I bought some tongue and groove floorboards. I noticed the tongues and grooves were not centered in the edge but were offset. 

```
   ┌───────────────────────────────────────────┐ 
 ┌─┘                                         ┌─┘                      
 └─┐                                         └─┐
   │                                           │  ← thick side
   └───────────────────────────────────────────┘

```

I guess there must be some reason for it. There must be some benefit.

**Which way up should I lay these, as shown in diagram or the other way up?**

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P.S. To make sense of comments & parts of answers that relate to the specific boards I was using - see [prior revision](https://diy.stackexchange.com/posts/81563/revisions).