Why the crawlspace is the whole story in San Francisco
Ask a wildlife technician here where they start and they will tell you the perimeter, not the roof. That is a direct consequence of the weather. Winter lows averaging 46F are simply not cold enough to push an animal up into an attic, so the strongest denning motive in most cities is missing. What remains is a preference for dark and undisturbed, and a raised foundation delivers both at ground level. The openings are already there in the form of vents, and they were built to move air rather than to resist a 20 pound animal pulling on them. The practical effect is that problems go unnoticed for months. Nobody hears a crawlspace the way they hear an attic, and nobody opens it in between. By the time the smell comes up through the floor, the latrine is established and the duct insulation is gone. So the first job is a real inspection: every foundation vent, the access hatch, the base of the rear stairs, deck skirting, and the seam where an addition meets original framing. Ask how long that walk takes. Anything under half an hour on a city lot is a guess, not an inspection.
The April problem, and what a good company does about it
UC IPM puts California raccoon births in April and May, with litters of three to six and an average near four. Those two months decide the method, the cost and whether the job goes badly. Here is the failure people pay for. A one way door goes on the crawlspace vent in the third week of April. The mother is outside when it closes. She spends the next four nights tearing at skirting, siding and a second vent to get back to her kits, and the kits, too young to walk out, die where they are. Somebody then cuts the subfloor open from the room above. The alternative takes longer and works. The technician gets into the space, finds the nest, moves the young into an insulated box, and sets that box against the foundation at dusk. Female raccoons keep more than one den and normally relocate their litter before morning. When you call around during a San Francisco spring, ask one question: what do you do if there are babies. If nobody mentions locating the nest, keep calling.
What California law lets anyone do with a trapped raccoon
This is the part where promises should make you suspicious. UC IPM states plainly that relocating a raccoon is prohibited without written permission from the department, because California manages raccoons as furbearers with regulated seasons rather than as animals anyone can move at will. The reasoning behind rules like this across the country is disease containment. USDA distributes roughly 6.5 million oral rabies vaccine baits a year to hold the raccoon rabies front at the Appalachians, and CDC notes that raccoons make up 29 percent of rabid animals reported nationally. Hauling animals across county lines is exactly how a contained problem stops being contained. So when you interview companies, ask two direct questions. What license do you hold for paid nuisance wildlife work, and what does San Francisco require you to do with each animal you trap. A specific, slightly uncomfortable answer is a good sign. A cheerful promise about a nice spot in the hills is not. None of this changes what actually solves your problem, which is the eviction plus the repair. It only changes who you should trust to do it.
Cleaning the space after they are out
Removal buys you quiet. Cleanup buys you a usable crawlspace. A den in use for a month leaves three things behind: a pushed aside nest area, torn duct insulation, and a latrine concentrated in one corner of the soil. Because the fog keeps humidity around 75 percent for much of the year, none of it dries, and the odor works upward through the floor into the rooms you use. The hazard has a schedule. Roundworm eggs in raccoon droppings become infectious after roughly two to four weeks, per CDC, and once they do, common disinfectants will not destroy them. The material has to be bagged and carried out, the soil treated with heat rather than a sprayer, and contaminated vapor barrier and duct wrap replaced rather than patched. This is the specific job not to attempt with a dust mask and a shop vacuum in a two foot crawlspace, since a vacuum aerosolizes what you are trying to remove. When you read the quote, check whether removal, treatment and replacement of insulation and vapor barrier are inside the number or listed as options to be added later.
Reading two bids that are hundreds of dollars apart
Put the two quotes next to each other and cover the totals with your hand. Compare five things first. One, how many entry points does each document list. A gap here means one of them did not walk the full perimeter. Two, what material closes them: screwed heavy gauge steel mesh into sound framing is a different job from a bead of sealant and a new screen. Three, is the crawlspace cleanup and insulation replacement included or optional. Four, how many return visits are covered and for how long. Five, what happens if an animal is back inside in six weeks. Then ask about licensing and about what the operator does with each animal caught, and listen for a specific answer. With median home values near $1,300,000, the gap between two bids is small compared with the structure it is protecting, and the cheap bid usually gets there by skipping the exclusion carpentry. Spend the difference on mesh, screws and framing repair. That is the only part of this job that stops the next raccoon from finding the same address.