MOSQUITO BYTES NEWSLETTER

WHEN IT'S COLD OUTSIDE, RATS AND MICE TRY TO COME INSIDE

5 Tips to Reduce the Risk of Rats and Mice in Your Home
Recent cooler temperatures can prompt some Contra Costa County residents to bundle up and head indoors. It turns out, rats and mice will try to get indoors, too. They are warm blooded and naturally drawn to warmth, so when it's cold outside, they seek shelter. That's why it's important to take steps now so rats and mice don't use your home as their shelter.
Cold weather prompts rats and mice to seek shelter .
Rats and mice can spread disease through their waste products and can cause damage due to their constant gnawing. They've even been known to start fires as a result of their gnawing on live wires. They are attracted to a home and surrounding property due to the food sources and shelter opportunities that are available. To reduce the risk that rats and mice could use your home for shelter, follow these five tips from the Contra Costa Mosquito & Vector Control District (District):

  1. Inspect air conditioning units
  2. Repair missing, damaged or ill-fitting vent screens
  3. Store patio furniture and woodpiles carefully
  4. Replace weather stripping on exterior doors, including garage doors
  5. Remove climbing vines against the house and trim tree branches close to or over your home

Inspect Air Conditioning Units

"Rats and mice can sometimes find a way into your house thanks to your air conditioning unit," says District Supervisor Terry Davis.

"During installation or when you upgrade your unit, it is common for an installer to run lines into the home through a screened vent. It's important to check the vent and repair it to reduce the risk of rats and mice."

Davis adds, "There can also be a clear hose that allows condensation and excess water to drip onto the ground near the unit. If water remains puddled, it can attract rats and mice and can become a source for mosquitoes. Fill the puddle with gravel or rocks, to deter rats and mice."

Repair or Replace Vent Screens

As you inspect the vent screens near the air conditioning unit, periodically walk around the exterior of the rest of your house and take a look at the vent screens. Whether they are close to the air conditioning unit or not, missing, damaged or ill-fitting vent screens provide easy access for rats and mice. Repair or replace screens as needed to reduce the risk that a rat or mouse could easily access your home and put you and your family at risk of illness or harm. 

Store Patio Furniture and Woodpiles for Winter

When putting away patio furniture, including a grill, be sure to store them at least 18 inches away from a structure including a fence. And for the grill, be sure to clean it before storage, including the grease pan. Rats and mice have been known to seek shelter under a grill cover and find a food source on the grates and the grease pan. Davis says more than one homeowner has been unhappily surprised to discover a rat or mouse living in the grill once it's time to uncover the grill in the spring.

To store wood logs, use a log rack to keep the wood at least 12 inches off the ground and place the rack at least 18 inches away from a fence or structure to reduce the risk of rats and mice using the log pile for shelter.

Remove Climbing Vines and Trim Trees

Roof rats, which are commonly found in neighborhoods across Contra Costa County, are climbers. They use climbing vines to help them reach roof vents or broken roof tiles where they can find an entrance into a warm attic. They will also climb trees and can jump up to four feet from a standing position. By removing climbing vines and trimming trees that have branches that hang over the roof, you reduce a rat's access to look for a potentially out-of-sight entry point into your home.

Replace Weather Stripping

Not only can rats and mice enter a home through a vent screen, they can also gain access inside by entering through the space under exterior doors, including garage doors. They can easily enter through a hole created by gnawing on rubber weather stripping or a space that is created once weather stripping has worn out. Replacing rubber weather stripping with metal weather stripping not only closes the space that has opened, it prevents rats and mice from gnawing on it to create an opening.

Request District Service

If, after you have replaced weather stripping, repaired vent screens and trimmed tree branches you still notice rat or mouse droppings around your home, contact the District and request the District's service for rats and mice. District employees provide an inspection and assistance for rats and mice and can provide a written report when requested.

The District's mission as a public health agency is to protect the community from vectors of disease. Reducing the risk of rats and mice for Contra Costa County residents is an important part of that mission.
Contra Costa Mosquito & Vector Control District, an independent special district and public health agency, is located at 155 Mason Circle in Concord. Contact the District to report mosquito and vector problems online or at (925) 685-9301