What Is Overlashing?
Overlashing definition: attaching new fiber cable to an existing aerial strand with lashing wire instead of a new messenger. How it works and when it's used.
Overlashing is the aerial construction method of attaching a new fiber optic cable to an existing cable on the same messenger strand, using a lasher machine to spiral lashing wire around both cables together. It lets a carrier add fiber capacity to an existing pole line without installing a separate strand or new pole attachment hardware.
How overlashing works
A crew runs a lasher, a machine that spins a spool of steel or dielectric lashing wire, along the length of an existing aerial messenger strand. As it travels pole to pole, it wraps the wire in a tight spiral around the original cable and the new fiber cable together, binding them into a single bundle riding the same strand. The existing messenger and its pole attachments carry the added weight, so the crew does not run a new strand or add new hardware at each pole, provided the strand has enough remaining strength and sag capacity for the extra load.
When and why overlashing is used
Overlashing is common when a carrier needs to add fiber count on a route that already has aerial cable in place, such as a new provider entering a pole line, a network owner adding a redundant path, or a fiber-to-the-premises build riding an existing backbone strand. It is generally faster and cheaper than a new aerial build because it can skip a separate make-ready cycle for new strand and attachment points. It does not eliminate permitting: pole owners still need to confirm the existing strand can safely bear the added cable before work begins.
What to check before overlashing
Before overlashing, a pole attachment or engineering review confirms the existing strand's remaining capacity, current sag and tension, clearance requirements, and any conflicts with other attachers on the pole. Pole owners (utilities, ILECs, or joint-use associations) typically require an overlash notification or permit even though no new strand goes up, since the added cable changes the load on shared infrastructure. Skipping this step risks strand failure, code violations, or disputes with other attachers on the pole.
Overlashing, answered
What Is Overlashing?
Overlashing is the aerial construction method of attaching a new fiber optic cable to an existing cable on the same messenger strand, using a lasher machine to spiral lashing wire around both cables together. It lets a carrier add fiber capacity to an existing pole line without installing a separate strand or new pole attachment hardware.
How does overlashing work?
A lasher machine rides the existing messenger strand and spirals lashing wire around both the original cable and the new fiber cable, binding them together. The existing strand and pole attachments carry the combined weight, so no new attachment hardware is needed at each pole.
Overlashing vs. a new aerial build: what's the difference?
A new aerial build requires its own messenger strand and pole attachments, often triggering a full make-ready review. Overlashing reuses an existing strand's remaining capacity, which is usually faster and cheaper to permit and construct, but only works if that strand can safely bear the added cable.
Does overlashing require pole owner permission?
Yes. Even though no new strand is installed, pole owners typically require a permit or overlash notification before work begins, since the added cable increases load on existing attachments. Many pole owners use a shortened notification process compared to a full make-ready application.