One of the most popular questions asked by property owners is whether an excavation notice is covered by the party wall act. There are different types of excavations that the act covers and confirms why these excavations are notifiable to an adjoining property owner.
Most of the property in England and Wales were built around the turn of the century or around the 1930’s. These properties have many different things in common but the most common thing is that all of their foundations tend to be towards the shallower end of the spectrum, this will range anywhere from 100mm to 450mm.
The building regulations require foundations for new buildings to be a minimum generally of 1 metre deep, this means these foundations are much deeper than those of surrounding properties, especially older properties. The Party Wall etc. Act 1996 came into play with the works being legally referred to as notifiable under Party Wall etc. Act 1996. A notice of adjacent excavation will need to be given to all neighbours affected.
There are modern excavation works in construction that allows for a wide and varied range of different approaches to excavation.
– Mass concrete foundation are conventional trench foundations, this means that the contractor will dig a trench usually a minimum of 1m deep and anywhere from 400mm – 600mm wide. The trench will then be filled with concrete, forming a foundation with the structure above, this is usually a side or rear extension. These types of foundation are conventional and commonly used.
– Piled foundation tends to be used where the ground is more of a granular type, for example, more sandy or gravelly areas. The foundation is dug when a piling rig drives or drills into the ground, usually in excess of 3m deep. It is then filled with concrete and usually reinforced with some type of metal to add strength and stability. This type of foundation is less conventional for work such as a rear or side extension. On the other hand, this is becoming widely used generally speaking because they are easy to install, contractors can do these fairly easily and they are strong, which allows the structure above to bear the load.
– Raft foundation is similar to mass concrete foundation, but rather than the depth of the excavation and trench being 1m deep, a raft foundation sits on the surface of the ground which is where it gets its name from. The trench is usually around 100 to 200mm deep and once dug it will usually have timber shuttering to its perimeter with the entire area being filed with concrete – they might also use some metal reinforcements. The foundation will be able to support the structure but this is not used often because of the mounting cost that comes with it.
Not sure if excavations is covered by the party wall act? Have you received a notice of adjacent excavation? SevenOne Associates are happy to help with any excavation notices.