Defender® Post and Wire Strips are the favourite bird-proofing system recommended by architects, especially on listed and historic buildings. The reason for this is due to the low visibility of the wire from the ground. Traditionally, Post and Wire was a complicated system that required drilling and specialist tools. However, Defender® Post and Wire negates the need for all specialist knowledge and equipment.
Step 1 - Clean the Area: Before you begin, the area needs to be properly cleaned to ensure the Defender® Post and Wire strips can be siliconed securely to the surface and not stick to any loose debris. Scrape and brush any loose dirt off the ledges. We recommend using warm soapy water and a disinfectant spray like
Germ Clear™ Bird Droppings Disinfectant Spray especially if the ledges have pigeon or seagull droppings on them. Leave the area for 24 hours to fully dry.
Step 2 – Spacing: Work out where you are going to place the strips - 2 rows of strips is ample to use for a ledge up to 2 metres long. The strips are placed with the double-headed post as close to the leading edge as possible with the anti-topple feet pointing towards each other to aid stability. If the width is smaller or wider than a strip, it can simply be broken into smaller pieces or additional pieces added to the row.
Step 3 - Silicone: Use Defender® Fixing Silicone Adhesive to glue the Defender® Post and Wire Strips into position. It is important to check the suitability of surfaces for use with Defender® Silicone. Always do a tester of one strip if you are unsure. For more information, please visit the product page
Defender® Pigeon Spike Fixing Silicone. Press the strips into position allowing for the silicone to ooze through the silicone locking holes, creating a strong bond and lock. Continue to silicone into position all the strips along the ledge or surface that is being proofed. Leave for 24 hours to cure before starting the wire install.
Step 4 – Attaching Wires: Working towards yourself, wire up every post including the double-headed posts on the leading edge. Unravel enough wire to cover the length between the posts allowing for a little extra for attaching and crimping. Thread a single crimp onto one end of the wire, then through the closed loop on a spring. The wire is then threaded back through the crimp. Push the crimp closer to the spring and using the crimping tool, squeeze the crimp shut, creating a secure tight fix, and locking the wire into position. Attach the spring to the eye in the post using the open loop on the spring.
At the other end of the wire, thread on another crimp and then through the opposite post's eye. The wire is then pulled through the eye in the post and pulled taut, but not so taut that it causes the post to lean inwards. The wires have a little bounce in the perfect install. Push the end back through the other crimp and push the crimp closer to the post, then secure using the crimping tool. The ends of the wires can be trimmed leaving 2.5 – 5 cm spare. Add a wire to every post along the strip and alternate the side the spring is attached.
Step 5 – Lengths longer than 2 metres: Two metres is the maximum length the wire can be run between 2 rows of Defender® Post and Wire. For longer lengths more rows can be added, each up to 2 metres distant. Wire up the first two rows as described above. You do not need to add an additional strip to the centre if you need 3 rows. The eyes in the centre row can be used again and are double-stringed. Again, alternate the spring. If one side already has a spring attached, start with just the wire and vice versa. The third row should be installed with the anti-topple pins facing the other rows.
How to Calculate Which Pack Size to Buy
Simply measure the length of the ledge or area to be proofed in metres and multiply it by the width.
Example 1 A flat roof is 8 metres by 0.74 metres so 8 X 0.74 = 5.92 m²
Therefore a 6 m² pack is required.
Example 2 A wall top is 5 metres long by 0.25 metres wide so 5 X 0.25 = 1.25 m²
Therefore a 2 m² pack is required.
Remember the bases can be easily made smaller by snapping between your fingers so every size length ledge or space can be fully protected.
NOTE: If you need advice on which pack size you need for your install, please do call us on
01626 835055 or send an email to
sales@jonesandson.co.uk