The complete guide
Raccoon and Cat Deterrent Spikes, A Practical Buyer's Guide
The problem with a favorite fence
Most animal problems in a garden are really route problems. A cat does not sit on your fence because it likes your fence. It sits there because the fence connects two places it wants to be, and the top rail happens to be flat and comfortable. A raccoon behaves the same way. It finds the route with the best grip and the fewest obstacles, uses it once, then uses it every night after that.
That is why sprays, scent granules and noise devices often disappoint. They either wash away, run out, or stop registering as a threat after a week or two. Animals are quick learners, and anything that never actually changes their experience of the surface gets ignored.
Physical deterrents work differently. They change the surface itself. A fence top with spike strips along it is simply not a good place to stand, and no amount of habit makes it one. That is the logic behind the best anti climb fence spikes, and it is why they keep working long after a spray bottle is empty.
How these spikes work
Each strip in this pack is a run of plastic points on a narrow base, about 11.22 inches long, 1.57 inches wide and 1.57 inches high. The points sit close enough together that a paw cannot find a flat place to rest, and the whole strip is low enough that it does not turn a garden fence into something that looks like a prison wall.
There are two effects at play. The first is visual. An animal approaching a ledge can see the surface is broken up and often just picks another path before touching it. The second is physical. If the animal does try, the footing is unstable and uncomfortable, so it backs off. Neither effect relies on injury. The point is to make the surface unattractive, not to punish the animal.
This is also why the same strips get used against birds. Pigeons looking for a ledge to roost on have exactly the same problem as a cat looking for a fence rail, which is why plastic bird spikes and cat deterrent strips are essentially the same product in different packaging.
Where they go
The honest answer is anywhere flat and narrow that something keeps standing on. In practice, the most common spots are:
Fence tops and capping rails, which is the classic use. Garden walls, especially brick walls with a flat course that lines up with a neighboring roof. Shed roof edges and ridges. Gutter lips and flashing where pigeons settle. Window sills and ledges on the exterior of a house. Balcony railings and the top rail of metal fencing.
The one rule that matters more than any other is continuity. A run of spikes with a two-foot bare section in the middle is just a run of spikes with a doorway. Cats in particular will find that gap on the first night. Plan the full length you need before you start fixing anything.
Fixing them properly
The strips can be cut, which is the feature that saves most installations. Real fences have posts, brackets, downpipes and corners. Being able to trim a strip to 7 inches so it fits neatly beside a post means you get full coverage instead of a compromise.
Choose the fixing to suit the surface. On timber, screws or nails are the most secure, and pre-drilling stops old wood from splitting. On brick, render or concrete, outdoor construction adhesive works well as long as the surface is clean and dry before you start. On smooth painted metal or tile, heavy-duty exterior double-sided tape is a reasonable no-drill option. On rails, pipes and mesh, UV-stable zip ties are usually fastest and neatest.
A few things worth knowing before you commit. Adhesive needs dry weather and some cure time, so check the forecast. Tape struggles on dusty or chalky surfaces, so wipe the area first. Zip ties are the component most likely to need replacing after a few years in strong sun, which is a small job, but worth putting on the list.
Who they suit
These strips suit anyone with a boundary problem that keeps repeating. Gardeners who are tired of finding dug-up beds and paw prints in the soft soil. Homeowners who can hear something crossing the shed roof at two in the morning. People whose bins keep getting worked over by a raccoon that arrives via the fence line. Anyone with a balcony that pigeons have decided is now theirs.
They also suit people who want a solution they do not have to think about. There is nothing to charge, refill or reset. Once it is fitted, it is doing its job every night whether you remember it or not.
They are less suited to a few situations. If you have small children who play right against a low wall, do not fit spikes at child height. If your problem animal is getting in under the fence rather than over it, spikes on top will not help and you need to fix the gap instead. And if your fence top is broad and flat, you may need two parallel rows rather than one, which changes how many strips you should order.
Choosing the right quantity
Work out the length you need to cover first. Each strip is roughly 28.5 cm, so three and a half strips make up a meter in a single row. A 20 pack covers a bit over five and a half meters in one row. Double that up for wider surfaces and the coverage halves.
Measure the actual run an animal uses, not the whole boundary. Most of the time there are one or two preferred crossing points rather than a free-for-all along the whole fence. A few evenings of watching, or a look at where the moss is worn off the top rail, usually tells you exactly where to concentrate.
Buy slightly more than your measurement suggests. Offcuts, awkward corners and that one extra ledge you had not thought about will eat into the pack faster than you expect.
Looking after them
Maintenance is light. Rinse the strips with plain water and a soft brush when dust, leaves or droppings build up between the points. Skip solvents and strong cleaning chemicals, which can make plastic brittle over the long run.
Check the fixings a couple of times a year, and always after a bad storm. Screws loosen, adhesive edges lift, and zip ties stretch. A quick walk along the fence with a screwdriver takes five minutes and keeps the barrier doing its job.
Also keep the area behind the strips clear. If leaves pile up against a run on a gutter or a flat roof edge, water sits where it should not, and that causes more trouble than the animals ever did.
The short version
These are 20 black plastic spike strips, each about 11.22 inches long, meant for fence tops, walls, ledges, gutters and railings. They are cuttable, so they fit real surfaces rather than ideal ones. They fix with screws, nails, adhesive, outdoor tape or zip ties, and plastic means no rust stains on paintwork.
They work by taking away comfortable footing, which is the one thing cats, raccoons and roosting birds all need. Cover the full run with no gaps, fix them firmly, check them once or twice a year, and the problem route stops being a route.