Garage Roofs Built into a Neighbouring Wall
Party Wall Implications when converting the garage into an infill extension. Party Wall Advice
Creating an L-shaped extension is often proposed where a house is semi-detached and there is an existing garage.
In the pictures below we see a typical example. The roof of the garage slopes down to the house to the right and the roof rafters are built into the the neighbour's flank wall (the front door of the garage is visible to the right side of the two photos).
In fact, from a legal perspective, the neighbour's flank wall is not a Party Wall because it is built wholly on the neighbour's own land. Rather, the wall is private to the neighbour, with only the lower section of the wall deemed to be a Party Structure.
We can well assume what works the owner of the house to the left (the Building Owner) wishes to undertake by looking at the existing structure. You may have noticed from the pictures, that internally, the garage roof slopes downwards as it approaches the house to the right. The internal head room is therefore very poor. So any infill extension would naturally involve raising the level of the roof.
As we noted previously, the rafters are built into the neighbour's flank wall. We would be completely right in assuming that the Building Owner does not wish to go to the expense of building a new flank wall alongside his neighbour's flank wall and hence wishes to raise the height of the roof and build the new roof into the neighbour's flank wall. But the question is, does he have the right to do this?
In this post we are going to explore the difference between a Party Wall and a Party Structure and why it matters. The first thing to know about the two is that a Party Wall cannot be anything but a Party Wall to its full height, whereas a Party Structure can be Party only to a limited extent. Lets first look at the difference in definitions between the two.
As we noted previously, the rafters are built into the neighbour's flank wall. We would be completely right in assuming that the Building Owner does not wish to go to the expense of building a new flank wall alongside his neighbour's flank wall and hence wishes to raise the height of the roof and build the new roof into the neighbour's flank wall. But the question is, does he have the right to do this?
In this post we are going to explore the difference between a Party Wall and a Party Structure and why it matters. The first thing to know about the two is that a Party Wall cannot be anything but a Party Wall to its full height, whereas a Party Structure can be Party only to a limited extent. Lets first look at the difference in definitions between the two.
The definition of a Party Wall is one that occupies the land of two owners. A Party Wall is common in the case of the dividing wall between terraced houses where the dividing line is assumed to run down the middle of the thickness of the wall. Hence the actual wall is situated on the lands of both owners. Where there is a Party Wall either neighbour has rights over all of it and hence to its full height and can therefore raise it, enclose on it or cut into it at any point of its height, subject to following Party Wall procedures.
What we have in this case is a garage enclosed on a wall situated solely on the neighbour's land. What makes this wall a Party Structure is that it separates the Building Owner's garage from the Adjoining Owner's house. However, to what height is this a separating wall? Only to the height of the garage roof. In other words, the flank wall above the height of the garage is not a Party Structure. So if I ask, what rights does the Building Owner have over the upper height of the flank wall, you would be quite right in answering 'no rights at all'.
What we have in this case is a garage enclosed on a wall situated solely on the neighbour's land. What makes this wall a Party Structure is that it separates the Building Owner's garage from the Adjoining Owner's house. However, to what height is this a separating wall? Only to the height of the garage roof. In other words, the flank wall above the height of the garage is not a Party Structure. So if I ask, what rights does the Building Owner have over the upper height of the flank wall, you would be quite right in answering 'no rights at all'.
So what does this mean in practise? Could the Building Owner cut into the flank wall to connect a wall to it to the full height of the garage if he wants to say, create a dividing wall between the front and rear of the garage? The answer is 'yes', he can do that subject to following the Party Wall Act procedures of serving Notice etc. On the other hand, can the Building Owner remove the roof and fix it to the flank wall at a higher level? No, there is no Party Wall procedure for doing that as the Act does not allow this.
So what will the Building Owner need to do? He will need to construct his own flank wall alongside his neighbour's wall in order to support the new raised height of the roof. This will usually require sequencing of the foundations so as not to damage the neighbour house's foundations.
A possible solution would be to keep the current roof in place and instead reduce the floor level. But if step-free access is required, is unlikely to be a suitable alternative.
Unfortunately for the Building Owner, he hired an architect who did not understand the Party Wall Act and hence the drawings incorrectly showed the proposed work as raising the roof by inserting the rafters into the flank wall at a higher level. To save headache and costs always go with an architect who does understand Party Wall matters. Or ask me to recommend you an architect.
BH Party Wall Surveyors is a London-based party wall surveying company with offices in London and in High Wycombe, offering advice and party wall services to building owners and adjoining owners. Readers should always take their own professional advice and not rely on the information provided here particularly given that no two situations are identical.
bh@bhpwsurveyors.co.uk
www.bhpwsurveyors.co.uk
