Dow Corning and Geocel

Dow Corning’s range includes Dowsil silicone sealants, used widely for glazing, expansion joints, and external weatherproofing. Products like Dowsil 791 and 796 are designed for sealing around windows, curtain walls, and cladding. Geocel focuses on construction and roofing, offering sealants like Geocel 4500 which can be applied even in wet or damp conditions. Both brands cover a wide range of sealing needs for building professionals.

Yes, most Dow Corning and Geocel sealants are made for exterior use and hold up well in UK weather. Dowsil 791, for example, is great for sealing around external façades and handles rain, UV exposure, and temperature changes without breaking down. Geocel roofing sealants also resist cracking and stay flexible, even when exposed to the elements long term.

Dow Corning and Geocel sealants are made to bond with lots of common surfaces. You can use them on glass, aluminium, PVC, masonry, concrete, and coated metals. Some specialist products, like Dowsil 895 or Geocel Trade Mate Lead & Gutter Seal, are designed for very specific tasks and materials, so it’s important to check product compatibility if you’re working on unusual surfaces.

Yes, many products from both Dow Corning and Geocel meet UK and international building standards. For example, Dowsil 791 complies with ISO 11600 for façade sealing, which confirms flexibility and durability. Fire-rated and sanitary grades are also available where projects have safety or hygiene requirements.

Start by making sure the surface is clean, dry (unless using a wet-application product), and free from dust or grease. Use a caulking gun to apply the sealant evenly, then smooth it off with a tool or gloved finger before it skins over. Some jobs may benefit from using a primer to improve grip — always check the technical sheet for best practice, joint dimensions, and curing times.