---
product_id: 51550815
title: "Ronseal Knot Block Wood Primer and Undercoat White 750ml"
brand: "ronseal"
price: "9354 kr"
currency: ISK
in_stock: true
reviews_count: 10
category: "Ronseal"
url: https://www.desertcart.is/products/51550815-ronseal-knot-block-wood-primer-and-undercoat-white-750ml
store_origin: IS
region: Iceland
---

# Ready to paint over in 4 hours 12m² coverage per litre Blocks knots & imperfections Ronseal Knot Block Wood Primer and Undercoat White 750ml

**Brand:** ronseal
**Price:** 9354 kr
**Availability:** ✅ In Stock

## Summary

> 🖌️ Seal the deal with a flawless base – because your wood deserves the best!

## Quick Answers

- **What is this?** Ronseal Knot Block Wood Primer and Undercoat White 750ml by ronseal
- **How much does it cost?** 9354 kr with free shipping
- **Is it available?** Yes, in stock and ready to ship
- **Where can I buy it?** [www.desertcart.is](https://www.desertcart.is/products/51550815-ronseal-knot-block-wood-primer-and-undercoat-white-750ml)

## Best For

- ronseal enthusiasts

## Why This Product

- Trusted ronseal brand quality
- Free international shipping included
- Worldwide delivery with tracking
- 15-day hassle-free returns

## Key Features

- • **Safe & Ready:** Non-flammable formula, perfect for both amateur and professional use indoors
- • **Matte White Base:** Provides a smooth, neutral undercoat that enhances topcoat vibrancy
- • **Knot & Stain Blocker:** Effectively seals knots and wood imperfections for a pristine base
- • **Flawless Finish, Fast:** Dries quickly so you can move on with your project in just 4 hours
- • **Maximum Coverage Efficiency:** Covers up to 12m² per litre, saving time and materials

## Overview

Ronseal Knot Block Wood Primer and Undercoat White 750ml is a high-performance, non-flammable primer designed for bare and previously painted wood. Offering excellent coverage of 12m² per litre and a fast drying time of 4 hours, it effectively blocks knots and imperfections, creating a smooth matte white base ideal for professional or DIY projects.

## Description

Shop Ronseal Knot Block Wood Primer and Undercoat White 750ml. Free delivery on eligible orders of £20 or more.

Review: Highly recommend - Why did you choose this product over others?: Fantastic product at great price. I used 2 coats on a large door frame made of bare wood. It covered any knots and imperfections well. Painting with a gloss afterwards was super easy. Coverage: Great Dries quickly: Yes Paint quality: Excellent Effectiveness: Excellent
Review: Good value for money - Good value for money

## Features

- Suitable for use on bare and previously painted wood
- Included components: Tin
- Ready to paint over in 4 hours

## Technical Specifications

| Specification | Value |
|---------------|-------|
| ASIN | B00L250GZG |
| Batteries Required? | No |
| Batteries included? | No |
| Best Sellers Rank | 15,260 in DIY & Tools ( See Top 100 in DIY & Tools ) 32 in Primer |
| Colour | White |
| Coverage | 12m2 per litre |
| Customer Reviews | 4.4 4.4 out of 5 stars (846) |
| Date First Available | 17 Jun. 2014 |
| Finish | Matte |
| Included Components | Tin |
| Item Package Quantity | 1 |
| Item Weight | 1.01 kg |
| Item model number | 36481 |
| Manufacturer | Sherwin-Williams |
| Material | wood |
| Measurement System | Metric |
| Number of Pieces | 1 |
| Part Number | 36481 |
| Product Dimensions | 9.9 x 9.9 x 11.9 cm; 1.01 kg |
| Size | 750 ml (Pack of 1) |
| Special Features | Non Flammable |
| Style | Single |
| Usage | Inside;Amateur;Professional |
| Volume | 0.75 Litres |

## Product Details

- **Brand:** Ronseal
- **Colour:** White
- **Finish type:** Matte
- **Item volume:** 750 Millilitres
- **Paint type:** Oil
- **Size:** 750 ml (Pack of 1)
- **Special feature:** Non Flammable
- **Specific uses for product:** Inside;Amateur;Professional
- **Surface recommendation:** Wood
- **Unit count:** 750.0 millilitre

## Images

![Ronseal Knot Block Wood Primer and Undercoat White 750ml - Image 1](https://m.media-amazon.com/images/I/31+5Pmh2F0L.jpg)
![Ronseal Knot Block Wood Primer and Undercoat White 750ml - Image 2](https://m.media-amazon.com/images/I/51O6KGrrguL.jpg)
![Ronseal Knot Block Wood Primer and Undercoat White 750ml - Image 3](https://m.media-amazon.com/images/I/51s6KCJrjzL.jpg)
![Ronseal Knot Block Wood Primer and Undercoat White 750ml - Image 4](https://m.media-amazon.com/images/I/91amOXQBDIL.jpg)

## Questions & Answers

**Q: Upcycling a chest of drawers - can this be used directly on to drawers as they are now or would i need to sand it all down first?**
A: Hi, It would depend on what was originally on the drawers, example if it was a wax or an oil this would need to be completely removed as would cause adhesion problems and could lift and peel. If it is a paint or varnish, you will need to remove anything unsound (flaky or cracked).  In all instances sanding would be needed to provide a key, but not necessarily to remove all of the previous finish unless it is one of the aforementioned products outlined above in the first paragraph. If the wood is bare, we would still recommend a light sand to provide a key.

**Q: Using knot block will timber take wood stain**
A: After using the knot block it leaves the wood with a white finish

**Q: Upcycling a chest of drawers - can this be used directly on to drawers as they are now or would i need to sand it all down first?**
A: It's always best to sand down any wood before painting, use fine sandpaper, any loose bits of flake may take more effort,  it will make the surface a lot easier for the new paint to bond to, a quick wipe down and away you go.

**Q: Ronseal Knot block - is this for internal use or external or both?**
A: Good question. The description given does not specify for outside use.
However, remembering it is an undercoat water based paint I would guess it could be used outdoors.
Nevertheless, if using outside the top coat accordingly would need to be "appropriate " . My only experience is using this paint internally. Customer care enquiry number for Ronseal is  0114 2409469 may give you a more definitive answer.

## Customer Reviews

### ⭐⭐⭐⭐⭐ Highly recommend
*by E***S on 21 June 2025*

Why did you choose this product over others?: Fantastic product at great price. I used 2 coats on a large door frame made of bare wood. It covered any knots and imperfections well. Painting with a gloss afterwards was super easy. Coverage: Great Dries quickly: Yes Paint quality: Excellent Effectiveness: Excellent

### ⭐⭐⭐⭐⭐ Good value for money
*by D***K on 14 January 2026*

Good value for money

### ⭐⭐⭐⭐ Time will tell if it works!
*by B***2 on 12 July 2020*

I bought this to cover knots that were seeping through the paint inside our summerhouse. Despite two coats of this and several coats of white paint they are still visible, though mainly textured shadows, not the yellowy sap colour as it was before. The paint smells very strongly so you want as much ventilation as possible. I found it to be quite thin and runny compared to other primers so you need to be careful to protect floors and other surfaces.

## Frequently Bought Together

- Ronseal Knot Block Wood Primer and Undercoat White 750ml
- Harris Essentials Walls & Ceilings Paint Brush Set | Pack of 5 | 0.5", 1", 1.5", 2", Grey
- Everbuild Multipurpose Wood Filler – Suitable for Indoor and Outdoor Use – Sandable – Light Stainable – 250ml

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*Product available on Desertcart Iceland*
*Store origin: IS*
*Last updated: 2026-01-23*