What is the best spray pesticide to use for spiders on the outside of house and buildings?
Is there a certain chemical to look for when purchasing the pesticide?

Viper, works GREAT!!! I get it from a pest control company.

I use Bifen,kills anything from fire ants to wasps. Safe in the house or outside. I get it on amazon in 3/4 gallon. I mix it 2oz to a gallon of water.

Permethrin. The same thing I use to spray my clothes for ticks, spray the dog for ticks and fleas, spray on every dead critter that comes into my garage.
By the concentrate and mix my own.

The wife and kids don't like the big Orb weavers that show up this time of year. They make huge webs across the windows and door.
I mix up a spray bottle full and go spider hunting after dark. One good misting and they are done. I turn the nozzle to jet for the second story ones.

Just bought a large bottle of the 10% cocentrate at Tractor Supply Friday. Saw a reference to spraying clothes, but no specific dilute instructions. If I wanted to mix up a gallon to spray clothes with, what would be the correct amt of product to add to one gallon of water?

a sneaker

Cy-Kick Safe inside the home too.

Get that or any pesticide at Do My Own Pest Control.

Problem with spiders is that with most pests if you get it on their legs it will kill them, not so much with spiders as you need to get it on the body to do the job right which makes them harder to kill than many other pests.

I have a few thousand you can kill here if you have the time, it's a crazy year for them darn things nothing you can't move/touch without a spider dropping out of anything. Washed my truck the other day and must of flushed out 50 spiders by the time it was over.

I buy 37% Permethrin on amazon, mix it up and spray the foundation, crawlspace, thresh holds, windows, etc 4x a year. I also treat my barns, sheds, and chicken coops with it.

Something I've been meaning to pickup while in town shopping.
We have tons of Brown Recluse and wolf spiders moving in. They know winter is coming.

You want to dilute it to .5% in solution, or at least that is what every commercially available product is diluted to.

So 20 parts water to 1 part of your 10% solution should get you where you need to be. I don't even measure anymore. Just dump a little in the bottom of the spray bottle and top it off with water.

Bengal Gold. There will be insects and spiders laying around dead that you didn't know existed. It's advertised as Roach spray but it kills everything.

tempo works well. thats what we use.

X2

We use it too, get it from tractor supply. Next morning lots of dead spiders around edge of our home. Just rolls em.
Jim

is Tempo over the counter, or do you need a pesticide license?

spiders, we got.

It's OTC at tractor supply and no you don't need a license.
Now it is a little pricey, I think we paid like $56 for a small white bottle. But, its a concentrate and we used a 2-gallon pump sprayer/mixer with hand wand applicator. One bottle if stored in a cool, dry safe place lasts us a couple years and we apply in spring and fall when they seem to be worst around our home.
It seriously rolls every spider I can think of around here. We had a ton of house, wolf, garden, parsons, other species. We applied around soffits, corners, high, low, base, etc. all the way around our house and shed, with a good 2' or more around base of each.
It knocked down everything overnight and into next day. Some of the big dead wolf spiders were impressive size, like 3" to 4" across, and it rolled them up dead as a doornail.
Be sure to wash up thoroughly afterward.
Jim

thanks, Jim!

mostly, we have those house spiders (we call them dust spiders), but we have some wolf spiders, too. never recall them getting as big as yours, but don't want to see them, anyway.

for those opposed to using chemicals...

I read in one of those "country wisdom" books about using spent tomato plants in your basement to repel spiders from your house. when the plants are done in the fall, just pull them up by the roots and hang them up to dry in your basement, and them leave there over winter.

I tried it and it seemed to help. enough that I'll do it again...in ADDITION to adding a chemical component to our solution. (we have a "spidery" house).