Seasonite applied to new wood decking

How to remove mill glaze

What is mill glaze?

Mill Glaze is a phenomenon that produces a shiny surface to new timber through the milling process. The cutters of the planer close the wood pores whilst the natural oils come to the surface of the timber through the machining heat.

As the wood cools these oils produce a glaze on the surface of the wood. This glaze will prevent the penetration of oil or water-based coatings.

Should I treat my new timber?

The guidance from many coatings manufacturers is that newly exposed timber should be left for several months prior to treating it. Owatrol strongly advise against this as this is when the wood is at its most vulnerable to damage due to the moisture transformation.

The inherent moisture expels rapidly and the timber will draw in and release moisture content which will cause warping, cracking or splitting. If you are not intending on removing the mill glaze and then finishing your softwood surfaces we would highly recommend using Seasonite new wood protection.

It is applied in one generous coat including working it into the end grains and helps to protect your new wood whilst it is most vulnerable. The wood can then be cleaned and finished 6-12 months later after which time there should be no mill glaze to remove.

If you have hardwood surfaces please contact us before using Seasonite and never use Seasonite on oak.

How to remove Mill Glaze and open timber pores for optimum penetration

The Owatrol products required for this process are Prepdeck high grade wood stripper and Net-Trol wood cleaner and neutraliser.

prepdeck-packaging-2016nettrol-packaging

Applying Prepdeck to remove mill glaze

  • To reduce mill glaze, add 1 part Prepdeck to 4 parts water.
  • Apply Prepdeck/water solution to the area to be treated with synthetic brush or roller.
  • Allow it to work for 20 minutes.
  • Scrub the area with a stiff nylon brush, deck brush or use a Power Washer at 1000-1500 psi (70-103 bars).
  • Always work in direction of grain.
  • Rinse with copious amounts of fresh water, using the highest pressure from the water source available. You can also use a Power washer at 500-1000 psi (35-70 bars) working in the direction of grain.

Neutralising the wood after using Prepdeck

  • To neutralise the surface, add 1 part Net-Trol to 4 parts water.
  • Apply the Net-Trol/water solution to the area to be treated with a synthetic brush or roller.
  • Allow it to work for 20 minutes.
  • Scrub the area with a stiff nylon brush, deck brush or use a Power Washer at 1000-1500 psi (70-103 bars)
  • Always work in the direction of the grain.
  • Rinse with copious amounts of fresh water, using the highest pressure from the water source available. Alternatively, use a Power washer at 500-1000 psi (35-70 bars) working in the direction of the grain.
  • Leave the wood to dry for a minimum of 48 hours
  • Then apply your new finish.

What next?

Once the mill glaze has been removed you can use your choice of wood finish to protect your wood from damage and keep it looking at its best for years to come.


We hope you found this post on how to remove mill glaze interesting. If you have any other advice or top tips, please feel free to leave them in the comments below. We love hearing from you!

You can also follow us on Twitter, Facebook, Instagram or Pinterest at @OwatrolUK or find us under the hashtag #OwatrolUK

Owatrol Team
About Owatrol Team

Our team are ready and willing to support you with your requirements whether it is protecting your newly laid deck or renovating a luxury yacht, whatever the application Owatrol has the solution you are looking for.

6 thoughts on “How to remove mill glaze

  1. Hi

    I have recently laid an oak decking, I see that your article says not to use seasonite on oak. Should i use prep deck then net-trol to remove the mill glaze before treating?

    Many thanks

    1. Hi Daniel,
      You are correct yes, Seasonite shouldn’t be used on oak. If you are looking to get your wood protected as soon as possible then yes we’d recommend Prepdeck and Net-Trol to remove any mill glaze before using your chosen finish.
      Many thanks,
      The Owatrol Team

  2. Hi ,we are having new decking built with grooved tanalised boards.
    Can you advise me when i should treat them, and will just Aquadeck
    be the one to use.
    many thanks.

    1. Hi there Rod,

      For new wooden decking you have two options:
      Use Seasonite: https://www.owatroldirect.co.uk/product/seasonite/ and allow it to weather naturally for 6 – 12 months before cleaning and applying your chosen finish
      or
      Use Prepdeck: https://www.owatroldirect.co.uk/product/prepdeck/ to remove the millglaze, then use Net-Trol: https://www.owatroldirect.co.uk/product/net-trol/ to neutralise the Prepdeck and then use Aquadecks: https://www.owatroldirect.co.uk/product/aquadecks/ to finish the wood.

      All the best,
      The Owatol Team

  3. Hi, soon I will be installing yellow balau wood decking and have read that Seasonite should be applied. Does the Mill glaze have to be removed first or can you simply coat on top? Also, do I have to coat both sides of the boards?

    1. Hi there Mark,

      Sadly, Seasonite isn’t that effective on hardwood, so we would instead recommend either leaving the wood to naturally weather for 9-12 months, or remove the mill glaze with Prepdeck and Net-Trol as mentioned in the article.

      Please feel free to contact us again should you require any further assistance.

      All the best,
      The Owatrol Team

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