Ants coming up thru the floor?

Simple solution would be to glue and screw plywood to the planks. To kill the ants you would need to go underneath and heavily spray hoping you get any ant hills.

Ants invade a porch for three reasons: there is food there, it is a path to food or it is near their colony.

Sweep the porch and remove anything portable that's attracting the ants, such as a garbage can.

Place ant baits near the colony or on the porch. The ants will carry the poison into the colony and kill off the population.

Follow the ant trail to find the path they're using to invade the porch. Sprinkle black or cayenne pepper along the path. Also, sprinkle the black or cayenne pepper around the perimeter of the porch and on the ground surrounding the porch. Pepper agitates ants' senses, so they stay away from it.

Spray glass cleaner on ants when you see them on the porch; this will instantly kill them.

https://www.hometalk.com/diy/outdoor/pest-repeller/cheap-easy-homemade-ant-spray-31195184

If you have sprayed and they are still coming in, I would recommend a professional pest control guy. They have stronger chemicals. The other issue is the floor. How big are the gaps they are coming through. If they are not to big you could try and seal the gaps.

When we have ants coming in it is the worker ants looking for food, this happens every year about this time. We set up ant bait called Terro (available in diy stores) on small pieces of cardboard, the coated non-porous type. Place it in their parades or where you see some entering.The Terro box gives you some squares, but you can easily make your own. The ants take this back to the colony and it kills the colony.

Another thing you can do is dust where they crawl with DE (diamateous earth), be sure to get the food grade, also at diy stores. This destroys their exoskeleton.

Sprinkle cinnamon where they are coming it works a treat.

Ants will find the tiniest crack to make their way in if there's food. Usually there is a source that needs to be eliminated. We've been able to keep them out with cornmeal. I didn't think it would work, but it's magic. https://www.hometalk.com/diy/outdoor/pest-repeller/cornmeal-the-easiest-way-to-get-rid-of-ants-8370211

This is the best stuff on the market. A few dots in the path of the ants and they carry it back to the colony where it will kill the queen. If you use topical sprays it only kills the worker ants and the queen will just make more. You can get it on Amazon.

Optigard Ant Bait Gel offers unparalleled control of a broad spectrum of ants, including Argentine, carpenter, ghost , and other nuisance ant species, by ingestion and transfer of the bait, providing efficacy against the entire colony, not just the workers. Optigard can be used for both clean-out and maintenance.

I seem to remember my mom using borax. Here is a post I found about it. https://www.mashupmom.com/yes-borax-got-rid-of-the-ants/#:~:text=Mix%201%2F2%20C%20sugar,it%20back%20to%20their%20home.

Hi Peggy - Those little buggers are relentless, aren't they?!? This is the most effective method and all-natural spray DIY that we use with ants. It's best indoors, but will also work outside with more frequent applications. It's even been featured on Hometalk! Hope this helps! Hugs, Holly

https://pinkfortitude.com/ant-spray/

PS - We have a FREE eBook with recipes for all of my homemade and all-natural cleaners. You can download it here --> https://pinkfortitude.com/thank#GreenClean

We live on a small lake and we have ants in all sizes that come onto the deck, screened in porch and house. I have found that Ortho Home Defense is the safest and best spray for ants. I use it all the time and it kills them instantly - follow instructions on the back and spray under the porch and on the porch and your ant problem will be solved. You can buy this at Home depot, Walmart, etc

You will have to spray every year but 2 years ago my husband had a bad batch of wine that turned to vinager so I told him to dump it around the whole foundation for bugs we have not seen a ant in 2 years and we had them coming in the house carpenter ants tini ants Not one this year eather this is year 3. So use white vinager spray a healthy amount all around the house and all under the deck

I’m sorry the doller store has large bottles of vinager for cleaning try that

I would spread diatomaceous earth underneath and around the edges of the floor. Sevin granules are good on mounds as well. Both of these products would be fine around eating areas as they have little to no scent. Diatomaceous earth is safe and is still effective if it gets wet, as long as it isn't washed away. It would be my first choice.

Hello. I highly recommend the commercial products made by Terro. If you look over at the reviews and QA on Amazon and see how highly rated the traps are.

I have been using them both indoors and outdoors - and been very successful in my overall situation. Additionally- I sometimes do an exterior Home defense foundation perimeter type product as well for spiders. Hope this helps.

We have ants galore, as we live in the woods. Advion ant gel works absolute wonders at eradicating them! You just need a tiny bit wherever you see them coming in.

I use: 2 c distilled vinegar, 2 c water, 3 TBS. Dawn, 3 TBS salt and mix it all together and put in spray bottle. Good luck!