factor to consider is that the lacquer on pre-finished doors does not need to be touched up every few years and comes with a 10-year finish guarantee. Our range of pre-finished oak doors is always expanding meaning that you will likely find your style of choice available. 


Do oak veneered doors need treating?

Solid and veneered doors need exactly the same treatment.

Can you paint an oak door?

You can, but if you're thinking of painting your doors rather than staining or varnishing them, it would probably be better to opt for primed internal doors. These arrive pre-sealed with a white primer and are ready for painting. 

Can I finish my doors after hanging them?

You can, but finishing the doors on a flat surface will reduce the risk of drips from any stain or varnish, and you can access all edges easily. However, a benefit of hanging your doors first is that you mitigate the risk of damaging the finish while manoeuvring them into place. Either way, add your ironmongery last.

Another point to note is that while varnish can be 'dry' within a few hours, it can take up to a week to achieve full hardness.

Ready to buy?

Click here to view our full range of unfinished oak doors

If you need any advice or guidance, chat with us or contact us and we'll be more than happy to help.