The common and German wasps are the most common wasp pests throughout the UK and Northern Europe, they are between 10 and 20 millimetres in length, have distinctive bright yellow and black banding and have two pairs of membranous wings.
Wasps pose a threat when they nest in close proximity to humans. Nests are frequently found in lofts spaces, cavity walls, behind structural cladding and in flowerbeds. Wasps primarily feed on insects which they feed to their young, but later in the season as larval production slows they tend to be attracted to sweet substances and can become a significant nuisance in homes, kitchens, bakeries etc. 

When wasps perceive a threat, to themselves or to their nest, they attack by inflicting a painful sting, and unlike bees can sting multiple times. While one sting may be no more than unpleasant, multiple stings to sensitive areas such as then head, face or inside the mouth can be much more serious. In rare cases even a single sting can induce a condition called anaphylactic shock, which is an extreme reaction to the toxins in the wasps venom. This condition, without instant medical attention, can cause death in a very short time.
Late in the season, with the onset of cooler weather and the with ingestion of fermenting, over-ripe fruit wasps can become more irritable and the chances that they sting becomes more likely.
Wasps construct their nests from paper, produced by chewing wood. If they chew into the beams of your roof, or the wood in your walls, this could result in structural damage.
What action can be taken?
While insecticides are commercially available, we would strongly advocate calling in professional pest controllers. Some of the most effective pesticides cause wasps to become over excited and pest controllers will have access to the correct personal protective equipment. Applying pesticides without this equipment would put you in significant danger of receiving a possibly dangerous number of stings. Contact Pest-A-Lance for a free, no obligations survey.
Other types of wasp:

Larger, rarer and less aggressive than common and german wasps, most commonly found in southern England and throughout Europe. Due to it’s rarity and less aggressive nature, we would suggest that hornets should not be destroyed unless they are in or close to your home. 
Tree Wasp and Norwegian Wasp

Slightly smaller than their common and german cousins, these wasps are known for their aggression, but also for their avoidance of humans and building. It is rare to find this species of wasp nesting or entering building, preferring trees and bushes, but where they do enter buildings it is very important to call in professionals with the proper equipment to deal with them.
Giant Wood Wasp

A fearsome looking but quite harmless species of wasp, 5cm long with shiny black and yellow banding, distinguishable from other wasp and bee species by it’s lack of a “wasp waist”. Instead of a sting it has an egg layer which it uses to lay eggs inside freshly felled trees where the grub takes up to three years to develop, this means that now and then adult wood wasps will emerge from wood used in construction of houses, usually within a year or so of completion.
Something to consider:
Wasps do have their uses such as killing garden pests and pollinating flowers. Where a nest is located far from homes and thoroughfares we would advocate the consideration that no action should be taken.