What needs to be in place before a party wall can be underpinned in a semi detached house?

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Posted by: from Toronto
8/6/2015 at 5:59:05 PM

My neighbour is planning to underpin part of our mutual wall by digging down 1 foot underneath to put in a support. What do I need to see from them to make sure my house is secure?

The whole house is being totally renovated top to bottom. Do they need to show me building permits for everything before they start?

Does an architect need to draw up plans?

Do I need to have a building permit for my side too?

How much insurance should my neighbour have?

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Date/Time8/6/2015 at 10:36:51 PM


I would ask if they have an emgineers report and the proper permits. The engineers report descirbes the type of ground, stress levels and items that may become structural issues if not done properly. The permits describe what work is intended and an inspection must be done at specific stages of the project to ensure the work meets all the safety codes.

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Date/Time8/6/2015 at 10:38:50 PM

Hi Tara,

There is (3) thinks needs to be done: 1: He needs Your written approval, 2: Building permit, 3: Structural engineers drawing. Architect is not important.

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Date/Time8/7/2015 at 8:27:16 PM

Your side should be supported same as there's with shoring posts and 6*6 running between them across the joists or steel beam. And permit must be posted in front window or door. They dont have to show you specifically because its suppose to be visible to the public. But if they do the job right don't complain because your basement will always be dry.

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Date/Time8/7/2015 at 11:01:23 PM

Hi Tara,

I don't see how they could do a project like this without actually coming into your home, if only to document existing conditions. You may want to get an engineer of your own as a second opinion and definitely check with your own insurance guy to see what he would ask for on his own house. He would probably want the other owner to add additional coverage just for you. I would also do a lot of photo documentation of your entire house, not just the common wall in the basement. If it lets go or even moves a little, damage could happen all the way up.

There are many potential issues that you have to cover. You are making a good start by asking questions here but you should check with your own team. A lawyer would probably create a document that protects you and would require the owner AND contractor agree to it to allow the work. He might even request that a bond be posted to cover any potential damages.

Good luck with it!

Jim Kuzma

Kettleby Handyman

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