Thread: Help with leveling floor

Another type of packer is rectangular which I used to level the post of a gazebo.
Available in a couple of sizes, and multiple thicknesses. Macsim Fasteners 72 x 100 x 2mm Blue Half Shim - 8 Pack - Bunnings Australia & Macsim Fasteners 150 x 100 x 5mm Yellow Full Shim - 4 Pack - Bunnings Australia
Using my laser level I visited the site a week before construction commenced and worked out what the height difference was between the four posts and bought packers accordingly. Even pre drilled the thicker ones.
I am confident that they withstand the weight of the structure and will not rot or warp over time.

This is not really a viable solution for you however it offers ideas as another approach / option. No lasers back then either - all done by automatic "dumpy level" & surveyors box staff.

In 1981 as a young surveyor I assisted with the setup of a Hydroair truss plant in Cairns. Dad was the truss estimator designer and roped me into the project. It used electro-mechanical pedestals for the web intersection clamps so the floor was constructed with 2400 x 1200 x 12 mm steel plate with a flatness tolerance of =-1mm. The special order steel plate was then to be installed on a grid of steel shims / packers placed at 600 mm grid intervals. Floor size was ~35m x 12m (5 sheets wide) iirc. However it was not a single rectangle, rather two intersecting triangles with stepped sides, to permit multiple simultaneous setups for girder, main, & jack trusses etc for production efficiency & economy.

However the only suitable industrial shed available that it was to be installed in had been used for bulk storage of tin concentrate in bags by the previous long term tenant. The massive weight on the industrial shed's concrete floor which was constructed on reclaimed marine swamp resulted in considerable uneven settlement / deformation. The deformation varied from a few millimeters at the walls to near 150 mm in the center of the shed in places. Surprisingly the floor had very few significant cracks as the deformation was almost catenary like. The supplied packers, all sub 10 mm were all but useless so we had to come up with a viable and safe option as workers constantly move on & off the steel floor platform all day. The uneven step rise at the leading edge of the platform was a major issue. We had similar issues with installing the OH gantry that carries the press as the Portal Frames were no longer co-planar either for walls or roof, though that was an easy fix relative to the floor nightmare.

We used short lengths of 50 mm SHS on end as packers, and for the not so short packers 75 mm SHS to resist toppling at the sheet intersections and as we placed the sheet we tack welded the intersections and edges. A hell of a lot of work, with 3 drop saws running almost continuously for days, and the additional materials but it performed efficiently certainly until 1987 and well into the 1990's with minimal issues afaik. I lost contact with the plant owner after Dad passed in late 1987.