How to split multiple rows in Calc?

I have a spreadsheet with about 20 rows, and I’d like to split each of them into 2 rows. The new rows should be merged with the current ones so the spreadsheet looks the same, or if not feasible, then every 2nd row could be empty.

Here are some examples:

Initial spreadsheet:
s1

What I want to get:
s2

Or alternatively, I could also use this:
s3

The goal is to add some stuff on some of the cells in rows 2, 4, etc.

It’s a puzzle for me. 2nd image: If you actually have merged A1:A4, B1:C2 and B3:C4 - what sense in it? Double row height, double column width for B and omitting C would do everything not only simpler but better, too.

@Lupp each cell has double the height (in rows) compared to the first image, it makes perfect sense. Double row height, double column width for B and omitting C are 100% USELESS because the whole point is I want to be able to add stuff in cells like A2 or C4 (unmerging some of the big cells), separately from “foo” and “baz”.

@Lupp I guess you thought image 2 was the final goal? No, it’s just an intermediary step so that I can make further changes. Having the cells already merged like that is good because I can start making a few additions without having to fix the whole sheet (as in the 3rd image).

Do you mean, it’s just a matter of colours and borders?

I really cannot understand where this should lead to. I still cannot see any functionality/purpose. Having just abut 20 rows and no calculations needed should mean: No complicated tricks! Just do it “by hand”.

Create a second sheet and fill in there the contents as you want them referring to the cells in the original sheet with the help of OFFSET.

To simply get some kind of better overview there can be used different means, and wich one might be preferable will depend on details of the data, and also on proposed further usage.

You may upload an example or describe it in detail if you want additional advice.

Taking your question literally: Why don’t you simply increase the row height?

Editing

With regard to the most recent comments I attach an example file. I will now retreat into my galaxy.
ask46156EnlargedCells001.ods

Please add more details about the first paragraph (what is that about filling in the contents and using OFFSET?)

Also, I’m not sure what you mean by “better overview”.

Increasing the row height won’t help because the number of rows won’t change. I want to add more information “between” the existing rows.

I simply cannot understand. If you want to only use your sheet as a visual grid for something typed in: Just draw your grid and type. If you actually want to use it as a spreadsheet, this will include applying some formulae and Calculations. Keeping information partly in the “main” rows and partly in intermediary rows would cause complications over and over. Add a column for your “remarks”, whether in one piece or for every primary column extra.

I think we must be from different galaxies as we can’t seem to understand each other at all. Yes, the sheet is mostly a visual grid, in this case I’m not doing any calculations, but how is that relevant?
What do you mean “draw your grid and type”?! Draw what where, using what? And how is that going to help solve my problem?

And what complications are you talking about regarding “main” and “intermediary” rows?! I just want to double the number of rows (inserting a new row after each initial row) and treat them all as regular rows afterwards. I don’t want to add “remarks” and I don’t want new columns. If you still can’t grasp the concept, think of a time table that currently has a row for each hour and I want to have a row for each half hour instead.

There isn’t a thing like “merged rows”. Calc allows for merging cells, not for merging rows or columns. The so called merged cell is an enlarged display of a foreground cell hiding one or more background cells. As I suppose spreadsheets not performing any calculations being rather useless, I assumed you also would have some formulae there. This is what regularly causes problems when merging cells. What you want might better be implemented by a text table in Writer.

When I said the new rows should be merged with the current ones, I meant each cell in a new row should be merged with the corresponding cell from the initial row. This extends to already-merged cells. About Writer, I tried it there and surprisingly it has a split feature that’s very close to what I want. It’s not as convenient as Calc though.