There are two main ways of looking at house defence: how to stop wasps getting into your house, and how to keep them away from the house. You need to be aware of wasps in your loft but that is not covered in this website. I don't think there is an easy way to prevent it. I am interested here in the event that can affect us many times a day right across the whole of the summer on warm dry days. That is wasps coming through open doors and windows. 

Unlike Hitchcock's film "The Birds" there are not many wasps outside your house seeking entry via every pore. The wasps are at doors and windows because of smells. The solution is to keep access closed, especially while you are cooking. It is also important that you keep smells away from your doors. Moving the dustbin away from the back door is helpful. Ensure the lid is always closed. Pet food remains can attract wasps.

There are other solutions. You can try to create a through draught by opening windows where there are no food smells attracting wasps. The en suite bathroom and one other bedroom might suffice. In the autumn this leads to queen wasps seeking shelter for the winter. Just such an over wintering lodger stung me on the foot in my bedroom one April. For this reason I urge caution during Spring Cleaning.

Alternatively create a distraction using wasp traps.

You can make your own (there are commercial wasp traps on the web) with a 200g coffee jar, or similar, with a lid and a central hole (foil or other) containing sweet smelling liquid contents up to about one third level. Use jam, beer, fruit, orange juice and a little water. I have four of these placed around the outside of the house. One is placed on the windowsill near each window that I open regularly during food preparation and another is placed near the back door. The untrained eye might assume that I'm attracting wasps. It is simply trapping them and funnelling them away from my kitchen. It is rare for anything other than wasps (and a few flies) to enter the trap. Reduce the smells emerging from your house by keeping most of your fruit in the fridge. One web site suggests wasps may sit on moist washing. I have no experience of a wasp doing this but am now more cautious grabbing the washing off the line in case of a sting to the hand!