These additional voids are a result of routine repairs and mechanical retrofits which naturally have happened a greater number of times in older vs. newer buildings.
Original Hardwood Floors
Original (or simply older) hardwood floors naturally warp, shrink and crack over time, and this creates gaps for insects. The risk is greatest in the case of hardwood floors which are installed directly on top of floor joists (as opposed to being laid on top of a subfloor).
It’s also possible for newly installed hardwood floors to have large gaps if the boards were installed before the moisture was allowed to equalize with the room. Typically, hardwood floors are left in the room where they’re being installed for at least a week prior to the installation in order to facilitate moisture equalization.
We’ve even seen instances where newly installed floors in brand new buildings end up having egregiously large gaps between each floorboard. While the floor likely looked fine when it was installed, the gaps appeared as the wood naturally contracted while releasing moisture.
Had the contractor allowed the wood to acclimate to the room and appropriately tested the wood with a moisture meter prior to installation, the risk of this happening would have been much lower.
The intersection between baseboards and hardwood floors is a common entry point for insects. While the perimeter of a room where the floor meets baseboards can easily be caulked, the natural seasonal expansion and contraction of wood often cracks caulking and creates new crevices for insects.
Retrofit of HVAC Systems
If any apartment in the building installs a new HVAC system, new conduit lines will have to be run from the compressor (which is most likely on the roof) directly into the apartment. This may necessitate several new exterior penetrations of the building’s facade or roof membrane, in addition to opening walls within the unit itself.
Based on our experience with contractors in NYC, the odds are extremely low that the construction crew will completely seal any old penetrations and fill 100% of any voids/holes created from the new HVAC system installation. If there’s just one crack or opening, vermin can enter the building and/or your apartment.
Radiator Steam Pipe Repair
Routine radiator repair work typically results in some movement to the riser pipes, and this can loosen surrounding caulking and flanges. This creates an entry point in your apartment for roaches who are traveling up the riser pipe from the basement.
Kitchen & Bathroom Plumbing
The walls surrounding kitchen and bathroom water and drain pipes are rarely perfectly sealed in pre-war buildings due to the sheer number of repairs which have likely taken place over the years. In our experience, plumbers in NYC typically pay very little attention to sealing any cracks or crevices around pipes. As soon as the leak is fixed, they’re usually out the door having done nothing more than a very minimal sweeping of large debris.
In addition to wall crevices surrounding pipes, it’s common for there to be gaps or holes in the drywall behind kitchen cabinets.