A capping strip (also called a capping or cover strip) is a strip or profile fixed to the top of wall sections, parapets, garden walls or window frames to protect the material below from water ingress and weathering.
Why use a capping strip?
Horizontal surfaces in masonry and concrete are vulnerable: rainwater sits on them and penetrates through joints and cracks. A capping strip ensures water is shed and does not soak into the construction.
Without capping:
- Frost damage can occur as water freezes inside the masonry
- Efflorescence may appear as salts are washed out
- The masonry weathers more rapidly
Application
Capping strips are used on:
- Garden walls and parapets — a lead, zinc or plastic strip on the wall top
- Copings — precast concrete or natural stone copings also serve as wall capping
- Window frames — a capping profile on the top of the frame prevents water infiltration
- Cavity walls — a cavity tray or DPC strip at the top of the cavity
- Masonry during construction — temporary sheeting to protect fresh brickwork
Materials
- Lead — traditional, long-lasting
- Zinc — lightweight and corrosion-resistant
- EPDM — flexible rubber, easy to install
- Plastic — affordable, limited lifespan
- Natural stone or concrete — as precast wall copings
Related terms
- Lead
- Wall coping
- Parapet
- Masonry
- Waterproofing
Want to learn more about construction terms? Visit our knowledge base at fredsdiyplans.com.