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Party wall to remain

Lena12

Registered User
Joined
Oct 20, 2023
Messages
9
Location
Toronto
Neighbour under construction. There is a party wall to remain as per the floor plan( see below). There is a new wall built beside the remaining party wall to support the new building. As per the Ontario Building code, is the proper enclosement required for the adjacent remaining wall? Currently, the remaining party wall is Exposed, which is adjacent to my side. I do not how to fix the issue.
Any suggestion? Thanks

Screen Shot 2023-10-20 at 8.04.56 AM.png
 
I don't find the sketch to be sufficiently detailed for me to understand what construction is existing, what's being built new, and how/if they are connected.

You called it a "party wall." Where is the property line? By definition, a party wall is shared between two structures on two separate parcels. Is this really a party wall, or is it an exterior wall with a zero setback from the property line?
 
It used to be a party wall, (both of our structures are 2 stories) but now the neighbor has built a new 3-story house with a new wall embracing the previous party wall( the old party has to remain). a party wall is not an exterior wall, as it is exposed and currently only supports my house.

from the front: Screen Shot 2023-10-20 at 3.25.02 PM.png
current state: Screen Shot 2023-10-20 at 3.25.30 PM.png

property line in red:



Screen Shot 2023-10-20 at 8.04.56 AM.png
 
I see a red line runnind down one side of what may be (based on the diagonal hatching) a masonry wall. The wall seems to be entirely on one side of the property line. Assuming the new construction is on the left, where is your wall and what is its construction?
 
Time out -- is that sketch a plan view? I thought it was a vertical section. To respond to this at all intelligently, I think we need to see a vertical wall section detail showing the full height of the party wall and how it's constructed.
 

Detail 1/S-17 is what I was looking for, but as drawn it leaves me with some questions. The way it's drawn, other than the foundation wall it conveniently DOESN'T show the construction on the left side (which I assume is you). It shows the eave of the proposed new roof projecting over onto your side of the property line. The new exterior wall -- above the foundation -- is not on the property line but offset by a few inches, aligning with the face of the new foundation wall. This presumably leaves a gap between the new exterior wall and the former party wall -- depending on how the former party wall was constructed above the foundation.

To be honest, if I were the building official I would not have accepted these drawings. Too many questions are not answered.
 
Detail 1/S-17 is what I was looking for, but as drawn it leaves me with some questions. The way it's drawn, other than the foundation wall it conveniently DOESN'T show the construction on the left side (which I assume is you). It shows the eave of the proposed new roof projecting over onto your side of the property line. The new exterior wall -- above the foundation -- is not on the property line but offset by a few inches, aligning with the face of the new foundation wall. This presumably leaves a gap between the new exterior wall and the former party wall -- depending on how the former party wall was constructed above the foundation.

To be honest, if I were the building official I would not have accepted these drawings. Too many questions are not answered.
Hi
Thanks for your reply. on the left side, is my house. from what is seen on site, there is no gap left between the new exterior wall and the form party wall. because the former party wall half is mine and half is neighbors' and they have to retain their half. However, we do not know if they going to put the flashing on the edge to close it properly or if they are going to leave it as is. I asked the city building inspector, NO reply. It leaves us in the gap, even if we want to fix the issue, we do not know the scope of work.
 
Hi
Thanks for your reply. on the left side, is my house. from what is seen on site, there is no gap left between the new exterior wall and the form party wall. because the former party wall half is mine and half is neighbors' and they have to retain their half. However, we do not know if they going to put the flashing on the edge to close it properly or if they are going to leave it as is. I asked the city building inspector, NO reply. It leaves us in the gap, even if we want to fix the issue, we do not know the scope of work.

Then detail 1/S-17 is incorrect. That detail shows the new house getting an entirely new foundation wall, built against their side of the common party wall foundation. The new all above the foundation is show to align with the face of their new foundation, NOT with the property line at the center of the party wall. And the detail conveniently does not show any existing construction above the foundation wall, so it doesn't provide any information about closing and weatherproofing the gap at the top.

But, as drawn, there is a gap equal to half the width of the original, party wall foundation between your wall and the new superstructure wall.
 
Then detail 1/S-17 is incorrect. That detail shows the new house getting an entirely new foundation wall, built against their side of the common party wall foundation. The new all above the foundation is show to align with the face of their new foundation, NOT with the property line at the center of the party wall. And the detail conveniently does not show any existing construction above the foundation wall, so it doesn't provide any information about closing and weatherproofing the gap at the top.

But, as drawn, there is a gap equal to half the width of the original, party wall foundation between your wall and the new superstructure wall.


"And the detail conveniently does not show any existing construction above the foundation wall, so it doesn't provide any information about closing and weatherproofing the gap at the top." ---that is what I am worried about. Are they going to close the gap such as putting flashing on the edge? I am so confused.
 
Respectfully, I think you should take your concerns to the building official. If the new wall of the new house is touching your wall, then the drawings (at least, detail 1/S-17) are incorrect, or the builder didn't follow the drawings. Do you have access to the complete set of drawings? The building official obviously does. He should be able to show you how that gap is going to be made weather-tight. If he can't show that to you, then you should file an appeal.

This situation creates an interesting conundrum: The new house will be (if I understand it correctly) higher than yours. This means that they will have to provide some way of closing the gap between their new wall and the existing party wall. That will require doing some work on your side of the wall, affecting your property. But they are not legally allowed to be on your property or to touch your property without your permission.

The more I think about it, the more I think you need an attorney to be involved. There are attorneys who routinely deal with construction issues and so will understand codes and construction language. The typical family attorney who handles things like will and trusts won't be of any help -- they'll spend lots of [billable] time trying to figure out what the laws and the codes say, and they'll still probably get most of it wrong. Call the local bar association and ask for a list of attorneys who specialize in construction and real estate law.
 
Folks - note that this is a Canadian question. I'm swamped, haven't the time to read/research, but Canadian Codes are in play. |

BTW, I wouldn't make a decision until I saw the construction of the supposed party wall.
 
Folks - note that this is a Canadian question. I'm swamped, haven't the time to read/research, but Canadian Codes are in play. |

BTW, I wouldn't make a decision until I saw the construction of the supposed party wall.

I am aware that it's in Canada and I'm not, which is why I haven't cited any code sections. I am also an architect, and architecture is architecture. When a drawing only shows part of the construction involved, it's an incomplete and uninformative drawing regardless of what country you happen to be in.

Presumably, there is an existing party wall from the top of the [party] foundation wall up to the level of Lena12's roof. That's omitted on the wall section provided, which makes it impossible to assess weather integrity.
 
I see two issues:
1. There is no actual rating provided for the exposing building face. It does look fire rated, but I don't see the hourly rating called out or the methodology.
2. The eave overhang is not permitted by 9.10.15.5(5)
 
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