Rat peaking through hole in building foundation wall

What Makes Our Rat Control Programs Effective

What Makes Our Rat Control Programs Effective?

September 22, 2019

Matthew S. Hess

Rat control shouldn’t begin with an infestation and then lead to a solution, although it quite often does. It should begin with prevention and stop infestations before they start. As our mothers always said, “An ounce of prevention is worth a pound of cure!”. The same is true for rodent control.

I’ve spent  nearly 20 years in this industry and worked for several different companies before I began to run my own. I’ve since purchased  three pest control companies and have a staff of over 15 team members. I quickly picked up on the things which did or did not work, during those years spent working for others, . One of the common things I watched fail over and over was rat control and mouse control. I still observe this of other companies on a regular basis today and we receive calls frequently regarding this issue.

It isn’t that these other companies are unable to kill rats but to prevent them in the first place is an entirely different thing. That’s what our customers have to say when they have used other companies who failed at rat control before they found us. Yes, they killed rats but they didn’t eliminate them or stop them from continuing to infest.

An Inhospitable Environment Prevents Rats

Several factors must come together to make the environment around and in your home or business unhospitable to rats. You’re probably wondering just what kind of environment is unhospitable to rats, right? Well, that’s a good question because it certainly seems like they will live about anywhere!

Rat Control and the Basic Necessities for Infestations to Flourish

Anything which attracts or otherwise supplies shelter or vitality to pests is called “conducive conditions”, a term with which we pest control professionals are well acquainted. To put it in the simplest language it means, “things which make pest problems possible”. There are three main categories of “conducive conditions”, and these are also known as the three things all pests require to survive and populate:

  1. Water/Moisture
  2. Food
  3. Harborage

From a broad perspective, you can clearly understand these three categories and why they are necessary not only for pest populations to flourish but to exist at all. However, I want to hone in on specific conducive conditions within these three main categories to broaden our understanding of why we have pest problems at all. More specifically we will address rats and why it is important to implement good control BEFORE there is an infestation.

Crawl space vent with hole chewed through center by rats seeking entry to crawlspace - found during rodent control inspection

Rat gnaw marks we discovered on crawlspace vent during rodent control inspection. Rodents use chewed holes like this one to gain access to structures.

Rat Control and Water

Every living organism requires water to survive. This is a fundamental truth we all likely learned in science class at a very young age. But just how much water does a pest require? We can only answer this question if we know which pest we’re speaking of. However, it’s the wrong question to be asking.  To begin prohibiting pest problems, we should ask, “How do I prevent pests from accessing water in or around my home or business?” This is a tough question to answer. Many pests don’t require straight water. Instead, they can consume enough water to survive from the food they eat. Yet, putting a stop to water access will certainly deter pests and rats are no exception.

Remember that ounce of prevention I mentioned earlier; you know, the one worth a pound of cure? It begins with eliminating water or moisture and means we must take a walk around the outside of your structure to perform an inspection.


We will start with what happens to the rain when it hits the ground. Where does it go? It must drain away from your home and not towards it. It is crucial that it sheds away from the structure otherwise it accumulates in the ground and even on the ground. This, in turn, causes hydrostatic pressures to build against the foundation resulting not only in pest problems and water seepage through the foundation, but possibly major foundation damage!

Next, we need to verify that the gutters and downspouts are functioning properly to carry water away from the structure and shed it a great distance away. Bends, breaks, improper pitch, clogged, leaking, loose and heavily aged gutter systems will be noted and possibly require a gutter specialist to make the necessary repairs.

If water of any kind runs toward your structure or accumulates and stands near the structure, this will aid in pest population growth. There are a thousand reasons why water might be draining toward the structure:

Reasons Water May Be Draining Toward Your Home, Business or Other Structure
  • Structure is below grade or grade does not have adequate fall away from the structure.
  • (Minimum 6-inch drop in 10 feet is usually sufficient).
  • Concrete, blacktop or other substrate not properly pitched for watershed.
  • Timbers and other landscaping barriers may retain water near the structure. These often require drainage ports to avoid serving as a retaining wall for moisture.
  • Gutter downspouts not connected to drainage pipes leading away from structure.
  • Gutters clogged and water overrunning gutters.
  • Heavy overgrowth of trees/shrubs or other vegetation not allowing proper ventilation and sunlight to penetrate and dry the ground.

These are just a few of the many possibilities for water retention around a structure but are among the top of the list as what we find on a regular basis. These aid in pest infestations more times than you can count. Some of them are not as easy to correct as others but none of them are impossible. Correcting these will begin the process of preventing not only rat infestations but pest infestations in general.

Crawlspaces and Basements

Inspections in the crawlspace or basement for moisture and water can be crucial to rat control. In many cases, moisture in the these areas is the cause of pest infestations. It could be that fixing issues like we mentioned around the outside might clear this moisture up as well. However, if it doesn’t, we’ll need to figure out why it’s wet down there.

Leaks and Drips

We inspect for wet pipes, drips, damp duct work and/or air leaks from your HVAC (air leaks can transfer moisture from inside the home to the crawl and vice versa). Old metal ductwork without proper mastic sealant and insulating wrap can also cause moisture issues. Next, we need to verify that the dryer vent exhausts OUTSIDE the crawl.  Otherwise, it is transferring all the moisture from your clothes to your crawlspace!

Foundation Leaks

Now we must inspect the foundation walls for wet or water-stained areas and cracks/gaps/deteriorated areas. This will pinpoint where any water may be entering the crawlspace from outside and help aid in re-routing watershed around the perimeter of the structure. Sometimes, underground springs are the culprit and those take special skills to re-route. Other times it may be as simple as moving landscape timbers and other products which can act as a dam.

When parts of the landscape act as a dam, water may build up until it finds a point of release. That point of release may be a rodent burrow which leads to the foundation. Now the water has direct access to the foundation! A multitude of other variants come in to play here. We simply try to figure out which ones!

Other Signs of Infestation

While we’re in the crawlspace or basement, inspecting for rats, rat grease stains, droppings, carcasses, nests and typical damages and other signs is important. Finding entry points allowing rats which are outside the crawlspace to enter must be repaired. Entry points from the crawlspace to the living quarters also need repaired. Generally, these are found around plumbing penetrations at sinks, showers, tubs and other drains, pipes or wiring. These fall under the “Shelter” category but are addressed while we inspect for moisture in the crawlspace.

Additionally, other pests such as insects are important as well since rodents eat insects. While these fall under the “Food” category, since we’re already in the crawlspace it’s best to find those at that time. Before we move to the inside, we like to take a look at the surroundings and locate any potential areas of concern away from the structure. We will cover this under “Harborage”.


Now that we’re inside, we need to inspect all water sources to ascertain any leaking, sweating or other moisture. Under the sinks, behind the toilet, around the bottom of the toilet, around the showers and tubs, around the water heater, at your HVAC drain-line and anywhere else you have running or draining water will need to be observed for moisture to verify there are no drips, sweating, puddles or unwanted running water.

If anything is discovered, hiring a licensed plumber may be in order. If nothing is found we can move on to windows, doors, chimneys and vent-pipes through the roof. Inspecting all windows and doors for moisture around the edges, against the wall beneath and beside the windows, the floor beneath doors and windows and any staining, warping, bubbling, soft spots, rot or other signs must be performed. If anything is found it may need to be repaired.


Now we head to the attic and look for any signs of moisture there. This might be seen as staining to insulation or wood members and would be most likely found around chimneys, vents and plumbing exits. While we’re there we will look for signs of rodents including burrows, droppings, food sources, nesting, carcasses and other signs. While these belong to the other two categories, we will observe them while in the attic.

The Well Trained Rat Control Specialist

There are many more aspects of an inspection for moisture than we have time to discuss. To go over every detail would take more time to write than to perform. A well-trained rat control specialist on our team  might only need to quickly glance at a structure to note multiple deficiencies.

Do Your Own Moisture Inspection? Nah!

You could choose, at this point, to do your own moisture inspection and have quite the template to get started! However, we always recommend hiring a professional pest company to perform such a detailed inspection.

Such detailed inspections are what our service technicians here at Four Seasons Pest Solutions are here to do. We can make recommendations for all types of pest control and corrective structural modification programs which we offer. Rat control is just the beginning!

Rat Inspections are Second Nature to Pest Professionals

These inspections are second nature for us and therefore may be much tougher for someone untrained. The well trained rat control specialist can often spot these details with little effort.

Any of these water issues will certainly aid in rodent population successes. Eliminating these issues is a great first step in preventing not only rodent infestations but other pest problems AND structural damages and deterioration which can stem from inadequate moisture control.

We Specialize in Inspections

Here at Four Seasons Pest Solutions, we specialize in these inspections and often employ these techniques when implementing preventative rat control, pest control, termite control solutions and even crawlspace care solutions.

A crack in the transition area on a commercial structure found during a rat control inspection.

A quick look at this commercial building and its surroundings revealed a lot to be desired. For instance, the gap between the metal on this building (right side) and the block portion (left side). Not only can moisture enter, but insects and rodents as well!

The side of commercial structure viewed from the ground looking up. Taken during a rat control inspection.

Looking at the same building, we can see there are no closures OR rat guard at the bottom of this metal. Rat guard is essentially a trim piece of metal which would be secured to the building so that the vertical metal siding would rest against it. This prevents pest access to the back-side of the siding. Closures are simple rubber or foam molds of the contour of the metal siding which, when fitted behind the metal, block access to the back-side of the metal. Both of these should have been included on this metal siding install!

Cardboard stacked against commercial building in heavily wooded area discovered during rat control inspection.

In this picture (nextdoor to the building in the previous pictures) we noted several problems: Cardboard stacked against building allowing moisture retention, food source (for many pests) and shelter as well. Next we have garbage along the edge of the blacktop. Also, note the over-growth against the parking lot (though it is winter, you can clearly see the problem when summer arrives).

Light green house against elevated and wooded backdrop taken during rat control inspection.

Behind these two commercial buildings and in front of the rock wall we find this little home. Hopefully they aren’t dealing with the rat problems these two commercial accounts were, though they have every conducive condition surrounding them!

A Rock wall on a mountain side in the background behind wooded area during winter. Taken during a rat control inspection.

This rock wall against the mountainside and just at the edge of the wooded area will provide water, shelter and some food sources (mainly insects) for rodents. Taking note of the surroundings is important when implementing rat and other pest control!

Rat Control and Food

This category doesn’t usually take as long to identify. We’ve already inspected the attic, crawlspace and surrounding areas outside. The attic could yield such observations as nuts, bugs, seeds or other food sources and the crawlspace would likely yield similar results. The surrounding areas may have these same sources but may have others. These may include farm goods, garbage, partially digested food in animal feces, garbage and others.

Rodents are opportunistic foragers and I have personally found them feeding on small portions of undigested corn granules from undigested dog food in feces spread throughout a lawn. In that case, changing dog food to a grain-free option began to eliminate the population right away!

Open bag of dog food with stored items in the blurred background. Possible rat control issue.

An open bag of dog food, or even a CLOSED bag of dog food or other pet food, may provide not only a perfect food source for rodents but an attractant to draw them to the area. Pet food should always be placed in sealed, air-tight containers to prevent rodents and other pests. Pet food littered with rodent feces and urine is an unhealthy diet for any pet!

The bottom line with food is that if humans can eat it, rodents can too. And furthermore, even when humans can’t eat it, rodents may yet be able to!  This opens up such a broad range of sources that there isn’t enough time to mention them all. However, I will list several of the unusual ones I have seen throughout the years and then those we would expect.  Sometimes it’s not so easy to locate a food source!

Unusual Food Sources

  • Undigested corn bits from dog food in dog feces
  • Seeds on wreaths set out on shelves for sale
  • Insects
  • Soap
  • Corn-based (or otherwise plant-based) plastic on vehicle wiring
  • Plant-based plastic coating on child’s car seat
  • Other plant-based plastics
  • Food/plant dyed materials
  • Peppermint candy (Despite the fact that science observes that rodents do not like peppermint. We have observed that they will certainly eat it!)
  • Other dead rodents
  • Bodies of other animals (and, unfortunately for anyone who has ever witnessed it, human bodies as well)
  • Horse hooves
  • Potpourri (the kind that has various dried plant parts)
Rodent gnaw marks on the arm rest of a child's car seat. Taken during a rat control inspection.

Rodents had chewed on the armrest of this child’s car seat while it was in the vehicle in Louisville, Kentucky. There were very little shavings from the arm rest, leading us to the assumption that the plastic/rubber coating was likely plant based. Modern plant-based plastics and rubber can serve as a rodent’s food source in pinch!

Mmm… Corn Plastic, Anyone?

Animals can sometimes make a temporary food source from strange items. I once watched a couple goats eat styrofoam! As unrealistic as it sounds, it became very real when there droppings had styrofoam in them. Why animals eat odd things is outside of the scope of my knowledge. However, it does happen and we must be aware that a normal food source doesn’t always need to be present for an animal to survive.

A child's car seat with rodent gnaw marks on armrest. Taken during a rat control initial inspection and treatment.

Rodents can find a food source in some unlikely places. Thankfully, no children where hurt by this rodent problem. However, it is worth mentioning that these rodents were living INSIDE the vehicle this car seat came from. That in itself, is a serious hazard!

Close-up of a child's car seat armrest with rodent gnaw marks. Taken during rat control inspection.

Close-up image for clarity. Rodent gnaw marks are clearly visible on the arm rest of this child’s car seat. Potential food sources like these are often overlooked by homeowners,  and even some pest professionals!

Typical or Expected Food Sources

  • Pet foods (Dog, cat, bird, turtle, goat, horse, pig, etc.)
  • Human foods
  • Scraps
  • Food particles found in wrappers
  • Food particles in garbage
  • Any peanut-based candy
  • Seeds
  • Nuts
  • Crops
  • And many more

Finding available food sources (whether typical or nontypical) and eliminating or cutting off access to them, will not only help reduce or eliminate an infestation but prevent it altogether! Rodent control must include food-source elimination no matter in what point of the control it comes. Otherwise, rat control will fall short of satisfaction.

Our inspections include observing available food sources. We tailor our rodent prevention, rodent proofing and rodent control solutions to help eliminate all sources when possible. This sets us apart from the competition and makes our programs much more successful. Without food, why would you stay anywhere? A rodent must also eat and therefore won’t infest a food-free environment.

Rat control can be difficult when pets are fed free-choice food. Like this spilled dog food.

Observation in Rat Control is Key

I mentioned previously that our inspections also involve observing the environment around the structure. This includes even the drive to the structure. Observing what’s in the neighborhood or the general area and even the geography of the area often helps us understand why there are rodent issues or why rodent control or prevention measures might be necessary. Whether it’s a landfill, crop field, garbage dump, orchard, neighbor’s house/yard/barn, grain storage, feed mill, farm or other similar issues, discovering the potentially primary food source may prove crucial in proper rodent control and rodent prevention.

Limit a Rat’s Success

Rats  MUST have a food source for continued infestation, otherwise, their success will be limited. That’s where Four Seasons Pest Solutions’ thorough inspections prove second to none! If we can eliminate a food source or at least locate a food source before an infestation occurs we can help prevent it from ever occurring. It’s not difficult to kill rodents but to prevent them in the first place is a task best accomplished by experience and good training.

Bridge in background may play roll in rat control problem.


Whether its pest control, rodent control, termite control, bedbug control, flea control, wildlife control, roach control, or any other variants of pest control, harborage must be available. Just like you and I, pests of any kind need a safe and hospitable place to harbor. This might be you or me, a pet, our home, our workplace, a hole in the ground, void in a tree, inside a vehicle and a plethora of other places. We could never eliminate all the harborage areas for pests. But we can block access, make them inhospitable and set up barriers to intercept activity. Once a pest has set up harborage, infestation control must be performed. But what about preventing it beforehand? Of course, that would be the better alternative.

Prevention May Save Lives!

Preventing harborage, although taxing, can be rewarding in the future, especially when dealing with rodents. It only takes one rodent to chew into a wire, cause a fire and burn your house down around you while your family lay in bed, fast asleep. Of course, this is a worst-case scenario but a potential scenario nonetheless and maybe a more frequently occurring one than many realize.

Rat Control and Structure Fires

It’s estimated that around 20% of all undetermined structure fires are caused by rodents. That’s not counting the ones which are determined to be caused by rodents! I stress again that it ONLY TAKES ONE RODENT to burn a building to the ground. This is what makes rodent prevention and rodent control an absolute necessity when the potential threat for infestation is known or assumed. You can read more on this topic in my blog titled, Rodent Control and Modern Health Concerns.

Around a bridge like this one, there may be burrows around the foundation where large drainage rock is present. Inspection the surroundings help us identify where a problem may be coming from and the pest-load we may have to deal with in the future.

Rodent Harborage Areas

Rodents can harbor in a variety of places. As a general rule of thumb, if it provides any sort of shelter, even if temporary, a rodent can call it home. Below are several examples, though not an exhaustive list. You can probably think of many others as well, but for the sake of space, here are several important ones:

  • Homes
  • Barns
  • Abandoned buildings
  • Crawlspaces
  • Attics
  • Abandoned vehicles
  • Abandoned animal dens
  • Under rocks and in the ground
  • Under shrubs and bushes
  • Inside wall voids
  • Under cabinets
  • In cluttered areas
  • In wood piles
  • Near water sources
  • Near water sheds where pipe and rock are used to prevent erosion
  • And so many more that we just cannot list them all.

The list of places where rodents wouldn’t harbor is likely much smaller! There are a plethora of harborage scenarios available, but the primary concern is harborage within a structure.

Although it is important to pinpoint any potential harborage areas within a structure, it is equally important to pinpoint access points. An access point is a conducive condition which allows rodents easy access into the structure. In a commercial setting this might be something as simple as a dock door which is left open on a regular basis or an entry door where foot traffic occurs nearly non-stop. In a home, it can be similar but generally it comes down to two things; poor initial construction techniques or neglect of the structure over time.

Poor Construction

We don’t intend to run down or badmouth builders and contractors by any means. It’s not that they necessarily do anything wrong. Instead, we understand that they aren’t in the business of pest-proofing structures but rather, building them and supplying all the necessary components used to comprise a home. What this leads to is access points. These are areas where proper sealant or closure was not applied during the construction phase. Such areas may include but are not limited to:

  • Plumbing penetrations
  • HVAC line set penetrations
  • Poor or improper construction of crawlspace doors
  • Poor choice of crawlspace ventilation devices (Cheap vents)
  • Soffit-to-brick veneer or stone transition (leaves small gaps between mortar joints and soffit allowing mice to scale the brick and enter the attic)
  • Improper garage door installation (Failure to seal it properly)
  • Failure to install proper closure seals under metal roofing and ridge cap
  • Failure to trim trees away from the structure before building

This list can go on and on, but it’s easy to see that gaps, cracks, holes and so on, allow rodents easy access. Once in the home, reproduction and infestation follow. We button up these areas your construction team or repair guy may have left behind. It’s best to leave construction to the construction pros and pest proofing to the pest pros.

Neglect of the Structure Over Time

This one falls back on the owner (or previous owner)  and though access points left behind during the construction phase should not be blamed on the builder necessarily, neglect of the structure is certainly to be blamed on the occupant or owner. Neglect of a structure is among the leading causes of rodent infestation. If they can’t get in, they can’t infest! Therefore it is crucial that you do not ignore your structure through the years. Repairing areas which have minor issues prevent major issues later down the road. Such types of issues may include but are not limited to:

  • Rodent gnaw marks
  • Damaged siding
  • Damaged gutters
  • Damaged windows or doors
  • Small gaps and cracks
  • Any sort of moisture accumulation
  • Rot
  • Storm damage
  • Construction shortcomings (access points left by construction)
  • Leaks
  • And many others

Nearby Conducive Conditions

Any of these minor issues can turn into major issues and lead to major rodent infestations. Environmental conditions around the structure also pose significant risks when areas of access are readily available. As I stated earlier, environmental conditions away from the structure would be addressed under “harborage”. These issues can be as simple as a neighbor’s regularly uncut grass to as complicated as a river on the backside of the property adjacent to a rock wall. Sure, something can be done with the neighbor’s tall grass but you can’t move a mountain and a river… at least not because of rodents!

Other Nearby Conducive Conditions May Include:
  • Garbage dump sites, legal or illegal
  • Farm food production
  • Farm animal production
  • Feed mills
  • Food production plants
  • Heavily overgrown and brushy areas
  • Drainage ditches covered with large rocks
  • Rock walls
  • Bodies of water
  • Roadways with drainage areas
  • Railroad tracks (especially stopping points)
  • Shipping/receiving areas
  • Abandoned buildings
  • And the list just keeps going

We look at the surroundings to pinpoint areas of concern so that we might be able to better understand the impact the environment will play on potential or existing infestations. This helps us determine what measures must be implemented in you specific situation. Although we have a nearly full-proof method of rodent control solutions, we cannot underestimate the importance of specific conditions which may exist.

Hiring the right company to find these issues, fix what is fixable and implement a rodent control plan could be exhausting. However, we make it easy! We’re always here to help, when you can’t do it yourself.  Our Rodent Exclusion and Rodent Control Programs are aimed at finding points of interest, fixing those issues and preparing for future control measures. We know rodents cannot infest what they cannot access and we help make your home or business inaccessible to rodents and other pests.


What makes our rodent control programs effective? Knowledge! It takes knowledge to understand all the intricate details it takes to supply the demands of a rodent infestation. If you know these details, you can work to prevent each one individually and thereby prevent the infestation altogether. We know these details and apply them to all our pest control solutions including rodent control. Our work can help make your home or business that inhospitable environment it needs to be to pests seeking refuge.  Eliminating water, food and harborage will make any environment inhospitable to rodents! Implementing good rodent control measures before an infestation occurs stops an infestation from occurring!

Yellow clip art of a rat

It’s okay to live among pests… but you don’t have to live with them!