Recently I completed a North Shore project that reinforced for me the issues a structural renovation can cause. Even on a small North Vancouver or West Vancouver project you can run into unexpected things for which you need to come up with creative solutions.

A couple of things were immediately noticeable upon inspection of the home. The laundry room coming off the house was underbuilt and it was likely an afterthought. It appeared to have once been a deck that was closed in at some point. The main issue was the supports that held up the structure. The deck sat on 4 inch posts, which then sat on preformed concrete blocks. The blocks were slightly buried but nowhere near the frost-line (which in Vancouver is 18 inches below grade). This was another clear sign that the structure did not originally started life as an addition. This construction would be suitable for a deck, or maybe a shed, but not for a part of the home that supports walls and a roof.

Renovating the Structure

The bottom of the extension was also framed in an odd way as the joists ran parallel to the house. This was an issue because the most logical way for me to re-support this structure would have been to sup-port it off the ledger board at the house and then a beam at the opposite end running from one post to the other. This design however required the joists to run perpendicular to the house.

I got on the phone with an engineer and we devised a solution. I would replace the concrete blocks with new 2 foot-square footings supporting 10 inch cylinders projecting out of the ground. The 4 inch posts would then be replaced with 6 inch pressure treated posts, saddled to the new footings. The joists on the extension itself would be doubled up, including rim joists. On the furthest side I would build a beam by packing it out with four 2×6’s carried by another 6 inch post. Lastly I would use joist hangers to help secure the joists to the rim joists.

The real challenge was in executing this job. I needed to start at the top by first beefing up the floor. To do this I had to run two shoring beams perpendicular to the house. This was so that I could catch all the joists at once, as I needed to cut them away from the rim joists to fit a second rim joist in place. Once this was complete I rotated the shoring so that it was parallel to the house and removed the current posts and blocks.

With this in place it allowed me to dig and place my footings. It was cold enough outside that the concrete needed to be kept warm in order to cure properly so I encased the extension with polyethylene and waited a week to allow the footings to cure properly. I then installed the 6 inch post over the footings and underneath the beam. Lastly I removed the shoring and backfilled the holes.

The most thought-provoking part of this renovation was the adaptation of the plans, as well as the need to set up shoring one way to carry out one task and then rotating it to complete the job. But I enjoy a good challenge, and like this one if you approach it with creativity and planning then every new project holds the opportunity for conquering new ground.