Hi, thanks for your question. My name's XXXXX XXXXX I'm going to assist you with it.
Unfortunately this can be a difficult question and there is no specific legal provision for determining the ownership/responsibility of a boundary fence.
The first thing to distinguish between boundaries and boundary features. Boundaries are the invisible line separating properties; boundary features include barriers such as fences and walls. With regard to both boundaries and boundary features,it is not unusual for deeds to be silent.
If the deeds do refer to ownership/responsibilities for boundaries, it is common for the deed plan to use T marks along the red boundary line. If these face inwards, it typically indicates that the owner has ownership of the boundary but the wording of the deeds should always be checked to confirm the meaning of the marks. In such cases the deeds may also contain provisions allocating responsibility for boundary features.
However, even if the deeds do contain provisions relating to boundary features, the position may have changed over time. A current fence may have been replaced by two adjoining owners sharing its cost (regardless of the provisions in the deeds).
This means that even armed with information regarding boundary features in the title deeds and from the original owner, the particular circumstances may very well mean that the answers are not be definitive (leaving the matter to be negotiated between adjoining land owners).
You can find some helpful guidance from the Land Registry on the issue of boundary ownership here: http://www.landregistry.gov.uk/public/boundaries
I'm sorry if this is not the answer you were looking for but I hope it assists. Please do let me know if you require any further clarification.