Soudal SoudaGum Hydro Hybrid Polymer Roof & Gutter Coating 5kg

Soudal SoudaGum Hydro is a ready-to-use waterproof roof coating based on hybrid polymer technology. It comes in a 5kg tub, ready to apply with no mixing required. As a waterproof roof coating, it handles the kind of jobs that catch out lesser products: ageing felt roofs, leaking gutters, cracked flashings, and exposed joints where water finds a way in if you give it half a chance.

The formula is solvent-free and isocyanate-free, which matters both for safety during application and for compatibility with a wide range of substrates. You get excellent adhesion on most common roofing materials without needing a primer on the majority of surfaces. It bonds to bitumen felt, metal, concrete, masonry, fibre cement, EPDM, and more.

One of the most useful properties on site is the 2-hour rain resistance. Apply SoudaGum Hydro and if the weather turns, you are not left hoping the job survives a shower. That short window before rain can ruin a freshly applied coating is one of the more frustrating aspects of flat roof work, and this product genuinely reduces that risk.

Where Soudal SoudaGum Hydro Earns Its Keep

SoudaGum Hydro is applied in two layers for full waterproofing performance. The first coat seals and penetrates, the second builds the protective membrane. The coating remains permanently flexible after curing, so it moves with the substrate through thermal expansion and contraction without cracking. This is particularly important on flat roofs and metal gutters where movement is constant over a year of temperature swings.

Once cured, the surface is paintable, which is useful where the finished appearance matters or where you need to apply a reflective topcoat. UV and weather resistance is good, so the coating holds up to prolonged sun exposure without degrading quickly.

WT1-Comparable Performance

SoudaGum Hydro is considered a practical alternative to liquid waterproofing systems classified under the WT1 category. It provides the kind of waterproof roof coating performance that works for repair and maintenance applications on existing substrates, without the cost or complexity of a full liquid-applied system. For roofers maintaining domestic and light commercial properties, that makes it a sensible option to keep on the van.

The 5kg tub gives you enough material for a meaningful area of repair work or a section of guttering, and the single-component format means no waste from unmixed components going off in the bucket. Clean tools with water before the product cures.

SoudaGum Hydro is produced by Soudal, one of the more established names in sealant and coating chemistry. The hybrid polymer base gives it a profile that sits between traditional bitumen coatings and higher-end polyurethane systems: better flexibility and adhesion than standard bitumen, without the solvent content or mixing requirements of a two-part PU.