Retaining Wall On Property Line Ontnio 1

[Jordan411]

Hi,

I recently ran into a situation where we needed to place a retaining wall on property line. If my foundation encroaches on the adjacent property is there any problems with this? I have looked for codes / rules against this to no avail. Any help on the matter would be greatly appreciated.

 

[Ron]

This will depend on the property boundary laws in your area. At the least, you will have to obtain permission from the adjacent property owner to encroach and legally you might have to be granted an easement for the foundation and for the construction.

Next you have to be concerned about the effect your retaining wall might have, both during and after construction, on the adjacent property. If their property is higher than yours and you are retaining their property, then you will have to protect their property from ANY lateral and vertical soil movement, particularly if they have a foundation within a zone of influence of your retaining wall. Further, it is difficult to install a retaining wall without some form of vibration. That can cause settlement of adjacent foundations and wall cracking. Be aware of this and mitigate vibrations by the selection of the construction technique.

If your property is higher than theirs, you have fewer issues to deal with, but there is still the issue of vibration and access during construction.

I would suggest a very thorough pre-construction condition survey of the adjacent property, noting and mapping any existing cracks, setting pins in the wall to check vertical movement and documenting all with notes, photos and video. The termination of all cracks should be marked so you can see if crack migration occurred during construction. You have a duty in the design and specification of the wall construction to protect the adjacent property. Approach carefully.

 

[msquared48]

I fully agree with Ron here.

Additionally, you will be designing an inherently inefficient wall (an L shaped wall) with the footing probably being as high as the height of earth retained, and the height retained height of soil also limited by the allowable soil bearing.

You may also have sliding stability issues and need a key at the base.

Mike McCann, PE, SE (WA)

 

[sam74]

You also might need to verify that there is not already some form of easement such as a utility easement. It was typical in one larger city where I worked to have property within the city limits having a 5' utility easement on either side of all property lines. Building a wall in that easement would require some sort of variance approval since you would be proposing placing a permanent structure in an easement if that applied to your case.