Identification
Rattus rattus — also called the black rat or ship rat — is the smaller and more agile of the two Metro Vancouver rat species. Adults weigh 150 to 250 grams, with a slender body 16 to 21cm long and a tail longer than the body (19 to 24cm). Fur is sleek, dark brown to near-black on the back with a paler belly. The face is pointed, the ears are large and can be folded down to cover the eyes, and the overall look is much more athletic than the heavy Norway rat. Droppings are 10 to 13mm long with pointed ends, smaller and thinner than Norway rat pellets. Roof rats are exceptional climbers — branch to branch, pipe to soffit, utility line to roof — which dictates where you'll find them.
Habitat in BC
Roof rats occupy the upper half of the building envelope and surrounding tree canopy across Metro Vancouver. They nest in attics, soffits, eaves, wall voids along top plates, garages with high shelving, and inside mature fir, cedar, and big-leaf maple canopy adjacent to homes. Roof-rat pressure has expanded substantially in Metro Vancouver over the past two decades and is now dominant across Marpole, Kerrisdale, Oakridge, parts of Richmond, South Burnaby, and increasingly through New Westminster. Any home with overhanging branches within 2 metres of the roof line, aging soffit mesh, or an uncapped chimney in those neighbourhoods is a candidate. Roof-rat pressure is generally lower than Norway-rat pressure in the Downtown Eastside and Strathcona, where Norway rats dominate the ground-level niche.
Signs you have roof rat
- Scratching, scurrying, or light running sounds high in walls, in the ceiling, or in the attic after dark — typically 9pm to 3am.
- Droppings 10–13mm long with pointed ends, smaller than Norway rat droppings, found on attic joists, in soffit cavities, or on garage shelving.
- Grease rub marks along rafters, the tops of joists, or at the openings into soffit cavities.
- Gnawed holes in soffit mesh, vent covers, or the upper corners of garage doors.
- Visible sightings of rats running along overhead wires, fence tops, or branches at dusk.
- Nesting material — shredded insulation, chewed cardboard, fabric — concentrated in a specific attic corner.
Risk & damage
Roof rats carry the same public-health profile as Norway rats: leptospirosis, salmonella, and historically the most significant rodent-borne disease pressure in human history (Rattus rattus was the primary flea vector for bubonic plague — modern Metro Vancouver risk is essentially zero, but the species history reflects how capable it is as a disease vector). Contemporary BC risks are contamination of attic insulation, chewed electrical wiring as a documented fire cause, damaged HVAC ductwork, and contaminated stored goods in garages and attic storage. Because roof rats nest directly above living spaces, urine and droppings can infiltrate through ceiling pot-lights and attic-to-interior penetrations, a specific risk not as present with below-grade Norway rats.
Seasonality in Metro Vancouver
Roof-rat calls in Metro Vancouver run year-round but peak October through February when mature-canopy populations move into attics and soffits for winter shelter. Breeding slows but does not stop in our mild coastal winters — we pull pregnant females from attic nests every month of the year. Spring leaf-out doesn't reduce attic occupancy because an established nest is more attractive than reopened outdoor canopy. The 2025–2026 mild winter did not cull juveniles, and population pressure through 2026 is meaningfully elevated across Marpole, Kerrisdale, and South Burnaby.
Treatment approach
Roof-rat protocol inverts the Norway-rat approach — we start at the roof line, not the foundation. Full attic inspection, full soffit inspection, full roof-edge audit. Entry points are typically at soffit-fascia junctions, gable vents, uncapped chimneys, plumbing stacks, and wherever a branch bridges from tree canopy to roof. Exclusion sealing uses hardware cloth at vents, chimney caps, soffit repair, and tree-canopy trimming recommendations. First-generation anticoagulant bait stations (tamper-resistant, SGAR-compliant) are placed at attic nest sites and exterior roof-line hotspots. Snap traps deployed in attics where stations aren't appropriate. Two 15-day verification visits confirm resolution. We never use SGARs; we never use glue traps.
When to call a professional
Call when you hear scratching or running from the ceiling or upper walls, especially at night, when you find pointed droppings in the attic or garage, when you see rats on overhead wires or branches at dusk, or when soffit mesh shows gnaw damage. Roof-rat exclusion requires roof-line access that most homeowners don't have safely, and a roof-rat colony in an attic compounds quickly — litters of 5 to 8 pups produced multiple times per year. Don't delay on this one.
Prevention playbook
How to prevent roof rat in Metro Vancouver homes
- 1
Trim tree branches 3m from the roofline
Roof rats are climbing specialists — they use overhanging branches as direct routes to your roof. Cut every branch back at least 3 metres from roof edges, soffits, and gutters.
- 2
Screen roof vents and chimneys
Install 6mm galvanized hardware cloth over attic vents, bathroom exhaust terminations, and chimney openings (leave chimney damper accessible). Thin vinyl screening fails — use metal.
- 3
Remove outdoor fruit and bird feeders
Fallen fruit from apple, plum, and cherry trees sustains roof-rat populations. Pick up daily during fruiting season. Bird feeders — reconsider; they are documented roof-rat attractants in Metro Vancouver.
- 4
Cap ventilation pipes and weep holes
Roof-rat-specific entry points: plumbing stack vents (cap with weep-hole screen), dryer vent flaps (auto-closing type), and brick weep holes (stainless mesh inserts).
- 5
Monitor attic quarterly
Unlike Norway rats (ground-level), roof rats nest high. Quarterly attic inspections for droppings and gnaw marks catch populations before structural damage.
The Wild Pest service
See our Roof Rat treatment page
Transparent pricing, 60-day return guarantee, same-day response across Metro Vancouver. Every treatment is documented with photos and service notes.
Frequently asked questions about roof rat
How do I know it's a roof rat and not a squirrel?+
Time of day. Roof rats (Rattus rattus) are strictly nocturnal, active 9pm to 3am. Eastern grey squirrels are strictly diurnal, active 6am to 6pm — their thumping and bounding stops at sunset. If the ceiling activity is after dark, it is almost certainly a rat. Squirrel sounds are also heavier and more rolling; roof-rat sounds are lighter, faster, and more rhythmic.
Why does Marpole have so many roof rats?+
Roof-rat expansion through South Vancouver has accelerated over the past 20 years, and Marpole's mature tree canopy, 1960s-era bungalows with aging soffit mesh, and laneway-house conversions with complex roof geometries create ideal habitat. Our internal data shows Marpole roof-rat callouts up 22% year-over-year in 2026. Any Marpole home with canopy within 2 metres of the roof should expect pressure.
Can I just trim the trees?+
Tree trimming helps — we recommend keeping branches at least 2 metres from any roof line — but it is not a standalone solution. Roof rats also use utility lines, fences, and neighbouring structures to access roofs. Trimming combined with full soffit-and-vent exclusion and interior trapping is the effective combination. Trimming alone buys weeks, not months.
Are the pointed droppings really a reliable ID?+
Yes, in combination with location. Roof-rat droppings are 10–13mm, pointed at both ends, and almost always found high — attic joists, soffit cavities, garage shelving, top-plate wall voids. Norway-rat droppings are 15–19mm, blunt, and found low — floor-level behind appliances, in basement corners, along crawlspace vapor barrier. The two species rarely share a single dropping location.
Is attic insulation contaminated after roof rats?+
If the colony has been active for more than 30 to 60 days, yes — urine saturation and droppings make the insulation unhygienic and reduce its R-value. Replacement is not automatic but is often worthwhile, especially in homes considering a sale or an attic upgrade. We can quote attic decontamination and insulation replacement or coordinate with specialist contractors depending on scope.
What about the 2023 SGAR ban — does it change rat treatment?+
Yes, and meaningfully. British Columbia banned general-use second-generation anticoagulants in 2023 because they secondarily poisoned owls, hawks, and domestic pets — Metro Vancouver's raptor populations had measurably declined. Our protocol uses only approved first-generation anticoagulants in tamper-resistant stations plus snap traps. First-generation baits require multi-feeding over 5 to 10 days, which is why physical exclusion is now a larger part of the protocol than it was pre-2023.
Related species