J-B Weld Silicone Sealant & Adhesive – Waterproof RTV Silicone

J-B Weld Silicone Sealant & Adhesive is a general-purpose RTV silicone designed for sealing and bonding in household, automotive and mechanical assembly applications. Once cured, it forms a tough, flexible and waterproof seal that provides reliable protection against moisture and weathering.

RTV stands for Room Temperature Vulcanizing, meaning the silicone cures when exposed to moisture naturally present in the air. Once cured, J-B Weld Silicone Sealant & Adhesive creates a durable seal on most compatible surfaces without shrinking or cracking.

The cured silicone is waterproof and resistant to mould and mildew, making it a practical choice for applications where exposure to moisture or humid conditions is expected.

Its combination of sealing and adhesive properties makes it suitable for a wide variety of household repairs, DIY projects, automotive maintenance and mechanical assembly applications. The flexible silicone seal helps accommodate normal movement while maintaining a reliable barrier against moisture.

J-B Weld Silicone Sealant & Adhesive also offers good resistance to weathering, making it useful for suitable applications exposed to changing environmental conditions. Its sensor-safe formulation further increases its versatility for compatible automotive applications.

For anyone searching for a waterproof silicone adhesive, RTV silicone sealant, household repair silicone or automotive silicone sealant, J-B Weld Silicone Sealant & Adhesive provides a versatile solution for both sealing and bonding applications.

Key Benefits

• General-purpose silicone sealant and adhesive

• Suitable for both sealing and bonding applications

• RTV – Room Temperature Vulcanizing silicone

• Cures through exposure to moisture in the air

• Forms a tough seal once cured

• Waterproof

• Mould resistant

• Mildew resistant

• Remains flexible after curing

• Will not shrink

• Designed not to crack

• Resistant to weathering

• Sensor-safe formulation

• Suitable for household applications

• Ideal for many DIY repairs

• Suitable for compatible automotive applications

• Useful for mechanical assembly applications

• Creates a durable moisture-resistant seal

• Suitable for most compatible surfaces

How to Use

• Ensure the surfaces to be sealed or bonded are clean and free from dirt, grease, oil, old sealant and loose material.

• Prepare the surfaces as necessary to provide a suitable area for adhesion.

• Apply J-B Weld Silicone Sealant & Adhesive evenly to the required joint, surface or component.

• For sealing applications, apply a continuous bead to help create a complete waterproof barrier.

• For bonding applications, apply the silicone to the appropriate surface and bring the components together.

• Position the components correctly before the silicone begins to cure.

• Smooth the sealant as required before skin formation begins.

• Allow the silicone to cure through exposure to moisture in the air according to the manufacturer's instructions.

• Avoid exposing the repair to demanding service conditions until the silicone has properly cured.

• For automotive or mechanical applications, always follow the equipment or vehicle manufacturer's requirements for the specific repair.

• Always follow the application and safety instructions supplied with the product.

Typical Applications

• Household sealing

• Household repairs

• DIY projects

• Waterproof sealing

• Moisture-exposed joints

• General-purpose bonding

• Automotive repairs

• Automotive sealing

• Mechanical assemblies

• Workshop repairs

• Maintenance applications

• Applications requiring flexible silicone

• Suitable weather-exposed repairs

Product Information

Brand: J-B Weld
Product: Silicone Sealant & Adhesive
Type: General-purpose RTV silicone sealant & adhesive
RTV: Room Temperature Vulcanizing
Primary Functions: Sealing & bonding
Curing Method: Exposure to moisture in the air
Waterproof When Cured: Yes
Mould Resistant: Yes
Mildew Resistant: Yes
Shrink Resistant: Yes
Crack Resistant: Yes
Weather Resistant: Yes
Sensor Safe: Yes
Suitable Uses: Household, automotive & mechanical assembly applications
Primary Use: Flexible waterproof sealing and general-purpose bonding

Data Sheets:
Data Sheet
Data Sheet
Data Sheet
Data Sheet

WEEE Recycling Producer Registration Number:12889

How do I return my old product to be recycled?

You can return your old product to MyDIY. Waste Electrical and Electronic Equipment (WEEE) is taken back free of charge on a one-for-one, like-for-like basis. Waste batteries including rechargeable batteries are taken back free of charge. You are not obliged to make any purchase when returning old batteries. Each local authority must also accept household WEEE and small batteries free of charge at its recycling facilities. All WEEE and waste batteries must be recycled and should not be placed in any of your household wheelie bins. Make sure you always recycle all your old electrical goods and batteries.

What products can I recycle for free?

You can return anything that is electricaly powered or battery powered. Even your old bicycle lamps can be recycled!.

Do you take back used batteries?

Yes we do. The batteries that we accept are AA, AAA, C or D, powertool batterys and also the flat batteries that are found in watches and toys. Unfortunately we do not accept back any Industrial or car batteries.

Do I need to have made a purchase at MyDIY.ie?

No you don't. You can recycle any of the above items at our store in Inchicore Dublin 8, even if you have not made a purchase with us.

Will you collect my old product?

Yes, but we must be notafied within 14 days of purchase date. You can still arrange to have your old appliance recycled free of charge. Simply bring it back to our Inchicore store and we will ensure that it is disposed of in an environmentally friendly manner.

How much will it cost?

There is no charge to return products to any of our warehouses.

Why should I recycle with MyDIY?

We will ensure that your old product is disposed of correctly to reduce the potentially harmful effects caused on the environment and to conserve natural resources. Further information can be found on weeeireland.ie.

EMC (Environmental Management Cost) Included in the purchase price. 

Gas discharge lamps, LFLs and CFLs €0.15

LED lamps and luminaires €0.05

Large appliances €5.00

Information

Fast & Reliable Shipping with DPD

We ship all orders via DPD, one of Ireland’s most trusted couriers. With DPD’s one-hour delivery window, you won’t have to wait around all day for your MyDIY.ie order!

Delivery Times

Each product on our website is marked with an estimated delivery time. If you order multiple items, your order will arrive based on the item with the longest delivery time. For example, if you buy two next-day items and one 3-day item, the entire order will arrive in 3 days.

While most products arrive in 1-2 days, we offer over 44,000 items, so please allow 4-5 working days for some deliveries. Need it faster? Call us at 01-446692, and we'll do our best to help.

Delivery Charges

• FREE delivery for orders over €150 within Ireland.

• Orders under €150: €8.99 delivery fee.

• International delivery: Charges based on weight—contact us for a quote.

When Will I Receive My Order?

• Most orders ship on a 24-hour courier service (2 working days).

• Larger orders may take 4-5 days, and pallet deliveries require scheduling.

• Orders placed before 2 PM usually ship within 24 hours.

• Orders after 1:30 PM Friday or on weekends ship the following week.

• Busy holiday periods may cause slight delays beyond our control.

Do I Need to Be Home for Delivery?

Yes, someone must sign for deliveries due to item value. If you're not home, DPD will leave a card with re-delivery or collection instructions. After two failed attempts, your order may be returned to us, and a re-delivery fee may apply.

Damaged or Incomplete Orders

We carefully pack all orders, but if something arrives damaged or incomplete, contact us within 24 hours. Report shortages within 3 days of delivery.

International Shipping

We ship to Europe and worldwide, with charges based on weight. Liquid products cannot be shipped internationally due to regulations. Contact us for a quote—we're happy to help!

Customer Service & Returns