KEDA · SILICONE SEALANTS

S300 Weatherproof Facade Silicone Sealant

Weathersealing for Facade and Exterior Joints

KEDA S300 is a silicone sealant intended for non-structural exterior joint sealing. It is positioned for facade contractors, installers and distributors reviewing a sealant for weather-exposed joints in the building envelope.

The focus is the weatherseal between adjoining components, not the attachment of glass, cladding or frames to the building. Product selection should consider the complete joint assembly and the project's performance requirements.

Application focus
Non-structural facade weathersealing
Selection starts with
Joint movement · substrates · exposure

Distributor enquiries & qualifying bulk orders

Product overview

01

Facade joints

02

Exterior weathersealing

03

Non-structural seal

04

Project specification

Product information

Product selection information
Application focusNon-structural facade weathersealing
Selection detailsJoint movement · substrates · exposure
Order requirementsConfirm supplied grade, colour, packaging and quantity

Request the current product instructions and confirmed supply specifications for your application.

Application selection

Applications to Discuss

  • Weathersealing joints between compatible facade panels.
  • External weatherseals in assessed glass curtain-wall systems.
  • Exposed perimeter joints around windows, doors and adjoining facade elements.
  • Replacement of existing exterior sealant after the cause of joint failure has been identified.

These application categories are not approval for every substrate or facade system. Identify the actual glass, metal finish, coating, masonry or panel surface on both sides of the joint before specifying the product.

Match the Sealant to the Joint

Provide the expected movement, joint dimensions and exposure conditions before selection. The word weatherproof does not establish a movement class, and tensile elongation alone is not a joint-movement rating.

Use the confirmed product performance and project design to determine joint geometry and backing requirements. Do not enlarge an application claim solely because another silicone product is approved for a similar-looking joint.

Check the Complete Material Combination

Review materials in contact with the sealant, including coatings, primers, backing materials, gaskets, tapes and adjacent sealants. Carry out the required adhesion and compatibility checks on representative project materials.

Natural stone and other stain-sensitive surfaces need separate non-staining assessment. Insulating-glass edge seals and laminated-glass edges also require specific compatibility review. Neutral cure does not by itself establish suitability for all these materials.

APPLICATION GUIDANCE

Start with the installation or care task.

Review the materials and application before choosing the supplied grade.

Explore Solutions

Application workflow

General Application Workflow

This overview is for planning. Obtain the actual product's instructions and SDS, together with the relevant project requirements, before application.

  • Review the joint and failure history. Confirm the selected product, substrate condition, expected movement and approved joint design. For replacement work, investigate the cause of failure before resealing.
  • Prepare the bonding surfaces. Remove old sealant and contamination by a method compatible with the assembly. Bonding surfaces must be sound, clean and dry. Use only approved cleaners and primers; do not assume a universal primer-free application.
  • Set the joint depth. Install compatible backing or bond-breaker material as required by the design. Avoid three-sided adhesion in movement joints. Keep designed drainage and ventilation paths open.
  • Apply a continuous bead. Use the specified dispensing method and fill the joint with adequate contact against both bonding faces. Avoid gaps, trapped voids and a thin cosmetic layer over failed sealant.
  • Tool and finish. Finish within the confirmed working period and remove masking tape while appropriate. Use only a tooling method permitted for the actual product; do not assume that soap solution or solvent is acceptable.
  • Protect, inspect and record. Protect the fresh joint as instructed. Distinguish skin formation from full cure and readiness for movement or testing. Complete the specified inspections and adhesion checks, and retain batch and application records.

Questions before ordering

How is S300 different from S200?

S200 is positioned around general window and door sealing. S300 is positioned around exposed facade weathersealing joints. This is an application distinction, not evidence that S300 has a higher movement rating or better performance in every situation. Select using the actual product data and joint requirements.

Can S300 bond curtain-wall glass structurally?

No. This page covers weathersealing, not the structural bond that secures glass. Structural glazing requires a separately specified adhesive, system design and project assessment.

What is its movement capability?

A verified movement classification is not available in this draft. Submit the project requirement for review. Do not use elongation at break or another manufacturer's classification as S300's movement rating.

Does neutral cure mean alkoxy, low odor or oxime-free?

Not automatically. Confirm the exact chemistry and relevant safety information for the supplied formulation. Neutral cure is not a substitute for those details.

Can it be used on natural stone or next to glazing gaskets?

Only after the relevant compatibility and, where applicable, staining assessment. Include the actual stone, coating, gasket, tape, backing and adjacent sealant materials in the review. Similar color or a generic material name is not enough.

Is a primer required?

The requirement depends on the supplied product and actual substrate preparation. Follow the confirmed preparation system and test results. Do not advertise primerless adhesion to all surfaces.

Can it be painted, or applied over old silicone?

Neither is established here. Select the joint appearance before installation. For replacement work, assess and prepare the existing assembly instead of adding a thin bead over failed material.

What colors and packaging can I order?

The packaging illustration shows a 300ml cartridge. Confirm actual capacity, available colors, carton quantity and supply conditions before ordering. A white cartridge does not indicate white sealant, and requesting another package does not establish its availability.

KEDA PRODUCT ENQUIRY

Discuss Your Facade Sealing Project

Send KEDA the joint drawing, materials and finishes, expected movement and weather exposure. Include the preferred color, packaging request, estimated quantity and any project-specific evidence requirements so suitability and supply options can be reviewed before quotation.

KEDA S300 Weatherproof Facade Silicone Sealant