What a rat burrow actually looks like.
A rat burrow entrance is smooth-edged and roughly the size of a tennis ball, distinctly different from the rougher, smaller holes left by voles or the larger, messier digging of a groundhog. Often there is a worn, packed-down path leading to the entrance, showing regular use. Fresh burrows tend to have loose soil near the opening, while an older, abandoned burrow may show grass regrowth or debris settled into the entrance.
Sheds and decks are common burrow locations because they provide overhead cover from predators while the rat digs and travels underneath. A deck close to ground level, or a shed with a foundation that has settled and left a gap, gives rats an ideal combination of shelter and easy digging.
| Sign | Likely cause | What it means |
|---|---|---|
| Smooth, tennis-ball-sized hole with a worn path | Active rat burrow | Ongoing use, likely connected to a larger network. |
| Gnawed decking near ground level | Rats testing or widening an entry point | Check for a nearby burrow or foundation gap. |
| Grease smears along a foundation edge | Established rat travel route | Rats using the same path repeatedly. |
| Multiple small holes in one area | A burrow network with several entrances | Treat as one connected problem, not separate holes. |
Why rats choose a particular yard.
Rats need three things: shelter, food and water, and a yard that offers all three close together becomes an attractive burrow site. In Fairfax, that often means a property near Accotink Creek, Daniels Run or connected drainage, where water is close by and vegetation provides cover along the banks. A yard with an unsecured compost pile, spilled birdseed under a feeder, or pet food left outside overnight adds the food component that keeps a burrow active.
A shed holding stored firewood or bagged mulch can double as both shelter and material a rat might use, though rats typically dig their own burrows rather than nesting purely on the surface the way mice do.
Is one burrow the whole problem?
Rarely. A single visible entrance is often connected to a larger underground network with multiple exits, sometimes spread across a wider area than the one hole suggests. Treating only the visible entrance while missing connected exits elsewhere in the yard means the rat, or others in the same network, simply use a different opening.
A thorough approach checks the full extent of the property, including fence lines, other structures and any area with dense vegetation, rather than assuming the visible hole is the only access point.
Not sure this matches what you are seeing? Describe it on the call and we will help you sort it out.
Call (888) 686-4821What not to do with a burrow.
Filling in a burrow entrance without removing the rat or addressing the food source that drew it there usually results in the rat digging a new entrance nearby within days. Pouring water or other substances into a burrow is not an effective removal method and can create other problems, including flooding a neighboring area.
Our rat control service treats burrows by identifying the network, removing active rats through trapping, and then addressing the entry point at the shed or deck foundation with proper sealing, rather than a quick fill-in that does not last.
Sealing under sheds and decks.
Once active rats are cleared, sealing the gap under a shed or deck with hardware cloth buried a few inches below grade prevents new rats from re-digging in the same spot. Our rodent exclusion service uses this kind of buried barrier method specifically for structures sitting close to ground level, since a surface-only seal is easy for a rat to dig around.
Reducing what draws rats back.
Beyond sealing, reducing the attractants that brought rats to the yard in the first place lowers the chance of a repeat. Securing compost with a lid, using a catch tray under bird feeders, and bringing pet food indoors overnight all remove part of the food supply that supports a burrow network. None of these changes need to be dramatic, but together they make a yard less appealing.
Seasonal patterns for outdoor burrows.
Outdoor rat activity in Fairfax often increases in fall, as natural food sources thin out and rats look for a reliable supply before winter. A burrow that seemed quiet over summer can become active again during this shift, even without any obvious new digging visible from the surface.
Our backyard and outdoor rodent control service is timed around these seasonal patterns when scheduling a visit makes sense for a property with a history of burrow activity.
Sheds versus decks: does the structure type matter?
A shed with a solid concrete slab foundation offers less digging opportunity than one set on gravel, bare soil or short piers, since a rat needs exposed ground to establish a burrow entrance underneath it. A raised deck with open lattice or skirting around the base gives a similar amount of accessible ground as an unsealed shed. A deck built directly against grade with no gap underneath offers less opportunity, unless the perimeter itself has settled and opened a gap over time. Knowing which type of structure you have helps set expectations for how much digging opportunity actually exists before an inspection even starts.
Rodents do not wait for a convenient time. Reach the line and we will get you on the schedule.
Call (888) 686-4821How burrow networks connect across neighboring yards.
A rat burrow network does not necessarily respect a property line, and a network that starts under one homeowner's shed can extend toward a neighboring yard, particularly along a shared fence line or a drainage easement that runs behind several properties. If you notice burrow activity along a fence line shared with a neighbor, mentioning that during the call helps a technician assess whether the visible entrance on your property is part of a larger network extending beyond just your own yard. That awareness can affect how completely the problem can be resolved.
Signs the burrow has already reached your foundation.
A burrow that starts under a shed or deck some distance from the house can, over time, extend toward the main foundation if food and shelter continue to draw activity in that direction. Watch for gnaw marks or small gaps appearing at your own foundation, particularly near a crawl space vent or utility penetration. Either sign suggests outdoor burrow activity may be starting to test entry points into the house itself rather than staying confined to the yard.
Sources and standards
Public guidance behind the advice on this page. It describes general practice and rules, not a claim about any one provider.
- CDC: How to Clean Up After Rodents: The public-health steps for airing out a space, wetting droppings with disinfectant instead of sweeping, and bagging waste.
- CDC: Hantavirus Prevention: The seal up, trap up, clean up approach to rodent-proofing a home that public-health guidance recommends.