Installing Wood Floor in Two Rooms

[Doiknowwhatimdoing]

I'm looking for some tips on laying oak flooring.
I'm looking to lay 20mm boards (B&Q 125mm wide planks) in a living and dining room.
The 2 rooms are connected by French Doors. The living room is about 6x4m and the dining room comes off the living room as a dogleg. The dining room is about 4x3m.
Is it safe to install the boards in one section or should I leave an expansion gap in the french doorway?
If I install in one section I'll have a gingle run or boards about 8m in length. I'm planning on using Elastilon as the base material over a concrete subfloor. Will that make any difference?
I've read that i need to leave a bigger gap around the edge of the room as the humidity is low at this year is 25mm OK?
Cheers!

 

[WoodYouLike]

It is always best to treat every room as a separate entity and install a threshold - divider in between. EVery room has its own "climate"
Then you calculate per room the expansion gap you need based on the width the rows of boards will be. E.g. room 6 x 4 and installing parallel the longest wall, means 4 meter wide floor: 4 x 4mm (4mm per meter wide) = 16mm. Same room, but now installing parallel the shortest wall, means 6 meter wide floor: 6 x 4mm = 24mm gap.
In winter you indeed make the gap a little bit wider, say 18 example 1 and 26 example 2

AND DON'T FILL THE GAP WITH CORK!

With Elastilon on concrete you have to lay a DPM sheet first

 

[Doiknowwhatimdoing]

Thanks for that tip. Much appreciated.

I didn't know about different gaps along the long and short edges, would have done it square!

Thanks for your help!

 

[WoodYouLike]

Once you calculate the expansion gap you minimum need, that's normally the width of the gap you use everywhere - just to keep it simple so you can use one and the same thickness in spacers