I have a document on which I regularly need to resize a double bordered box. This is becoming tedious and time consuming; Currently I have two rectangles which I resize and realign. I wonder is there no better way than to do this?

What I need is a double bordered rectangle object/path (doesn't matter), that I can resize and while resized keeps the same gap width between the lines.
When grouping two rectangles and resizing them, the distance between the strokes scales with.

See example: Left box is starting position, right side are the results: on top, what happens when resizing a group of two squares, below that the situation which we're looking for.

Can you select stoke type as double stroke from the drop-down menu? It should work.

Good luck.

Draw a rectangle then create a linked offset [Path > Linked Offset]. Drag the offset handle to create a smaller shape inside.

Use the node tool to resize the outer rectangle. The inner shape will automatically preserve the offset.

Select the inner and outer rectangle and duplicate them [ctrl+d]. The new offset should be linked to the new rectangle. (Copy and paste does not link the pasted offset.  A bug maybe?)

Multiple offsets can be linked to a single original path.

@kashi.deepak: I couldn't find any drop-down (I'm on v1.1.1) that had a double-stroke option (and could that then have any set gap?)
@Paddy_CAD: Works! Took me a bit of fiddeling, but I got it working nicely :-) I can even use the handles (not necessarily the node tool) to resize.

Perfect, many thanks!

Edit: On a side-note: for me, Copy-Paste works. It's duplicate that gives me problems, namely that I don't seem to be able to remove the link created by the cloning process...

I have a vintage MacBook and a more modern Win10 laptop both running Inkscape 1.1.1.  On macOS duplicating the shapes creates a new linked offset but copy/paste fails.  On Windows I see the opposite; copy/paste works as expected but duplicating fails.  Time to check the bug list.

Been working with it for a bit now, turns out that it doesn't work exactly perfectly... when resizing the boxes, sometimes the stroke width changes by a few tenths of mm's and sometimes the gap size changes as well. It's not a lot but enough to mess up alignments. It seems to be a bit hit-or-miss, I wish I could say when this happens. Perhaps I figure out why this happens, in which case I'll report back here.. could also be user error ;-)

Scaling objects can distort the paths in different ways for shapes, groups and clones.  Here's an earlier discussion that might shed some light on the issue.

https://inkscape.org/forums/beyond/scaled-path-results-in-stretchedsqueezed-strokes-how-to-restore-normal-stroke