The part/ The owner parts of the property in which construction work is to be carried out. There are a number of things you can only do on a party wall after getting a written agreement from a neighbor, which means that the price is generally not applied retroactively. If work begins without consent, it is a matter of managing the potential consequences, i.e. damage to the adjacent land. If this cannot be agreed between the neighbours, it must be brought to justice. The 14-day period covered by Section 5 of the Act is the period during which the adjacent owner must give consent. If they do not agree before the end of the 14-day period, they must appoint a party surveyor. If they are unresored after another recall, the contractor must name someone on their behalf. The official law does not refer to these distinctions or opinions. There are cases where the work was granted retroactively, but it depended on the auditor`s opinion if he felt that the authorization was in a position (which is not the case in the event of injury). If a neighbour has already completed the part of his work, it is a matter of dealing with the possible consequences if the property of the adjacent owner has suffered damage. However, if the neighbours fail to reach an agreement, the case will have to escalate and be tried. Source www.gov.uk/party-walls-building-works/work-tell-your-neighbour-about Thinkers have long assumed that the Louis/Sadiq case  EWCA Civ 935 was the authority for the thesis that there is no jurisdiction for retroactive awards, that is, for work done prior to awarding or prescribing a prize.
This has always been a false assumption, as has been confirmed in another case: Rodrigues v Sokal  EWHC 2005 (TCC). If they were to build a similar expansion in the future, they would have the right to cut off the part of their neighbour`s foundations that the project plans to make, subject to further notification. In this kind of situation, it is better for the neighbours to agree to build a single wall that crossed the border and use it as a party wall between enlargements – even if it is easier said than done.