Why you need to be careful
Unless proper care is taken, extensions and alterations can damage or adversely affect your home. This could include:
- Damage to the foundations - excavating close to existing foundations can undermine or damage them.
- Damage to drains - excavating close to drains or building over them can cause damage. It is also important that access points, such as rodding points and manholes are not covered over. They are there to allow access for maintenance and to clear blockages.
- Damage to other services, including water and gas pipes and the electrical supply.
- Bridging damp proof courses - damp proof courses are there to prevent dampness. It is important that they are not damaged or bridged.
- Dampness through external walls - the external walls of your home have been designed to keep moisture out. Alterations, including adding insulation into cavity walls can affect their resistance to moisture.
- Structural damage to load-bearing walls, floors and roofs - your home has an integrated load bearing structure and it is important that any alterations or extensions do not adversely affect this structure. It may not be obvious which parts of your home provide structural support to other parts.
- Affecting access - alterations and extensions may make your home less accessible for disabled visitors and less suitable for existing and future occupiers as they grow older.
- Affecting fire safety - your home was built to meet fire regulations and allow you to escape safely if a fire were to occur. Alterations or extensions should take account of this.
- Damaging gas or vapour control membranes - some walls, floors and ceilings have gas tight layers in them to stop gas or moisture vapour. It is important that they are not damaged.
- Damage to separating walls and floors - the walls and floors, which separate you from your neighbours are designed to provide resistance to sound and fire. It is important that any work carried out does not reduce their effectiveness. In England and Wales work on separating walls and floors may be subject to the Party Wall etc. Act.
- Blocking ventilation - there may be ventilation to ground floors, walls and roofs to prevent the build-up of moisture, or to provide combustion air for the safe operation of heating appliances, or to prevent gases building up. It is important that ventilation is not covered over or blocked.
- Covering over or blocking flue terminals - for the safe operation of heating appliances, it is important that flue terminals are not covered over, blocked or modified.
