It happens every September. You're watching the telly at half ten and a large one legs it across the carpet. If you're looking for how to keep spiders out of the house, start with the reason they turn up now: it isn't the cold. Early autumn is mating season for the house spiders we live with all year, and the males leave their webs to go looking for a female. Walking across the floor is what makes them visible. They were already here in July — you just couldn't see them.
That changes the job. It isn't about stopping them coming in from the garden. It's about making the house less comfortable and shutting the routes the outdoor ones actually use.
How to keep spiders out of the house: seal the gaps first
Give it one evening and walk the perimeter of the house:
- Under the doors. A brush strip or draught excluder on the front door and on the back or utility door. If light gets through, a spider gets through — and you'll feel the difference on your heating bill too.
- Pipe and cable entries. The hole around the waste pipe under the sink, where the broadband cable comes in, the extractor outlet. Five minutes with a tube of sealant or expanding foam.
- Window frames and trickle vents. Check perished seals and, if you have them, the gap above roller shutter boxes — that's usually the front door as far as insects are concerned.
- Airbricks. Never block them, you need the ventilation. Fit fine mesh on the inside instead.
Take away what they're eating
Spiders stay where the hunting is good. Midges and moths indoors mean spiders indoors. The porch light pulls insects to your back door every evening and they follow, so swap it for a warm or amber bulb, or move it away from the doorway. Inside, draw the curtains at dusk so the light doesn't spill out of the glass. Fly screens on the windows you leave open are worth every penny in summer, and they still earn their keep in September.
Make the quiet corners less appealing
Webs go up where nothing disturbs them: behind the sofa, along the coving, in the garage, under the stairs, in the shed. Run the vacuum over those spots once a week through September, ceiling corners included, and take down any egg sacs — pale silk balls the size of a pea. A web that gets wrecked every few days gets abandoned. Tidying helps as much as cleaning: sealed plastic boxes instead of stacked cardboard, and firewood, plant pots and wheelie bins kept away from the back door rather than propped against it.
Conkers, peppermint and the rest of the folklore
Putting conkers in the corners of the room is a lovely story with no evidence behind it whatsoever. Peppermint and eucalyptus oil sprays have a bit more support from lab work, but the effect is weak, wears off within days and needs constant reapplying — fine as a finishing touch, useless as a plan. Plug-in ultrasonic repellers have never been shown to work. And insecticide sprays aren't worth it either: they kill the spider already in the room, do nothing about the next one, and your family breathes them.
Getting one out without hurting it
A glass and a piece of card. Put the glass over it, slide the card underneath, and release it in the garage, the shed or the porch — not the far end of the garden. A house spider won't survive outdoors and will simply try to get back in. If you genuinely can't face it, keep a long-handled spider catcher by the stairs and you never have to get close. For what it's worth, nothing you'll find indoors in Ireland or the UK is dangerous. False widows are established in places and can bite, but it's uncommon and usually no worse than a wasp sting.
Seal the gaps, change the outside light and run the vacuum along the skirting boards, and you'll notice the difference inside a fortnight. If you're getting the house ready for autumn anyway, have a look through our home range.