Older buildings across Toronto and the GTA have a charm of their own. Many were built decades ago with thick concrete walls, unique layouts, and solid craftsmanship that you rarely see in newer simplistic/minimalism construction. The downside is that these same structures can create perfect conditions for bed bugs to move from one unit to another without anyone realizing what is happening.
Understanding how these pests travel inside older buildings can help property managers and residents react faster and protect their homes before a small problem turns into a whole building outbreak.
Why Older Toronto Buildings Face a Higher Bed Bug Risk
Many apartments in Toronto were built in the 1960s to 1980s (driven by a post-war housing boom). Bed bugs were not common at the time, so architects never considered bed bug movement when designing walls, ceilings, or shared systems. Today that old construction style gives bed bugs several hidden entry points.
Older buildings often have:
• Shared plumbing lines that run through multiple units
• Electrical conduits that connect rooms vertically and horizontally
• Gaps around radiators, baseboards, and door frames
• Unsealed cracks in plaster or drywall
• Hollow interior walls that allow insects to travel undetected
These small pathways act like highways for bed bugs. Once a population grows in one unit, it can quietly migrate into the units above, below, or beside it.
Electrical Systems Are One of the Biggest Hidden Highways
One of the most common routes for bed bugs in older Toronto buildings is the electrical system. Electrical outlets, switches, and light fixtures often share the same conduits within the walls. If there are gaps behind an outlet or switch, bed bugs can slip through the wall cavity. They then travel along the conduit until they find another opening. A resident may spot a bed bug in the bedroom, not knowing it came from an entirely different unit.
Plumbing Lines Also Allow Movement Between Units
Washrooms and kitchens in older buildings often share plumbing stacks. Behind the wall, there are open spaces around the pipes where bed bugs can move freely. Warm water pipes create friendliness for pests. The constant moisture and heat can also speed up egg development, especially in buildings that run hot.
Residents often ask how bed bugs ended up in the bathroom or kitchen. These are the rooms that connect directly to other units through the plumbing system, so they sometimes become first contact points when a neighbouring unit has a strong infestation.
Read our case study about how a homeowner who found they had a bed bug infestation in their basement through their vent system.
Baseboards and Trim Gaps Create Pathways Too
Over time, older trim expands and contracts, leaving small gaps. These cracks are perfect hiding spots for bed bugs. They also allow insects to move along the perimeter of rooms. Bed bugs often gather under baseboards before they start spreading elsewhere.
In many Toronto apartments, the baseboard gaps connect directly to the shared walls. If one side is infested and the insects feel pressure or overcrowding, they slip through and start establishing a presence in the next unit.
Why Bed Bugs Spread Faster in Older Buildings Compared to Newer Ones
Newer buildings often use sealed construction, and tighter gaps. Older buildings, on the other hand, contain countless voids and intersections behind the walls. When you combine these hidden routes with high resident turnover and shared laundry rooms, it creates a perfect storm for long distance bed bug movement.
Some older buildings also have fewer inspection protocols, allowing an infestation to grow for months before it becomes visible. By the time a resident notices bites or live insects, bed bugs may already be well established across multiple units.
Signs That Bed Bugs May Be Coming from a Neighboring Unit
Residents in older Toronto buildings should watch for these signs:
- Bed bugs showing up in unusual places like bathrooms or kitchens
- Activity concentrated on shared walls
- Bed bugs appearing even after a thorough cleaning
- Bites despite changing bedding and decluttering
- Seeing insects near electrical outlets or baseboards
- Detecting a sweet or musty odour near walls
When these signs appear, it often indicates movement from another unit rather than a fresh introduction to your own home.
Final Thoughts
Older Toronto buildings are beautiful, but the construction style gives bed bugs many opportunities to spread. Understanding these hidden highways can help residents take action early and avoid long lasting infestations.
