Cost for partial 2nd floor addition?

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Posted by: from Waterloo
11/7/2020 at 12:30:15 AM

Hi All, I have been working on modelling a potential 2nd floor addition for my house and I would love to get a ballpark figure of what I would be looking at to have this built.

My home is a bungalow, with an existing loft. I would like to add an addition above a section of my home that would connect with the existing loft to expand my 2nd floor.

I have attached several photos of drawings and 3d models that I have. The area with the blue lines indicates the location of the proposed addition. At a high level, this would involve ripping up the roof in this section, building directly on top of the existing load bearing walls, installing a new roof and tie-ing into the existing. Also would include plumbing/electrical/hvac etc..

We have put a lot of thought into this, and I can add more details if required - please let me know. But I am hoping to get a ballpark figure for what this would cost.

Any responses would be greatly appreciated. Thanks in advance.

Cost for partial 2nd floor addition?
Cost for partial 2nd floor addition?
Cost for partial 2nd floor addition?
Cost for partial 2nd floor addition?
Cost for partial 2nd floor addition?
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Date/Time11/7/2020 at 5:07:33 PM

Hi Jason,

My names James with Valour Renovation and Design.

Generally addition prices start in the $150-175/sqft range and can run well past $250/sqft depending on finishing.

For a more detailed price I d suggest meeting a few qualified contractors and starting to work with one you like

They can help you get a full set of plans, permits and work through detailed costing of the project.

Hope this helps

James Closs

Project Manager

Valour Renovation and Design

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Date/Time11/7/2020 at 5:08:32 PM

Hi john from gardco renovation and design.

We are starting an addition on Monday morning very similar to yours.

I can tell you that it is 400 sq feet with a complete new roof. This price included everything you talked about.

The cost is 89,888 plus hst. That should give you some idea of the number. That price includes two bedrooms bathroom etc.

Hope that helps.

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Arthur from KM&C Homes in Kingston
Date/Time11/7/2020 at 6:17:48 PM

With out see it I would say around 250k

Thank you,


KM&C Homes

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