There are spiders that will forage in the garden like the Wolf Spider and the Huntsman. These spiders won’t have webs, but will eat insects as they find them. Wet weather will often bring them into the house. They are scary looking for most people and the Huntsman moves rather quickly when disturbed, often catching unsuspecting people by surprise. Huntsman have been known to jump short distances which also adds to the surprise factor.
Webbing spiders will be found around the outside of the house at the guttering, eves, weep holes in bricks, hot water systems, steps/stairs, playground equipment and toys. Inside you will generally find webs at the cornice or around the corners of rooms and down lights.
Generally, the spiders found in the corners of rooms up high will be Daddy Longlegs and other webs at the cornice belong to an equally harmless but messy house mate. Redback spiders, a particularly nasty critter should you find yourself bitten, may be found hanging from downlights and under furniture. The Daddy Longlegs is well known for doing battle with the Redback and winning most of the time; so, don’t be too harsh on the Daddy Longlegs.
The treatment of spiders will generally need to be direct chemical contact. Spiders don’t have veins in their legs and therefore won’t absorb chemical by walking over it. They don’t clean their feet like a cockroach, so the chemical is not ingested. If they sit on the chemical residual for any length of time, you may find them shrivelled up against a wall or corner. The Wolf spider and the Huntsman may fall foul to chemical residual on the floor, but all webbing spiders will need direct contact with chemical. Some chemicals allow for crystallisation in the web, which in turn comes into contact with the body of the spider and kills it.
Some companies may offer an unrealistic warranty on pests in order to get your business, and the warranty may or may not be honoured. Do not be surprised if they take a month or two before they can get back to re-servicing the spiders, if they come back at all. If you understand how the chemical works with the spider, you will understand what is reasonable. Three months is the general warranty for spider control. (webbing spiders only)