The internet is filled with suggestions of sealing baseboards to keep bed bugs in or out of a suite. But as always there are good ways and bad ways to perform a task. While I fully support the idea of sealing baseboards I suggest there are some basic guidelines that need to be followed.
Firstly, most people contemplate sealing baseboards after they have noticed bed bugs. Sealing baseboards in this setting simply ensures the bugs will find a neighbouring suite in which to emerge or they might instead be forced out of a light fixture several months later in the same suite. This is not very smart. Rather one should never seal baseboards until all evidence of live bugs are absent from the suite. The issues of delayed emergence of bed bugs and infesting other suites is then minimized.
Secondly the landlord should be directly involved in this process as tenants often lack expertise or ability to chose appropriate materials for the task at hand. I have a vivid memory of a tenant who ruined a historic 12 inch solid wood baseboard and hardwood floor with road tar applied with a stick. Also, cheap caulking will crack within 3 years, look hideous, and make the next attempt at sealing more difficult. Also, the tops of baseboards are often sealed more carefully than the bottom edge which prevents the exterminator from applying chemicals behind the baseboard but does not prevent bugs from harbouring in the baseboard. This is a case of doing more harm than good.
If you are going to seal a baseboard one should choose good quality materials and put a fair bit of effort in making a permanent seal. For example, in a historic apartment block with beautiful wood work one should remove the quarter round and fill the gap between the baseboards and floor with expanding foam. Once the foam is dry cut off the excess and reinstall the quarter round with no caulking. This way the foam product can cause a permanent flexible seal and the ugly caulking is not required. If bugs are noticed the exterminator still has opportunity to place chemical between the quarter round and the foam directly onto the place where the bugs are forced to hide. A perfect application of sealing.