Party Wall Act

Under the Party Wall Act (1996) which applies in England and Wales, the written consent of the owners of a neighbouring house must be received before some projects can begin. The Act relates to the construction and repair of walls on the line of the junction, as well as any adjacent excavation and construction. Consider taking the advice of a surveyor with experience of this legislation.

This letter is suggested for a typical loft conversion:

Dear ...,

For some time now we have contemplated a loft conversion and have now decided to go ahead with such a project.

Apart from some initial noise which will be restricted to the working day, the only potential effect to your property is in the Loft area itself where, when work commences, two or three steel beams (RSJ's) are inserted into the party wall between our two properties.

This work takes place entirely on our side of the wall and entails removing a few bricks from our side and fitting a short steel plate (about 18" long) onto which the RSJ sits.

The entire process takes no more than two or three hours.

The project will be completed strictly in accordance with Building Regulations and monitored by the Local Authority Building Control Officer.

In the unlikely event that any damage should occur to your property as a result of this conversion, we accept full responsibility for any remedial work.

We shall be grateful if you would sign a copy of this letter confirming that you have no objection to this project.

Please let us know if you require further information or have any unanswered questions.

Yours sincerely




For more detail on the Party Wall Act, we are delighted to publish this article by Justin Burns of Peter Barry Party Wall Surveyors

The Party Wall Act & Period Properties

The foundations upon which residential properties are built have increased in depth significantly over the last 150 years. It was not unusual for Victorian houses to be built upon no more than a footing of corbelled brickwork. By the 1930s the corbelled brickwork was being built off a base of tightly compacted gravel. Compare this to the mass concrete foundations that are used on even the smallest single storey extension today and you will understand why owners of period houses get concerned when someone wants to dig a large hole next to their property.

You may ask what this has to do with the Party Wall etc. Act 1996. Well, the clue is in the full name of the Act, the 'etc.' is there for a reason. It is in there to cover adjacent excavations. Section 6 of the Act states that a Building Owner proposing to excavate within three metres of their neighbour’s property and to a depth greater than the base of their foundations must serve a Party Wall Notice upon their neighbour. Because the depths of foundations have increased over the years, new building work close to a period property will almost always be notifiable.

Impact of Vibration on Party Walls

Of course the Act is also relevant to work on shared walls, and there are additional concerns here as well for owners of period properties. Walls in Edwardian and Victorian properties were built with lime mortar as opposed to our  modern cement based equivalent. While lime mortar has many desirable qualities, it does not react well to vibration. Vibration causes lime mortar to break down and weaken. Although lime mortar is quite accommodating of movement as the lime dissolves and fills cracks, the problem with vibration is that it causes the outer edges of the lime mortar joints to break down so while the middle section of the joint will heal the outer edges may have already fallen away. This is particularly true in the loft and to the sub-floor area where there is no layer of plaster to hold the joint in place. This can also cause a secondary problem where the dislodged lime mortar reforms in the gaps between the sub floor timbers and the walls bridging the damp proof course.

Removal of Chimney Breasts

The removal of chimney breasts from a party wall and the insertion of beams and padstones in to a party wall are both tasks that are covered by the Act but also tasks that cause considerable vibration to mortar joints. A Party Wall Surveyor should recognise the risk and put a clause in the Party Wall Agreement prohibiting the use of vibrating breakers for such tasks. Doing the job with a hammer and bolster may take longer but it will preserve the integrity of the brickwork.

Damp-Proofing and Party Walls

Period properties are increasingly the subject of works which are notifiable under the Act even though those works are, more often than not, unnecessary. The default remedy to damp problems proposed by fee-driven damp-proofing companies is the injection of a supplementary damp-proof course. This involves the drilling of a series of holes into which chemicals are pumped. Where this work is to be carried out on a shared wall a Party Structure Notice must be served.


Insurers under pressure from home owners are increasingly authorising the underpinning of period properties as a remedy for minor subsidence. Underpinning requires excavation and where that excavation is within three metres of a neighbour’s property a Notice of Adjacent Excavation must be served.

Receiving a Party Wall Notice

Finally what should you do if you receive a Party Wall Notice from your neighbour? You have 14 days from the date of the notice in which to consent. If you choose to consent, the work can commence immediately and there will be no Party Wall Agreement. If you do not reply to the notice you are deemed to have dissented under the Act and must appoint a surveyor. You can also indicate your dissent on the notice’s acknowledgment.

If the Building Owner has suggested a surveyor on their notice you may concur in the appointment of that surveyor as ‘Agreed’. Equally you may appoint a surveyor of your choice. Under all normal circumstances the surveyors’ fees are paid by the Building Owner.

Once surveyors are appointed they will produce a Party Wall Agreement known as an ‘Award’ which sets out the rights and responsibilities of the respective owners. Once the Award is agreed it is served on the two owners and work can commence although there is a fourteen day appeal period.

Article by Justin Burns BSc MRICS of Peter Barry Surveyors

Peter Barry have a tool which produces party wall notices for homeowners - The notices produced are in line with those suggested in the Government Explanatory Booklet. If the user follows the simple instructions they will generate a valid notice and acknowledgment which can be printed off and sent to their neighbour.

Peter Barry also have a website where we take homeowners party wall related queries and publish the answers on the site. Approximately 70 questions have been answered to date and published on