Loft Extension on Party Wall
Raised Party Wall


If the notice is served to cover a development or extension all the Adjoining Owner's reasonable costs should be met by the person undertaking the work. You must ensure that your surveyor's fees are reasonable as the person doing the work will not be expected to pay excessive or unreasonable fees and in that circumstance some  surveyors have been known to try and obtain the difference from their appointing owner. If you agree to a surveyors Terms & Conditions be sure that you understand possible liabilities.

If the notice is to repair defects to a shared wall or structure fees and costs are apportioned according to responsibility for the defect & the use of the said wall.  See the section on Adjoining Owners fees in our Terms & Conditions


It is generally a good idea to have a single Agreed Surveyor. There should not be any 'conflict of interests' as Party Wall Surveyors have  a strict duty to be unbiased and fair.

A problem  may arise is if the Agreed Surveyor also has another duty within the construction team (i.e if he or she is also the Architect, Engineer or Project Manager). This should be avoided.

Contact us for FREE ADVICE either using the link or by phone (020 8788 7128) or e-mail.​

I live in a flat over proposed Works - How might i be affected?

If your neighbour below is removing load bearing walls that support your floor or excavating deeper than your foundations the work falls under the Act. 

The most common example of this is where the owner of a ground floor flat in a normal “L” shaped terrace removes the side and rear walls of the back addition to create a large open living space with a side infill and rear extension.  This involves temporarily supporting the building  above, demolishing the existing walls then transferring the load onto new beams.

​When this type of work is undertaken great care is necessary to control the methodology to minimise the risk of any movement occurring during the transferal of load onto the new structure as any slight settlement can cause damage to the flat above.

my neighbour is digging a new BasemenT -   will this Affect Me?

Basements inherently involve the greatest risk of causing the most severe type of damage and the risk is most acute if the buildings are attached (as in a terrace or semi-detached pair) and if the work involves the underpinning of the Party Wall. 

Whilst it is of course essential that this type of work is properly designed by a Structural Engineer, the principle risk of damage arises from the execution of the building work as only a small amount of movement can cause extensive and costly structural and decorative damage.

It is essential that this type of work is carried out by a skilled and experience operative and who are properly supervised and in accordance with methodology agreed by an Engineer. Where this type of work is proposed an appointed Party Wall Surveyor will ensure that all necessary precautions are required to minimise the risk of problems arising from the works


Is loss of daylight or Views covered?

If your neighbour proposes to build an extension you may be concerned at the over- shadowing effect and loss of daylight or a view. These are not matters that are controllable under the Party Wall Act but are matters that may be considered by the local authority when granting planning permission. In some there may be a 'Right of Light'which can be enforced.

Should i agree to a party wall?

New walls built along boundaries can either be built wholly on the property of the person undertaking the work, or by agreement the wall can be built as a Party Wall astride the boundary. In this case the wall will normally project about 105mm (4 in) over the boundary.

​It is often  a good idea to agree to a Party Wall as only small ribbon of land is sacrificed but you would then have the right to use the wall that is built and you would also have some control over to the height and finish of the wall. Even if you do not plan an extension a Party Wall may suit future owners and save them expense. This may make your property more attractive to a potential purchaser.

If space is restricted and you have no intention ever to use the wall it then it should be built wholly of the property of the Building Owner. 



With side or rear extensions damage can be caused by the excavation required for foundations if this excavation is deep and close to the foundations of a neighbour’s building so excavation must be executed with care or in accordance with an approved methodology to minimise the risk of undermining the foundations of the neighbours building.

With rear and side extensions access is often required onto neighbouring land to build. The Act gives a person doing such work a right of access in some  circumstances but if  right is exercised precautions must be  taken to protect  a neighbour's property. These  precautions would should be included in any  Party Wall Award.


Lofts  normally involve cutting into the party wall for beams. This can damage the wall and there are also additional loads imposed.  Some loft extensions are dormers set away from the party wall. Others involve raising the Party Wall itself to maximise internal area. Both of these are satisfactory solutions. 

A ‘compromise’ that is sometimes proposed to save costs or to avoid planning control is to build a large ‘box dormer’ with a tiled lightweight wall on the Party Wall parapet. This can give rise to problems as rainwater is diverted onto the neighbor’s roof and it  also makes it difficult for the neighbour to later build  a full width loft extension. We try to discourage this type of loft conversion.

 Frequently Asked Questions: 


If your neighbour appears to be starting relavant work without notice you should first contact your neighbour in case your neighbour is unaware of the need to serve notice. If works are continued without a notice being served the person doing the work is breaking the law and you will lose much of the protection that you are entitled to receive under the Party Wall Act.  In this case you should consult, in the first instance, a Party Wall Surveyor. We will be pleased to advise you.  

If a person undertaking work refuses to issue a notice and continues to undertake works then you may need to take legal advice. In most cases a court injunction can be obtained to stop the works. This is of course a last resort and should be avoided if at all possible.


As long as a notice is served you are protected by the Act. It is best that you decide how to respond within the 14 day period given. If the work is relatively minor then you can consent subject to a prior schedule of condition of your property.   Otherwise you can dissent and have a Party Wall Award. Contact us and we can advise you based on the circumstances.

If you do not respond for 14 days and then for 10 days after a further reminder notice is served then the person doing the work can appoint a surveyor for you.



If your neighbour has served you with a notice you must either consent or dissent. Many surveyors advise owners to dissent and appoint them to make an Award but this is not necessary to have the protection given by the Act. If the works are simple (i.e a domestic loft or rear/side extension not involving deep adjacent excavation close to your building or underpinning of your building) then you will have all the protection of the Act if you consent subject to a prior Schedule of Condition of your property which should be made by a professional surveyor.  In these cases we bind the notice, consent schedule of condition and relevant drawings together with explanatory preambles as a single document. Click here for more information

If a problem or dispute arises during works, and if this cannot be resolved between the parties  then a Surveyor or two Surveyors can still be appointed to make an Award, 

The principle effective difference between a Agreement (including a Schedule of Condition) and an Award is that with an Award the surveyor will normally make a final inspection. This may be a consideration if you live remote from the property of if you would just prefer a Surveyor to inspect. Please contact us for further advice.

Whether you decide to consent or dissent surveyors fees would normally be paid in full by the person undertaking the work (see note on this page)

The Party Wall Act etc. Act 1996 gives people wanting to do work to their properties specific rights (for example a right of access onto adjoining land) and it also gives neighbours a say  over how the rights are exercised and protection against damage or adverse effects.  The person doing  the work must first serve a notice on affected neighbours. If a neighbour consents the works can progress, otherwise  a Party Wall Award must be made. In either case neighbours receive the protection of the Act.

​​Watson Woods SURVEYORS

Party Wall Surveyors

C​ontact us for FREE ADVICE either using the link or by phone (020 8788 7128) or e-mail.​


Will Internal Works & Removing chimney breasts affect me?

Internal work such as removing certain internal walls, inserting beams and cutting away chimney breasts are covered by the Act and require notice because they have the potential to cause damage to neighbouring properties. Internal floors or walls a can contribute to the stability of a Party Wall so their removal must be considered carefully.  The removal of chimney breasts is particularly important as this gives rise to a number of considerations:-

  • The remaining wall behind a removed stack may need to be upgraded to  provide necessary resistance to noise and fire.
  • If a chimney breast is removed any stack above must be properly supported or the Party Wall may be eccentrically loaded which can cause damage.
  • If there are  flues on the neighbour’s side these may  be damaged mechanically or by vibration. The flue lining can fail and flue gasses can then escape. These can include lethal Carbon Monoxide if the flue is used for a gas burning appliance.

The adjoining house is to be demolished.   will i be affected?

Terraced or semi detached properties that share a Party Wall often rely on one another for support so if a building is wholly or partially demolished precautions must be taken to protect the stability and integrity of the Party Wall. Damage can also be caused by the vibration associated with large scale demolition and damp penetration if an exposed wall is not protected  against the weather.

Watson Woods Partnership



You should choose a surveyor who:- 

  • Has relevant  (i.e building professional) 


  • Is experienced
  • Is based relatively locally

You are advised to obtain references from your chosen surveyor.

We will be happy to offer you advice and if we are within a reasonable distance of your property we will be please to assist you further.

If you are located remote from our offices in London you can find a local Party Wall Surveyor from the Faculty of Party Wall Surveyors web site.

The Act requires that your reasonable cost are met but  that may not cover your surveyors fees if these are judged to be unreasonable so you have a duty to ensure that fees charged are reasonable.