Rust-Oleum LeakSeal
  • Rust-Oleum LeakSeal

Rust-Oleum LeakSeal


Rust-Oleum LeakSeal is an easy-to-use, rubberised protective utility coating designed to fill and seal leaks and cracks.

  • Paintable finish
  • Anti-rust/corrosion
  • Will not sag/drip
  • Ideal for use on gutters, roofs, flashing, ductwork, uPVC, masonry and concrete
  • Can be topcoated after 24 hours

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  • Aluminium
£14.87(ex. VAT)
£17.84 (inc. VAT)
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In Stock and Available for Delivery (See Delivery Options Below)


Rust-Oleum LeakSeal is an easy-to-use, rubberised protective utility coating designed to fill and seal leaks and cracks. It provides a water-tight, flexible seal that prevents moisture penetration, rust and corrosion.

LeakSeal dries to a semi-smooth, firm finish that will not sag or drip, and can be top-coated with water-based or oil-based paints after 24 hours.

Recommended Uses

  • Gutters
  • Roofs
  • Flashing
  • Ductwork
  • PVC
  • Masonry
  • Concrete

New Colours!

  • CLEAR - Perfect for masonry, concrete or visible substrates.
  • ALUMINIUM - Great for metal, i.e. air conditioning/industrial piping. 
  • WHITE - Ideal for uPVC windows and doors.

Techical Data

  • Gloss Level: Satin

Drying Times At 20°C/RH 50%

  • Touch dry: 20 - 30 minutes
  • Dry to handle: 45 - 60 minutes
  • Dry to recoat: Apply second layer LeakSeal after 15 - 30 minutes. Topcoated with water-based or oil-based paints after 24 hours.
  • Fully cured: 24 hours

Theoretical Consumption

  • 0,74 m² per aerosol at 65 µm dry film thickness

Practical Consumption

Practical coverage depends on many factors such as porosity and roughness of the substrate, size of the leakage and material losses during application.

Surface Preparation

Remove all dirt and debris from the area to be coated. Wash area with a detergent and water solution, rinse with fresh water, and allow the surface to dry thoroughly. Remove any loose paint or previous coatings with a wire brush or sandpaper. Lightly sand glossy surfaces. Wipe the sanded surface clean when finished. Test previous coated material for compatibility before use. A test spray on cardboard is recommended to obtain feel for spray pattern. Spray surface in short, even strokes. Hold can 8-18" from surface. It is recommended to apply a light first coat. The second coat can be applied heavier. Quicker build-up can be achieved by moving nozzle closer in to gap.

Application Conditions

Use outdoors or in a well-ventilated area such as an open garage. Apply when temperature is between 50ºF and 90ºF (10 - 32ºC) and humidity is below 85% to ensure proper drying. Do not apply to surfaces, when heated, exceed 200ºF (93ºC). Avoid spraying in very windy and dusty conditions. Cover surrounding area to protect from spray mist. Shake aerosol vigorously for one minute after the mixing ball begins to rattle. If mixing ball fails to rattle DO NOT STRIKE CAN. Contact Rust-Oleum for technical support. A test spray on cardboard is recommended to obtain feel for the spray pattern. Hold the aerosol 8-18” (20 - 45 centimetre) from the surface and spray in short even strokes. It is recommended to apply a light first coat. Apply a second heavier coat to ensure proper coverage. A thicker film can be achieved by moving the nozzle closer to the surface. Initial spray may have some foaming or bubbling, but will dissipate as the coating dries. For best results, apply 2 coats. Allow to dry 15- 30 minutes between coats.


  • If the valve clogs, twist and pull off spray tip and rinse in a solvent such as mineral spirits. Do not insert any object into can valve opening.
  • Wipe off tip when finished.
  • Clean-up wet paint with xylene or mineral spirits. Properly discard empty container.
  • Do not burn or place in home trash compactor.

 Please contact Rawlins Paints' Technical Support Team on 0113 2455450 (option 2) or send a message to [email protected] for more information.

Product Details

Data sheet

For Use By
Consumer Use
Interior / Exterior Use
Water / Solvent Based
For Use On
Application Method
Standard / Ready Mixed
Pack Size
Dry to Handle (at 20°C)
45 - 60 minutes
Dry to Recoat (at 20°C)
Apply second layer LeakSeal after 15 - 30 minutes. Topcoated with water-based or oil-based paints after 24 hours.
Fully Cured (at 20°C)
24 Hours
0.74m² per can
Max. Application Temperature
Min. Application Temperature
Shelf Life (from date of manufacture)
2 years from date of production in unopened cans, if stored in dry, well ventilated areas, not in direct sunlight at temperatures between 5° and 35°C.
Touch Dry
20-30 Mins
UN Number
UN Number
0,74 m² per aerosol at 65 µm dry film thickness
Base Type
Suitable For Use On
Suitable For Use On
Suitable For Use On
Suitable For Use On
Suitable For Use On
Suitable For Use On
Suitable For Use On
Application Method
Crack & Joint Fillers
Product Type
Fastest Delivery
Next Working Day
Colour Family
Colour Family
Colour Family
Colour Family

Customer agrees that before placing an Order, Customer has read and understood the most up to date Product Data Sheet for the Product. Where we have access to the Product Data Sheet from the manufacturer, we will either provide a copy on request, or include a link to the Product Data Sheet available on the manufacturer’s website. Customer further agrees that we have no liability for any errors or omissions contained within the Product Data Sheets. For more information, please see our Terms & Conditions of Sale.

questions Philip Commander on 2023-09-21 09:54:10

I have a narrow crack in painted (Sandtex smooth masonry paint) render across the house on the west/south facing side which is exposed to weather. The render is otherwise sound. Can I use Rust-Oleum leak seal spray to prevent damp ingress which has recently become a problem?

Answer from Rawlins’ Technical Team: 

While this can be applied to masonry for this application it would depend on the size of the cracks and if they are active or not. 

Please can you provide more information and pictures of the area in question to [email protected]

questions Barry Colins on 2021-01-29 08:35:02

I have rainwater ingress in the boot of my car from one of the original bodywork spot welded joints. Would this product be appropriate?

Answer from Rawlins’ Technical Team: 

This is designed to seal leaks and cracks but works best when applied to the outside ( area exposed to the weather) For this application assuming the area is metal, clean dry, sound and prepared as detailed in the Technical Data Sheet we can recommend Bullet Mega Mastic

questions Keith Talbot on 2019-09-25 03:56:37

Am I able to use the gutter repair sealant when the surface is wet ?

Answer from Rawlins’ Technical Team: 

No, the surface to be coated with Rust-Oleum LeakSeal should be clean and dry before application.

questions Natalie on 2019-07-09 08:40:47

We have one part of out gutter that is letting a lot of water out. Think the seal is damaged or loose. Would this work on that?

Answer from Rawlins’ Technical Team: 

Potentially depending on size of the issue, for a more robust paint on solution we would recommend Rust-Oleum Fillcoat Fibres Repair Kit.

questions Eric Adair  on 2019-05-10 10:28:21

The harling on my house has a number of fine cracks. Can this be used to seal then before painting?

Answer from Rawlins’ Technical Team: 

Depending on the actual overall condition of this harling substrate, and the extent of the hairline cracks, LeakSeal could be a solution. However normally for hairline cracks (especially if whole wall is being treated) then we could suggest Rust-Oleum Mathys Murfill Waterproofing Coating.

questions Peter Lapage on 2019-02-26 17:25:48

My roof has water ingress at the lead flashing. Is this the best to use to seal the flashing at the brick wall?

Answer from Rawlins’ Technical Team: 

Rust-Oleum LeakSeal may work here but Rust-Oleum Mathys Fillcoat Fibres would be a better option.

questions Adrian price on 2019-01-08 19:46:58

Would it be ok on 40 year old asbestos cement board / corrugated sheeting ?

Answer from Rawlins’ Technical Team: 

Rust-Oleum LeakSeal is for small patch repairs, if you are wanting to seal a small crack, or apply over a fixing/bolt then this should be fine for temporary protection. However, if you wish to coat the whole roof you would be better looking at something like GacoPro Roof Coating.

questions Gary cailler on 2018-11-22 18:32:56

I have a 3 year old shed that has started to leak water where the ash felt roof is seamed down the middle. Can I use your product to seal the seam to prevent further water leakage? Thank you.

Answer from Rawlins’ Technical Team: 

We would instead recommend Britannia Aquashield Emergency Leak Repair.


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Rust-Oleum LeakSeal is only available with the shipping and delivery timescales listed below - please do not contact our Customer Support Team with enquiries about alternative or earlier shipping and delivery times.

Saturdays and Sundays, as well as Bank Holidays, are not classed as working days.

Orders placed after the cut-off for this product will not be processed for earliest dispatch until 9am the next working day.

All delivery costs below are excluding VAT

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