I'm in area 31 and need to get new flooring on our large open Attic. Any help on the best approach, Artisan, wood to use, where to buy it etc would be much appreciated. We know an excellent local builder but he may be too busy to help us in the short term.
I'm doing precisely the same thing in my son's house over two rooms which are each approx 4m by 6m.
We're putting one 12 by 24cm beam across the 4m span
and approx 3m50 long 6 by 17cm beams (they meet in the middle) spaced every 40 / 50cm for the 6m span. All wood is "sapin" - no "douglas" available.
Floor will be boarded with "panneau OSB3 rainuré" probably in 22mm.
We pick up all the material at the local sawmill or construction shops because we have suitable vehicules.
You can get your material delivered or rent a vehicule from the shop.
Brico D offered 1 hour's rent free if you buy for over 350€ (verify please).
Most wood is not seasoned and can warp alarmingly. Check for cracks, knots, rot and other signs of weakness.
Sawmill (scierie) prices can be cheaper. They may have already seasoned beams that will not warp. Check if you have one locally and visit.
Take care to avoid wood treated with that yellow stuff if you think that you might like to leave your beams apparent. Don't try to plane or sand them, they'll poison you!
Don't forget to wire electricity between ceiling and floor.
You may need planning permission if the space is for "living" rather storage. You may need planning permission for new windows in the roof space. I' ve been through that in France.......lots of paperwork, but the path is well trodden and works well. I found the fonctionaires very helpful, telling me size limits, calculation of living space, words to avoid on the forms etc. As usual in France it all starts at the Mairie.
Many thanks for the great details, I will need to decide if the attic will be just used for storage then a lower cost solution would be ok. Your reply has been a great help to make me think that we could use use the large space for rooms at some future stage.
Another thing to think about......by starting at the Mairie you may also trigger an increase in taxe d'habitation. I'm not sure of the rules and regs......but ask and be prepared. Perhaps others here know more?