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Fixed Roof Overhang – Blocking Marten Ascension Paths at Balcony & Facade

Scratching and scurrying noises at night often indicate the presence of martens on balconies, terraces, or near roller shutter boxes. By using non-toxic barriers, clean trail interruption, and targeted sealing of old wooden beams and cracks, ascension paths can be effectively blocked.

Step-by-Step Action Plan

1. Immediate Containment & Acute Security: Secure the balcony, terrace, and the area around the roller shutter box on the same day against further climbing. Remove mobile climbing aids such as stacked boxes, plant troughs directly against the facade, or leaning ladders. Close windows or ventilation gaps near suspected pathways at night and check old wooden areas for loose boards. Wear gloves and work only from a safe position, especially at facade edges and above head height.
2. Cause, Path & Nest Location: When hearing scratching and scurrying noises at night, first check transitions from the balcony railing to the facade, under the roof, and roller shutter boxes. Look for smooth, regularly used climbing edges, small fur traces, displaced insulation parts, or open cracks in the old wooden beams. Also inspect downpipes, climbing aids, and narrow wall projections that martens can ascend from the side. If an active resting place is suspected, seal the access only after careful inspection for young animals and current use.
3. Targeted Non-Toxic Control & Application: Install tightly woven protective mesh at critical entry points such as open ventilation gaps, cavities behind cladding, and accessible openings at the roller shutter box. Bridge joints at connections with weather-resistant sealing tape and additionally seal narrow cracks with elastic outdoor sealant. Lavender, tea tree, or cedarwood oil is suitable only as a supplementary short-term trail masking on already cleaned edge areas, not as a standalone solution. It is important that every measure stops physical ascension rather than just temporarily displacing the marten.
4. Hygienic Deep Cleaning & Trail Interruption: Thoroughly clean climbing edges, railings, window sills, and accessible areas around the balcony and terrace with a mild cleaning agent. This reduces scent marks and grease traces that martens can use for orientation. Ensure the cleaned areas are well dried before applying sealing tape, mesh, or sealant to ensure lasting adhesion. Scent oils should be applied very sparingly to edge zones only after cleaning and regularly renewed if weather conditions quickly degrade them.
5. Structural Sealing & Long-Term Prevention: Permanently secure the roof overhang by systematically sealing all recurring weak points in old wooden beams, connection joints, and cladding edges. The roller shutter box requires careful inspection for side entries, loose end strips, and unprotected gaps to the facade. Keep climbing aids such as dense climbing plants, high storage items, or directly adjacent branches at a distance from the building envelope. Plan a short night inspection over several days afterward to check if the scurrying noises have completely disappeared.
6. Swiss Professional Traffic Light (When to Call a Professional?): Red: immediately contact a professional if young animals are suspected, access continues in the attic, or safe work at height and facade is necessary. Orange: assistance is advisable if scratching noises continue at night despite sealing or multiple ascension paths exist simultaneously at the balcony, terrace, and roller shutter box. Green: self-measures are suitable if the pathways are clearly visible, the openings are small, and all work is safely accessible. A professional can also check if hidden secondary openings or structural weaknesses at the roof overhang have been overlooked.