Coo-Var Patent Knotting | Shellac Based Knot Sealer

• Surface Prep: Ensure wood is clean, dry, and free of loose fibres or old flaking finishes.
• Application: Stir product gently if needed. Brush a thin layer onto knots/resin-rich areas.
• Drying/Curing: Allow recommended drying time (check datasheet) before applying paint or varnish.
• Maintenance: Once sealed, proceed with primer or direct painting as per your project’s needs.
• Pro Tip: For highly resinous knots, apply multiple thin coats to fully lock out stains.

Need a step-by-step guide? Our experts are here—chat live now!

Fast, Reliable & Fully Tracked UK Delivery

Every order is dispatched from our warehouse using a fully tracked DX or FedEx service, so you always know when your paint will arrive.

Delivery Options

• FREE Standard Delivery (orders over £75) Arrives in 2–3 working days
• Standard Delivery – £7.95 Arrives in 2–3 working days
• Express Delivery – £13.95 Next working day delivery when you order before 12:00 noon (Mon–Thu)
• Spending £75+? Select Express Upgrade at checkout and only pay the difference

Dispatch & Delivery Times (What Happens After You Order)

• Express delivery (order before 12:00 Mon–Thu) Dispatched same day, delivered next working day
• Standard delivery (Mon–Wed orders) Dispatched next working day, delivered 2–3 working days later
• Orders placed Thursday (standard delivery) Dispatched Friday for Monday delivery
• We do not dispatch or deliver on weekends or UK bank holidays

What to Expect on Delivery

Please provide a contact telephone number at checkout. This allows the courier to share tracking updates or contact you if there are any delivery issues.

Most orders require a signature on delivery. If you may not be available during the day, we recommend delivery to a workplace, business address, or another location where someone can sign.

Outside the UK Mainland?

Delivery prices shown apply to UK Mainland only.

For the Highlands, Islands, Northern Ireland, or non-mainland addresses, please contact us for a quick personalised quote via live chat, by calling 01482 222 421, or emailing info@specialistpaintsonline.co.uk.

Bottom Line

Order today, get fast and reliable delivery, track every step, and get painting without delays.

Free Delivery on Orders Over £75: Pick up everything you need in one go to qualify

• Coo-Var Primers & Undercoats: Ideal for a fully prepped paint job
• Specialist Wood Care: Protect and enhance your wood’s natural grain after knotting
• Application Tools: Brushes, paint trays, and extension poles

Want everything in one basket? Chat with us for recommended extras!

Coo-Var Patent Knotting seals knots and resinous spots in seconds, ensuring every timber project dries blemish free first time. Backed by over 100 years of British paint innovation, it’s arguably the most reliable knot sealer money can buy. Its rapid dry, high coverage shellac formula lets you prime the same day, something cheaper alternatives simply can’t match.

Key Benefits 

• Knot Bleed Blocked – Seals sap instantly so you avoid discolouration, rework and warranty callbacks.
• Smooth Prep Workflow – One quick coat levels fibres and cuts sanding time, boosting productivity on site or in the shed.
• Finish Stays Perfect – Keeps top coat colour true for years, protecting brand reputation and homeowner pride.
• DIY & Trade Fast-Track – Touch dry in minutes, ready for primer the same day, freeing you to move on and earn more.
• Pound-Wise Economy – High coverage per litre stretches budgets and reduces waste across jobs large and small.

DIY Friendly, Brush it on in seconds, prime the same day and with next-day UK delivery, you’ll enjoy knot-free timber tomorrow; add to basket today and feel the difference immediately.

• Finish / Texture:Base: Shellac solution in alcohol
• Available Colours: Translucent Brown
• Pack Sizes: 0.25 L, 0.5 L, 1 L, 2.5 L
• Coverage: Up to 13 m²/L @ 75 µm WFT
• Drying Times @ 20 °C: Touch dry 10 min; hard dry 3 h; full hardness 2–3 days
• Re-coat Interval: Minimum 6 h @ 20 °C
• Minimum Application Temp.: 5 °C
• VOC Content: 581 g/L
• Flash Point: 12 °C (closed cup)
• Application Method: Brush (clean with Thinners 6)
• Surface Suitability: Knotted or resinous softwood & hardwood, interior & exterior, prior to primer/paint
• Volume Solids: 27 %
• Wet Film Thickness (WFT): 75 µm
• Dry Film Thickness (DFT): 20 µm

Need specifics on drying times or coverage? Chat with our experts now and seal your knot!

Technical Data Sheet

Safety Data Sheet

1. What is Coo-Var Patent Knotting used for?

Coo-Var Patent Knotting is a shellac-based solution designed to seal knots and resinous areas in wood. It prevents discolouration and staining that can bleed through paint or varnish.

2. Can I use this product on both interior and exterior wood?

Yes, this knot sealer is suitable for both interior and exterior projects. It forms a weather-resistant barrier, keeping knots sealed against moisture and the elements.

3. How do I apply the knotting solution?

Simply brush a thin, even coat onto the knots and surrounding areas. Ensure the wood surface is clean and dry before application. For heavily resinous knots, multiple thin coats may be required.

4. Does it affect the appearance of the wood?

The shellac-based solution dries to a translucent finish. It blends with most wood surfaces and is easily covered by paint or varnish without affecting the final look.

5. Can I paint or varnish over Coo-Var Patent Knotting?

Absolutely. Once the knotting solution is dry, you can apply your chosen paint, varnish, or stain, confident that knots won’t bleed through and spoil the finish.

6. Is there any special ventilation or safety requirement?

Use this product in a well-ventilated area, and follow the guidance on the product datasheet for handling instructions. It’s shellac-based, so standard precautions for solvent-containing products apply.

7. How can I ensure the best results?

Focus on covering all knotted or resinous areas thoroughly. Allow each coat to dry before applying any additional layers or topcoats. For tailored advice on your specific wood type or project, get in touch with our experts.

Need help sealing knots or preparing wood surfaces?

For personalised recommendations or further guidance, contact our experts now via live chat—we’re here to help you achieve a flawless, knot-free finish!