When homeowners consider expanding into their lofts, it often makes more sense financially and practically than moving to a larger property. However, it’s essential to understand the potential risks of damage to party walls and neighbouring properties during such renovations, and to take proactive steps to minimise these risks.
Risks of Party Wall Damage
Party wall damage during a loft conversion project can occur due to several factors, such as the strength of the existing wall, the quality of materials in neighbouring buildings, and the care taken by contractors and structural engineers.
One of the main risks arises when steel beams are inserted into party walls to support the structure. To make space for these beams, pockets are cut into the wall, typically no deeper than half the wall’s thickness. However, if the contractor isn’t cautious, the brickwork can shift toward the neighbour’s side, leading to bulging, plaster cracks, and cosmetic damage on the neighbouring wall. In the worst cases, holes can be punched right through the entire thickness of the wall, causing significant distress.
Older properties (pre-1945) are at higher risk due to the possibility of weak or degraded mortar in the party wall. In these cases, it’s critical to avoid using power tools like percussive drills, and instead, hand tools should be used to minimise any disruption.
Roof Work and Neighbouring Property Damage
Replacing the roof during a loft conversion can also present risks, particularly where no parapet walls exist between properties. When the new roof meets the neighbour’s, there’s a chance that the junction can allow rainwater to leak if not properly weathered. This can also cause damage to gutters and downpipes. A common solution to this is the installation of bonding gutters, which prevent displacement of tiles and ensure a secure, leak-free junction.
Raising Party Walls and Fire Safety
In some loft conversions, particularly those involving a dormer or mansard extension, the party parapet walls are raised above the roofline. These parapet walls also function as a firebreak. In these instances, issues like proper waterproofing and fire safety must be taken into consideration, particularly when raising or altering the height of shared chimney stacks.
Protecting Neighbouring Properties and Maintaining Structural Integrity
When embarking on loft conversion projects, it’s important to protect neighbouring properties from potential damage caused by falling debris. We recommend using netting and protective barriers on scaffolding and on neighbouring roof areas. Additionally, removing chimney breast walls often connected to the party wall presents challenges. Careful consideration is needed to support the chimney stack and protect the integrity of neighbouring properties.
Also, it’s important to prevent soot from falling into the neighbour’s chimney, which could ruin carpets or damage appliances. During the works, gas appliances served by a shared chimney may need to be temporarily disconnected and later tested upon completion.
Final Considerations: Party Wall Agreements
When initiating a loft conversion, securing a Party Wall Agreement is essential. Don’t assume the neighbour will automatically agree in writing to the proposal. If they don’t, it’s necessary to appoint a qualified surveyor to draw up a Party Wall Award and ensure the project moves forward smoothly, with both parties’ interests safeguarded.
For expert advice or to initiate a Party Wall Agreement, please contact us at team@simplesurvey.co.uk.