With insurance policies you have a choice of cover for buildings and your contents within the home. Standard cover, or standard cover with optional accidental damage extension, which typically costs an extra 10-15% to include. You may decide to have standard cover on both, or accidental damage on buildings, but not on contents, or visa versa.

Firstly we will detail what is insured under the standard cover which you will get automatically, then give an example of the sort of protection the accidental damage extension gives you if selected:

Standard cover for buildings

Loss or damage caused by fire, lightning, explosion, earthquake, smoke, storm or flood, escape of water or oil from any interior fixed heating or domestic water installation, washing machine, dishwasher, refrigerator or freezer, damage to any fixed heating or domestic water installation caused by freezing or forcible and violent bursting, theft or attempted theft, riot, strike, labour or political disturbance or civil commotion, malicious persons or vandals (excluding damage caused by any person lawfully in the home), subsidence, ground heave or landslip, collision involving aircraft, aerial devices or anything dropped from them, vehicles or animals, falling trees, branches, satellite dishes, receiving aerials and their fittings and masts.
There is an element of accidental damage under the standard cover: Accidental breakage of fixed glass, ceramic hobs and sanitary ware and accidental damage to underground services, septic tanks and drain inspection covers to the home.

Accidental Damage extension for buildings

This covers mishaps such as a nail going into a water or gas pipe when putting up a picture.

Standard cover for contents

Loss or damage caused by fire, lightning, explosion, earthquake, smoke, storm or flood, escape of water or oil from any interior fixed heating or domestic water installation, washing machine, dishwasher, refrigerator or freezer, theft or attempted theft, riot, strike, labour or political disturbance or civil commotion, malicious persons or vandals (excluding damage caused by any person lawfully in the home), subsidence, ground heave or landslip, collision involving aircraft, aerial devices or anything dropped from them, vehicles or animals, falling trees, branches, satellite dishes, receiving aerials and their fittings and masts.
There is an element of accidental damage under the standard cover: Accidental breakage of mirrors, glass tops, ceramic hobs and fixed glass in furniture, television, audio, video and computer equipment, satellite dishes, CCTV cameras, receiving aerials and their fittings and masts.

Accidental Damage extension for contents

This covers accidents, such as spilling wine on the carpet or dropping an ornament.

As you can see you do get some accidental damage under standard cover for contents as detailed above, but if fuller insurance is required then the extension must be included.

Accidental Damage cover does not insure wear and tear. Most things have a useful lifespan, so when it wears out or stops functioning through use you cannot claim under a home insurance policy, as it is not a warranty. Damage caused by pets and accidental damage to items taken outside your home are also not insured.