---
product_id: 49444036
title: "Thompsons Damp Seal 750Ml – Permanent Damp Protection For Walls And Ceilings, Easy To Apply, Quick Drying, White Finish, Optimal For Interior Use Before Painting"
brand: "ronseal"
price: "฿3638"
currency: THB
in_stock: true
reviews_count: 8
category: "Ronseal"
url: https://www.desertcart.co.th/products/49444036-thompsons-damp-seal-750ml-permanent-damp-protection-for-walls-ceilings
store_origin: TH
region: Thailand
---

# One-coat white finish Quick 2-3 hour dry time Permanent damp barrier Thompsons Damp Seal 750Ml – Permanent Damp Protection For Walls And Ceilings, Easy To Apply, Quick Drying, White Finish, Optimal For Interior Use Before Painting

**Brand:** ronseal
**Price:** ฿3638
**Availability:** ✅ In Stock

## Summary

> 🛠️ Seal it once, forget damp forever!

## Quick Answers

- **What is this?** Thompsons Damp Seal 750Ml – Permanent Damp Protection For Walls And Ceilings, Easy To Apply, Quick Drying, White Finish, Optimal For Interior Use Before Painting by ronseal
- **How much does it cost?** ฿3638 with free shipping
- **Is it available?** Yes, in stock and ready to ship
- **Where can I buy it?** [www.desertcart.co.th](https://www.desertcart.co.th/products/49444036-thompsons-damp-seal-750ml-permanent-damp-protection-for-walls-ceilings)

## 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

- • **One Coat Wonder:** Full coverage with a single coat saves time and effort
- • **Seal Damp for Good:** Micro-porous formula lets moisture escape while blocking stains permanently
- • **Trusted DIY Essential:** Proven performance with 4.4-star rating and loyal user base
- • **Interior-Ready Protection:** Optimized for walls and ceilings inside your home
- • **Fast-Track Your Renovation:** Dries in just 2-3 hours so you can paint or wallpaper sooner

## Overview

Ronseal Thompsons Damp Seal 750ml is a high-performance, micro-porous interior sealant designed to permanently stop damp and water stains on walls and ceilings. It can be applied directly to damp surfaces, dries quickly within 2-3 hours, and provides full coverage in one coat with a smooth white finish, preparing surfaces perfectly for decoration.

## Description

Product Description Thompsons One Coat Damp Seal is a high performance interior seal developed to form a breathable, obliterating membrane that seals and permanently stops the reappearance of damp, water and other household stains. Suitable for application to both dry and damp walls and ceilings the micro-porous formulation allows trapped moisture to evaporate to prevent paint flaking or wallpaper peeling off. Full coverage can be achieved in just one coat, ensuring the surface is prepared for decoration in as little as 4 hours.Areas of use: Interior walls and ceilings.Finish: smooth White.Application: Brush.Coverage Approx: 5 m2 covered per litre.Required number of coats Approx: 1.Drying time Approx: 2-3 hours.Protection Level: High.The Tompsons RSLTDS750 Damp seal is supplied in 750ml tin.It does what it says on the tinTheir aim at Ronseal is always to provide products that meet exactly your requirements; that is why they spend a lot of time listening to what you have to say. They then take that feedback into their R & D Laboratories, and using the very latest technological advancements, they can then deliver innovative new products and the quality service for your DIY and project needs.This is an ongoing process and, coupled with their no-nonsense advertising and marketing, and their extensive consumer education, these innovative new product developments will continue to help them lead in their product categories, meeting and exceeding your requirements in the future. Box Contains 1 x Thompsons RSLTDS750 Damp Seal 750ml

Review: Effective if used properly - I have used this product previously to help prevent external damp from penetrating too far into a bedroom wall which was on the front elevation of our house. The house was built 1895 and the bricks used to soak up the wet all through the winter and tend to dry out through summer - a continuing cycle. Unfortunately the dampness - while slowly drying out - would permeate through to the inside wall surface, leaving residual marks and causing wall paper to decay and peel. We stripped off all the paper, scraped the wall then applied 2 heavy coats of this product to the wall, waiting a full day between coats. Yes, the coating does smell! It’s spirit-based, it needs to be to prove so effective. We overpainted with anti-condensation paint (2 coats) then standard ‘endurance’ emulsion and have had no further staining for the past 3 years. It is great for what it sets out to do. It is not effective when preparation is not done well, or done at all, but it is excellent for the job we asked it to do.
Review: Good product - Good product that does what it says on the tin. Has sealed a slightly damp wall. Lets hope the rain stops some time soon!

## Features

- Causes serious eye irritation.
- Flammable liquid and vapour.
- May cause an allergic skin reaction.
- May cause drowsiness or dizziness.
- Repeated exposure may cause skin dryness or cracking.
- The Thompsons RSLTDS750 Damp seal is supplied in 750ml tin.
- Micro-porous formulation allows trapped moisture to escape
- Can be applied directly to damp surfaces and permanently stops the reappearance of stains

## Technical Specifications

| Specification | Value |
|---------------|-------|
| ASIN | B001GU89ZG |
| Batteries Required? | No |
| Batteries included? | No |
| Best Sellers Rank | 29,131 in DIY & Tools ( See Top 100 in DIY & Tools ) 475 in Sealers 4,025 in Hand Tools (DIY & Tools) |
| Customer Reviews | 4.4 4.4 out of 5 stars (336) |
| Date First Available | 1 May 2007 |
| Delivery information | We cannot deliver certain products outside mainland UK ( Details ). We will only be able to confirm if this product can be delivered to your chosen address when you enter your delivery address at checkout. |
| Item Package Quantity | 1 |
| Item Weight | 900 g |
| Item model number | RSLTDS750 |
| Manufacturer | Ronseal |
| Material | Tin |
| Part Number | RSLTDS750 |
| Product Dimensions | 11.9 x 10 x 9.9 cm; 900 g |
| Size | 750ml |
| Style | Compact |

## Product Details

- **Brand:** Ronseal
- **Item dimensions L x W x H:** 11.9 x 10 x 9.9 centimetres
- **Item weight:** 0.9 Kilograms
- **Material:** Tin
- **Style:** Compact

## Images

![Thompsons Damp Seal 750Ml – Permanent Damp Protection For Walls And Ceilings, Easy To Apply, Quick Drying, White Finish, Optimal For Interior Use Before Painting - Image 1](https://m.media-amazon.com/images/I/71GbaqBJ5RL.jpg)

## Customer Reviews

### ⭐⭐⭐⭐⭐ Effective if used properly
*by F***E on 19 August 2023*

I have used this product previously to help prevent external damp from penetrating too far into a bedroom wall which was on the front elevation of our house. The house was built 1895 and the bricks used to soak up the wet all through the winter and tend to dry out through summer - a continuing cycle. Unfortunately the dampness - while slowly drying out - would permeate through to the inside wall surface, leaving residual marks and causing wall paper to decay and peel. We stripped off all the paper, scraped the wall then applied 2 heavy coats of this product to the wall, waiting a full day between coats. Yes, the coating does smell! It’s spirit-based, it needs to be to prove so effective. We overpainted with anti-condensation paint (2 coats) then standard ‘endurance’ emulsion and have had no further staining for the past 3 years. It is great for what it sets out to do. It is not effective when preparation is not done well, or done at all, but it is excellent for the job we asked it to do.

### ⭐⭐⭐⭐ Good product
*by S***E on 9 April 2013*

Good product that does what it says on the tin. Has sealed a slightly damp wall. Lets hope the rain stops some time soon!

### ⭐⭐⭐⭐⭐ Very Good 100% Recommended.
*by X***Z on 17 November 2024*

Very Good 100% Recommended. the best damp seal on the market, fast dry 4h job done. no smell like another .

## Frequently Bought Together

- Thompson Tds750 750Ml Da mp Seal
- Harris Essentials Walls & Ceilings Paint Brush Set | Pack of 5 | 0.5", 1", 1.5", 2", Grey
- Fit For The Job 10 pc Mixed Sizes Paint Brush Set for a Smooth Finish with Emulsion, Gloss, Satin on Walls, Ceilings, Woodwork, Metal - 2x 0.5, 3x 1, 3x 1.5, 2x 2 inch Paint Brushes for Wood, Plaster

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*Product available on Desertcart Thailand*
*Store origin: TH*
*Last updated: 2026-02-22*