The Best Knotting Solution 2022

Before painting any wood, it’s important that you treat any knots with a knotting solution to avoid any seepage or discolouration of the final finish. Within this article, we list some of the best solutions that are easy to apply and very effective.

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Best Knotting Solution
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If you require a quick answer, the best knotting solution is the Rustins KNOW300, which seals all knots and is easy to apply with a brush. However, if you want to prime and undercoat the wood at the same time, the Ronseal Knot Block is the best alternative that promises a durable finish.

To rate the knotting solutions within this article, we based our recommendations upon testing, research and multiple factors. The factors we considered included their effectiveness, ease of application, compatibility, time to dry and value.

Knotting Solution Comparison

Knotting SolutionTypeSize
Rustins KNOW300Sealer300ml
Ronseal ColronSealer125ml
Ronseal Knot BlockPrimer & Undercoat2,500ml
Liberon PaleSealer125ml
Centurion PatentSealer500ml

Although you could paint wood without treating the knots, after a few years you may begin to see the consequences. This is due to the fact that the seepage from the knots will cause discoloration to the paint.

Below is a list of the best knotting solutions that are easy to apply and effectively seal all knots.

The Best Knotting Solution

1. Rustins White Knotting Solution

Rustins Knotting Solution
By far the most popular and highly rated knotting solution is by the Rustins brand. It’s designed specifically to seal knots in wood and other timber and it can also be used for interior or exterior use.

Other features Rustins KNOW300 include:

  • Pure shellac formulation
  • 300 ml bottle
  • Fast drying
  • Requires two coats
  • Application by brush

Overall, the Rustins knotting solution ticks all the boxes and it does exactly what it sets out to do on the bottle, which is of course to seal knots. It isn’t the cheapest formula but it’s definitely worth paying the extra for. We used this particular formula before painting skirting boards and we have no complaints whatsoever.

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2. Ronseal Colron Knotting Solution

Ronseal CKS125 125ml Colron Knotting Solution
The Ronseal Colron is another popular knotting solution that permanently seals knots and resinous timber. A unique feature of this particular knotting solution is the fact that it comes with an in pack brush. This has the benefit of less mess and no requirement of a paint brush when treating knots with this solution.

Other features of the Ronseal Colron include:

  • Application by the integrated brush
  • Low odour formula
  • Easy to apply and fast drying
  • Prevents discolouration
  • Only suitable for interior wood
  • 125 ml tin

The Colron knotting solution by Ronseal is a great option to consider that’s highly effective and even comes with its own brush. However, unlike the Rustins alternative, it’s only suitable for interior use and also comes in a much smaller bottle, which means it may be expensive to use if you are treating lots of knots.

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3. Ronseal Knot Block Primer and Undercoat

Ronseal RSLKBPU25L Knot Block Primer and Undercoat
Another formula by the Ronseal brand is their Knot Block, which is a wood primer and undercoat solution. According to the brand, it’s everything that you need in a tin and it’s guaranteed to block wood knots.

Other features of the Ronseal Knot Block include:

  • Primer and undercoat
  • Permanently seals wood knots and resins
  • Won’t yellow, crack or peel
  • Touch dry in 30 minutes
  • Helps paint stick and last longer

The Ronseal Knot Block is by far the best knotting solution if you want a base ready to paint onto such as skirting, door frames and architraves. The only drawback is the premium price tag but when you consider that it primes and undercoats, it’s a worthwhile investment that you won’t regret.

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4. Liberon Knotting Pale

Liberon LIBKP125 125 ml Knotting Pale
One of the cheapest knotting solutions on the market that’s actually worth buying is the Liberon Knotting Pale. According to the brand, it’s suitable for all types of wood and it can be painted upon after two hours.

Other features of the Liberon Knotting Pale include:

  • Touch dry in 15 minutes
  • Prevents seepages from knots
  • Pale in colour
  • Suitable for use with clear varnishes
  • 125 ml bottle

Overall, the Liberon Knotting Pale is an excellent all-round option that’s effective and offers great value for the money. Regardless of the type of wood that you treat, you can rest assure that this formula won’t allow any seepage.
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5. Centurion Patent Knotting Sealer

Bottle Patent Knotting
The Centurion Knotting Sealer is another relatively affordable solution that comes in a large 500 ml tin for treating plenty of wood knots. It’s designed to be used prior to priming and undercoating and it can be easily brushed onto the wood with ease.

Other features of the Centurion Knotting Sealer include:

  • Prevents discolouration
  • Fast drying formulation
  • Brush application
  • Interior or exterior use
  • 500 ml bottle

Overall, the Centurion Knotting Sealer is a great option to consider that’s affordable, effective and won’t disappoint.

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How We Tested & Rated

Whilst changing all the door frames, architraves and skirting boards within a recent house renovation, we took the chance to test a number of knotting solutions. This involved brushing the formula onto the knots before painting. We also tested the solutions upon an outdoor wooden seating area and so far it’s certainly stopped any seepages from the knots.

As well as testing, we also based our recommendations upon plenty of research and a number of factors. The factors that we considered included their effectiveness, ease of application, compatibility, time to dry and value.

Knotting Solution


Although you can go ahead and paint onto wooden surfaces straightaway, you may regret it later on. Wood knots can ruin the completed finish of the top coat and cause discolouration. Therefore, to avoid disappointed, it’s crucial that you treat the wood knots before applying a primer or undercoat. All of our recommendations above are suitable for all types of wood and are very easy to apply.

The Author Who Worked On This Article

author dan darimo

Dan Morgan

As a keen DIY’er, gardener and somebody that loves the latest tech, Dan is someone that brings years of experience in multiple trades. Since buying his first house, he has been obsessed with renovating properties and filling it with the latest products. This has led him down the road of testing hundreds of products and creating in-depth “how-to” and informative guides that offer his first-hand experience. Other interests include working on cars, keeping fit through sports or his home gym, caravanning and drinking great coffee.

If you would like to read more about Darimo and the authors, you can visit our about page. This goes into great detail regarding how we test products, create our guides and everything else.

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