Keeping your building free of vermin

It's your responsibility to prevent and deal with rodents, bed bugs, mosquitoes, and pigeons issues.

Building owner responsibilities

Property owners must make sure their property does not have vermin. Vermin include rodents, bed bugs, pigeons, and mosquitoes. If your property has vermin, you could get a health violation. If you have many health violations, you might have to do a pest infestation and sanitation training.

Preventing vermin

Keep vermin out of your residential or commercial building. Some methods include:

  • Seal gaps more than ¼ inch around exterior doors and windows
  • Seal openings in exterior walls, especially around pipes or conduits
  • Seal holes with hardware cloth, copper mesh, caulk, sheet metal, concrete, or mortar


Rats and mice live wherever there are hiding places and easy access to food. Look for signs such as droppings, scratches, greasy rub marks, and tracks.

Make sure there are enough garbage containers that they do not overflow. Store all garbage in a container, not a plastic bag. Make sure your garbage containers:

  • Keep out rodents and insects
  • Be watertight with tight fitting lids
  • Are emptied often enough that they do not overflow

Thin out dense trees, vines, and shrubs that shelter rats, mice and mosquitoes. Remove or thin out dense groundcover that hide burrows, runways and clog drains. If you have stored materials you must be able to see if it is attracting rodents, insects or other wildlife. Stored materials include:

  • Crates
  • Pallets
  • Lumber
  • Tires
  • Firewood
  • Scrap metal
  • Store items stacked neatly in piles. Elevate piles at least 6 inches from the ground. They must also be 6 inches or more from any wall or fence.

Bed Bugs

Bed bugs are blood-sucking insects that can cause redness, itching, and swelling. Property owners and tenants share responsibility to prevent pest infestations. Property owners or managers must respond to tenant bed bugs complaints by hiring a licensed pest control operator. Bedbug treatment can take more than 30 days. Learn more about bed bug prevention and control with our resources.


Pigeon waste, feathers, and nesting materials can contain organisms that cause human disease. Pigeon waste also damages paint and building materials. Discourage pigeons by:

  • Removing food and water sources
  • Removing waste, feathers, and nesting material
  • Building sloping sills
  • Using nets, screens, or mesh made of wire or nylon
  • Using a timed sprinkler

Poisoning, trapping, or shooting pigeons is not allowed. Make sure to check with the San Francisco Fire Department before installing netting or making other structural modifications that might block access during an emergency.


Standing water leads to mosquitoes that can carry diseases such as the West Nile virus. Make sure you do not have standing water sources. Water will also attract wildlife, rodents, and other pests. 

  • Drain standing water, such as saucers below flower pots, hot tub covers, wading pools, hollow stumps, and trash containers
  • Stock permanent ponds with fish that eat mosquito larvae
  • Use pumps that circulate water
  • Clean out clogged roof gutters in the spring and fall
  • Maintain drains so they are clear of leaf litter
  • Cut back overgrown vegetation, especially in the shade
  • Do not over water your yard
  • Keep grass cut short
  • Let the ground and the soil in potted plants dry on the surface before watering
  • Use non-chemical insecticides such as Bti "dunks" if you cannot drain standing water
  • Use screens on windows and doors
  • Place mosquito nets over beds and cribs
  • Avoid outdoor activity at dawn and dusk
  • Wear long sleeve shirts and long pants when mosquitoes are active
  • Use DEET and permethrin products with caution, especially around children

Training staff

If you have building staff, you must train them to:

  • Make regular inspections for signs of pest infestation
  • Maintain sanitation and keep up with repairs
  • Respond to tenant reports and keep records
  • Safely handle, remove, and dispose of infested or contaminated materials

Dealing with vermin

Respond to vermin reports

After a tenant reports vermin activity, you have 72 hours to investigate it. You must keep a written log of any signs or reports of vermin such as:

  • Rodents
  • Fleas
  • Flies
  • Bedbugs
  • Spiders
  • Cockroaches
  • Wasps
  • Mosquitoes

You can use our complaint forms and log template. Give your log to the pest control operator.

Get rid of rodents

It can be very hard to completely get rid of rodents without professional help. We recommend using a pest service that licensed by the San Francisco County Agricultural Commissioner. Try to find a service that uses Integrated Pest Management (IPM). They can address the whole rodent problem and help you learn how to keep rats or mice from coming back. Snap traps can be effective if you use them right. Do not use poisons. Rodents can die in places that are hard to get to, causing odors and flies.

Remove dead animals and waste

Make sure to remove animal waste. Animal waste can spread disease and attract flies, rodents, and wildlife. It is also a source of odors. Wear disposable gloves and wrap the dead animal or waste inside 2 plastic bags. Avoid inhaling dust from droppings. Disinfect areas with a bleach solution (2 tablespoons bleach to 1 cup of water). If you need to remove large amounts of droppings, wear a dust mask.

Trapping mosquitoes

We may place mosquito traps on your property for a few days to find the mosquito source. We will work with you to deal with the problem.

Tell tenants about pesticide treatments

If a licensed pest control operator needs to use pesticides, tell your tenants the names of the products and the contact number for the Poison Control Center. Make sure you understand the State requirements.

Do not apply restricted pesticides. Only a licensed pest control operator (PCO) can apply restricted pesticides. Call the California Structural Pest Control Board at (916) 561-8704 to check the status of a company's license. The company must also be licensed to do business in San Francisco. Call 415-252-3862 if your PCO cannot provide proof.

Tenant responsibilities

Tenants must also work to prevent vermin. Tenants are responsible for keeping living areas reasonably clean and orderly. Keep garbage, pet food, and other items attractive to vermin properly stored. Do not put food out for wildlife or pigeons. Tenants must allow pest inspection and treatment. If a health inspector finds bed bugs, tenants must wash their clothing and bedding.

Last updated April 16, 2024