Roofs are the part of a building that are most exposed to intense elements – fluctuating temperatures, powerful sunshine, hail, rain, or even strong wind uplift – all of which gradually damages a roof over time. The lifespan of a roof depends on the type of material used, climate, orientation and other factors. The average roof can last anywhere from 15-30 years, whereas the average building lasts between 50-100 years – meaning that every building will need at least one roof replacement or repair in its lifetime.  

Metal Roof Repair

Metal roofs are one of the longest lasting roof systems but still are frequently in need of repair. Older metal roofing may need repair due to:

  • Metal corrosion
  • High metal expansion and contraction over time, leading to loose fasteners and cracks in seals and joints
  • Condensation
  • Storm damage
  • Leaks related to the waterproofing of difficult details, joints and connections or poor installation (especially at areas such as inner gutters, sky-lights etc.)   

Suitable Sika Systems for Repair of Existing Metal Roofs are Designed to Solve All the Above Problems:


Metal roof before renovation repair


Metal roof after renovation repair with single ply roof membrane


Bituminous Membrane Roof Repair

Repairing old, existing bitumen roofs is by far the most common type of roof renovation project.

Sika’s Roof Repair Solutions Have Many Advantages Compared to Traditional Bitumen Reroofing

  • Longer life-expectancy and guarantees
  • Availability of light colored reflective membranes which reflect heat and light, thus saving energy and costs
  • Lower additional load on the structure - the additional weight of Sika single-ply or liquid-applied waterproofing is much lower than several layers of bitumen that would be required for the job
  • Considerably higher flexibility and elasticity in cold temperatures
  • No risk of fires during application due to the totally flame-free installation methods
  • Increased fire resistance of the waterproofing system itself


Full Range of Systems Ideally Suited for Bitumen Roof Repair Projects

Comet hangar roof before renovation of bitumen roof


Comet hangar roof after renovation of bitumen roof


Roof Repair with Single-Ply Membrane

Mechanically-Fastened Systems with Sarnafil® / Sikaplan®

Mechanically-fastened roofs are usually the most cost efficient solution for polymeric sheet membrane roof renovation projects with many advantages:

  • Sarnafil® T polyolefin membranes are resistant to bitumen and can be applied directly on top of the old bitumen waterproofing
  • The fastest installation speed is achieved with mechanical fastening
    Sarnafil®and Sikaplan® membranes for mechanical fastening have special polyester reinforcement, enabling high wind load resistance
  • Installation is almost non-weather dependent

Adhered Systems with Sarnafil® / Sikaplan®

Sarnafil® and Sikaplan® adhered roofing systems are designed specifically for
roof renovations, making them the number one choice for re-roofing bituminous roofs for many reasons:

  • Bitumen compatible membrane
  • Membrane and insulation adhesives with excellent adhesion directly to bitumen
  • No penetration of the existing roof build-up is required
  • Very low noise emissions during installation
  • Easy application on simple and complex roof shapes
  • High aesthetic appearance and visual improvement
  • Many design possibilities with coloured membranes and profiles

Roof Repair with Liquid-Applied Membrane

Advantages of Liquid-Applied Membrane (LAM)

LAM is a highly efficient method to install a new waterproofing layer on
irregularly-shaped roofs within a short application time. Newly developed low-odor LAM technology enables installation even in dense urban areas, where torch-on bitumen is prohibited, and for buildings that need repair while still in use without the need to close down the facility (for example, in hospitals or schools).

Applicators applying liquid applied membrane to corrugated metal roof in protective clothing

Liquid-Applied Membrane Systems with Sikalastic®

Sikalastic® liquid-applied systems provide many advantages:

  • Cold-applied – no flame, no heat
  • Seamless roof waterproofing membrane
  • Fully-bonded to the substrate
  • Wide range of color selection
  • Available in white, highly reflective color, which is ideal for cool and solar roofs
  • Easily recoated when needed – no stripping required
  • Highly elastic and crack bridging – retains flexibility even at low temperatures
  • UV stable and resistant to yellowing
  • Ideal for renovation – provides a cost efficient life cycle extension for failing roofs
  • No penetration of the roof deck required
  • Vapor permeable – allows the substrate to breathe
  • Ideal for exposed roofs with a lot of complex detailing and penetrations
  • Easy and fast installation even at complicated details