Laying oak floor - end does not rest on a joist?

[elimn8or]

Hi all. Have battened out my room in preperation for laying solid oak 120mm tongue and groove flooring using the secret nailing approach. Im a bit confused as to what you do when a floor board end does not finish on a joist. My packs of flooring come in variable sized board lengths meaning that it will be inevitable that many planks will not finish on a joist; this is more of a problem with small planks. Usually i would just lay 18mm plywood first but ive been told its a waste of time since each board will reinforce its neighbours. Im just not 100% sure this analysis is true. I know they interconenct via the tongue and grove, but if a board has, lets say only one nail in it, and then someone puts all of their weight on it, will its neighbours provide enough strengh to take the weight via the tongue and groove? what is the opinion of the pro's? Bear in mind that 15 sqm of 18mm ply will come under £200.

 

[WoodYouLike]

You have to make sure that every board connects with at least three battens.
If you have a load of small boards, you have a big problem.

 

[elimn8or]

hmmm - each board has to conenct to at least three battens.....? oh well i better get on and order in the 18mm ply then.

ill measure each board when i get home. I space the battens every 400mm from their centres plus there are noggins but these will be too sparse for providing support lengthways.

 

[mattysupra]

now this is why i always say to lay plywood first. Much better and stronger job.