Bay windows are a common feature of Victorian, Edwardian and 1930s properties. Extending, rebuilding or enlarging an existing bay can improve both the appearance and internal space of a home.
But could the works require a Party Wall Notice?
The answer depends on the extent of the construction and, particularly, the new foundations.
Does altering a bay window automatically trigger the Party Wall Act?
No.
Replacing windows within an existing bay would not normally require Party Wall procedures.
However, rebuilding or extending the bay may involve:
- new foundations;
- deeper excavation;
- structural alterations;
- new walls close to a boundary; or
- works affecting an existing party structure.
These elements should be considered separately.
New foundations are often the key issue
An enlarged bay may require new foundations extending deeper than the original structure.
Where excavation takes place within three metres of a neighbouring structure and below the level of its foundations, Section 6 of the Party Wall etc. Act 1996 may apply.
For a wider explanation, see our Beginner’s Guide to Section 6 Party Wall Notices.
Semi-detached properties
Bay windows on semi-detached houses are often positioned relatively close together.
Even a modest projection may therefore involve excavation within the relevant distance of the adjoining property.
The actual foundation depths need to be considered rather than simply measuring the distance between the buildings.
Structural alterations
If the project involves removing masonry, installing structural beams or altering a shared wall, Section 2 may also become relevant.
Our Section 2 Party Wall guide explains the types of structural works covered.
Check before construction
Small projects are often programmed quickly.
That makes it particularly important to identify Party Wall requirements before the builder is ready to excavate.
Simple Survey can help
If you are rebuilding or extending a bay window, send Simple Survey your drawings and foundation details.
Visit our Party Wall Surveyor service page and we can advise whether notices are required before work starts.