Repairs to Common Entry Points

 

We have spent many years and have worked on thousands of cases of animals living in buildings in the Richmond area.  Some clear trends have come to light.  Listed here, in no particular order, are the most common ways we see animals enter buildings in this area.

 

Louver (gable) vents:  This is a common entry way for gray squirrels, flying squirrels, and bats.  Birds, raccoons, and black snakes also will enter this way, on occasion.  Gray squirrels start by chewing away the slats so that they can fit between them.  From there it is a simple matter to chew through the window screen on the inside of the vent.  Flying squirrels are small enough to fit between the slats and simply gnaw a hole in the screen.  Bats are tiny and easily fit between the slats.  If the screen is broken or loose, they enter the attic.  If the screen is solid, they are quite content to tuck up behind the slats and live in the vent itself.  Over time, the pressure they put on the screen usually breaks it. Birds and snakes generally only enter if the screen is already damaged.  Raccoons can use their great strength and dexterity to rip loose the slats, and then tear out the inner screen, although this is not common.

Solution:  It is best to rescreen louver vents on the outside with heavy steel mesh.  Screens are put on the outside to prevent gray squirrels from chewing the vent to pieces and to prevent bats from living inside the vent itself.  The screens are quite subtle, look like something that belongs on the house, and are attached with screws so that they are removable for painting and maintenance.

 

Chimney:  To many animals, a chimney is just like a hollow tree.   Squirrels and birds will go down chimneys and then find that they are unable to get back up the flue, leaving them trapped at the bottom.  Raccoons are able to climb in and out and will live in chimneys and raise their young there.  Chimney swifts, a small brown bird, can fly in and out of chimneys and will nest in them.

Solution:  A quality chimney cap should be installed on all chimney flues.

 

Fascia gaps:  It is a somewhat common practice for builders to leave gaps between the fascia boards and roof.  Since the shingles stick out past the gap, water does not leak in. These gaps encourage gray squirrels to chew holes by showing them that there is a hollow space on the other side, and by providing a starting point to get their teeth into.  This is one of the most common ways gray squirrels enter.

Solution:  Gaps which are hidden behind gutters are screened with heavy steel mesh. Gaps which are visible from the ground are covered with sheet metal which can be painted to match the house.

 

Foundation vents:  Foundation vents with damaged or missing screens are a common entry point for mice and snakes.  Mice will also chew holes in lightweight screens. 

Solution:  Foundation vents are rescreened using steel mesh.  Screens may be put on the inside or outside, depending on the style of vent and the lay out of the crawlspace.

 

Dormer corners:  During construction a gap is often left between the crown molding and the roof at the corners of dormer windows.  Since the gap is under the roof valley, they are protected from rain.  They do serve as common entry points for squirrels and birds, though.

Solution:  A piece of steel is cut to the right shape to fill the corner and is screwed into place. 

 

Rake boards:  On older brick houses, it is common for the rake boards to creep out from the brick, exposing a small gap.  This is, by far, the most common way that bats enter attics in our area.  Occasionally, we also find gaps between the rake boards and roof.

Solution:  Most of these gaps are small enough that they can simply be caulked.  Larger gaps are backfilled with steel mesh, then caulked.

 

Power fan vents:  The standard screens that come with these vents tend to be rather flimsy.  Squirrels and raccoons go under the vent’s hood and break the screen, and then enter the attic. 

Solution:  After experimenting with various methods to close these vents, we have found that the best system is to cover the entire vent, from the roof side, with a steel cage.  It can be seen from the ground, but is fairly subtle.  If a flat screen is put across the opening from inside the attic, it will keep animals from entering the attic; however, squirrels will use the screen as a platform to build a nest on, and will completely clog the fan.

 

Utility line holes:  Any time a hole is made in the foundation wall to run pipes or wires, there is a risk that extra space will be left around the pipe or wire, creating a small hole into the building.  The most common example is where the heat pump lines enter.  These types of holes are the most common way that mice and snakes enter.

Solution:  The hole is packed with aluminum mesh and then completely covered with caulk.

 

Eave/roof junctions:  Builders often leave gaps between the undersides of eaves and the roof, where two roofs meet (such as where one roof line meets another of a different pitch, or at cornices).  These gaps are a common entry point for squirrels and birds.

Solution:  Most commonly, we close these gaps using steel sheet metal, which can be painted to match.  Small gaps can be backfilled and caulked.

 

Final word:  It is impossible to completely animal-proof a building.  Squirrels (and other rodents) can chew through wood, aluminum, and vinyl.  Raccoons can use their great strength to tear up roofs, boards and vents.  Small animals such as bats, mice, flying squirrels and snakes can fit through tiny gaps.  Securing a building against animal entry is much like securing a building against burglars.  Reasonable preventative measures are taken to reduce the chance of break-ins, with the understanding that complete prevention is not possible.

 

Critter Control of Richmond provides service to the following cities:

Ashland | Chester | Chesterfield | Colonial Heights | Glen Allen | Henrico

Highland Springs | Hopewell | Manakin Sabot | Mechanicsville | Midlothian

Moseley | Petersburg  | Powhatan | Richmond | Sandston | Varina 

Call to schedule your home inspection