Snap a Slab to a Polyline or to a CAD Line

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Hello, I've searched the forum and tried the reference manual, but cannot get object snaps to work when I try to snap a concrete slab to a polyline or to a single CAD line that represents the outline of my foundation.  I can get the two aligned fairly closely by manually moving the slab, but can't get it 'spot on' because it won't snap to the polyline or to a CAD line even though I have all snap behaviors on in 'Snap Settings' (under 'Edit'). 

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Just tried in Pro 2109 -- should be the same as 2018, and it snaps to CAD.


Can you use temporary dimensions to move?


And why draw a CAD line to represent your foundation, then draw a slab -- why not just draw the slab?


You can convert a closed polyline to a slab too. Select the polyline, choose Convert Polyline, pick Slab.

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Hi Eric,


See the image below.  I am currently laying out the footers for my home plan.  What I've done is to create a stem wall foundation, outlined the foundation 'footprint' with CAD lines, and then deleted the stem walls.  I'm now inserting the continuous footers on which the CMU piers will sit.  I've drawn the footers as a slab, and am now trying to slide the sized footers into the foundation outline such that they meet up exactly with the outline.  For some reason, the slab footers won't snap to the CAD lines which represent the perimeter of the foundation.  Open to any and all suggestions.  I'll have six rows of footers, all tied into a footer which will run around the perimeter.  The result will be a 'grid' of footers upon which the piers will sit.

1229 SF - 2018-05-03 - Foundation with Continuous Footers.dxf

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A dxf file is useless. Please post your plan file, or images -- use the Snipping tool if on Windows.


Why a continuous footing? I've seen plenty of houses sitting on piers, but none with continuous footings.


Why not a slab on grade? 


Draw a slab the correct size. Use point-to-point move to place it.


Draw a CAD box (closed polyline) which will snap to your other CAD line work, and convert it to a slab.


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I'd post the plan file, except I have extremely poor internet here on the farm and my plan file is so large that I think it exceeds the maximum size for attachments.  Below are two images.


I'm building on soft clay, and the interlocked continuous footers allow the house to 'float' as a unit rather than using individual 'spot' footers.  We considered slab-on-grade, by far the most common type nowadays in Texas because it is easy and quick for the builder, but my wife and I both prefer the look of a 'raised floor' foundation.  And, I like the easy accessibility of plumbing and other utilities.


The foundation plan obviously isn't complete since three of the horizontal footers are still lacking as are the two vertical perimeter footings.  Also, I have not yet added the piers themselves.  Our first step is to pour the footers, and we hope to do the trenching next week, but I need to get exact measurements for spacing - and that's tough to do since I can't get the footers to 'snap' to the CAD lines.

Continuous Footers - Floor Plan View.jpg

Continuous Footers - Perspective Framing Overview.jpg

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