Do semi detached houses need a fire wall on both properties

Not sure if you are referring to the loft? Terraced and semi detached houses built before 1930 would often have continous lofts if the roof structure did not require the support of a dividing wall. Where it is not illegal to have no dividing wall its obviously very dangerous and would be picked up on survey. Since the 1930's it would be a requirement.

The lack of firewall will be picked up by some surveys and some lenders will want that work done.. One firewall is required.. between the houses .. if your doing a loft conversion as it just makes sense to be safe.. We have noticed most houses even if made in the 1950’s won’t have a firewall hence we also do this as part of the loft conversion.

Party walls and fire barriers in roofs When you are living in a terraced or semi-detached house, at least one of your walls is connected to your neighbour’s. This is termed a party wall and can be a bone of contention if you don’t get on well with your neighbour. You will also likely have a fire wall in your loft that protects you against fires from adjacent properties. Party walls and fire barriers in roofs separate terraced or semi-detached homes from each other to prevent house fires from moving from one home to the next. When it comes to party walls and fire barriers in roofs, you need to ensure your home is up to building regulations for safety and legal reasons. Having a fire wall or fire barrier will also mean your home doesn’t completely collapse during a house fire, helping you to escape. Many older terrace homes do not have firewalls as they were often built cheaply to substandard quality. This may flag up issues with your mortgage lender, and they may insist your property.