We've just had a loft conversion done and I now need to buy and lay the flooring.

My experience of doing flooring has been the living room and hallway, in which I installed solid maple strip, with hidden nails. The result was great, but hard work with the manual hidden nail gun + sanding + several coats of varnish.

I'm looking for an easier install for the loft room, which is about 30 sq metre, with lots of corners etc.

I've looked at some of the numerous suppliers online and I feel overwhelmed by the choice and variation in pricing etc. I'm looking for solid wood (not laminate), preferable 150mm wide planks. Oak is a favourite, but there are so many variants, I'm scared of getting it wrong.

So here are my questions - if anyone can advise:

What do the various grades mean, e.g. rustic I assume means more knots in the case of oak ?

What sort of price range should I be looking to spend per m2 ? Oak plank seems to vary massively. Maybe avoid anything sub £25 per m2 ?

Are there any woods that should be avoided - I found a good price on birch, which I really like the look of. Is birch any good for flooring ?

What's the best way to fix down the floor onto chipboard - hidden nail ? Do I need a foam membrane underneath ?

Thanks for any advice

cf