Have purchased 150 x 19 mm solid oak boards, all quite long 1500 to 3000 T&G for kitchen/dining room (whoops). The room is L shaped 3 to 4m wide by 8.5m long. Concrete floor with dpm laid 5/6 months ago. However, because of change of plans now need to raise finished floor above central heating pipes.
Was going to use dpm, secret nailing 25mm ply battens (the battens not fixed to the concrete) but have lost my nerve reading everything on the web! Have successfully laid 90mm T&G oak floor in this way previously. But now concerned about extra width of board and location within a kitchen leading to problems. I am concerned about the clamping effect of a portanailer on the boards. Like the idea of floating floor to minimise risks, using a dpm under a 25mm ply sub floor. I don’t want to raise the floor with a screed because of the drying time.
1. Is it feasible to lay ply sub floor over concrete in this way, even if not “the done thing”?
2. If so do I need to fix the ply to the concrete or can this also be floated?
3. I presume I would still need a dpm?
4. If I have to screw the ply this will piece the dpm – is this a problem or do I use a liquid DPM and adhesive only?
5. If I don’t need a dpm but still need to fix the ply to the concrete do I need to screw and glue with a bitumen adhesive or something similar
6. Is WBP OK and does it need to acclimatise?
If the above is not feasible I have read that using a pneumatic nailer will more loosely fix the boards to battens than a portanailer. Apparently this may allow the floor to expand without damage and the floor could acclimatise in situ (English Timbers website). What do you think of this advice and where can I hire one of these in Cumbria!! If I can’t get hold of one, what am I to do!!
Was going to use dpm, secret nailing 25mm ply battens (the battens not fixed to the concrete) but have lost my nerve reading everything on the web! Have successfully laid 90mm T&G oak floor in this way previously. But now concerned about extra width of board and location within a kitchen leading to problems. I am concerned about the clamping effect of a portanailer on the boards. Like the idea of floating floor to minimise risks, using a dpm under a 25mm ply sub floor. I don’t want to raise the floor with a screed because of the drying time.
1. Is it feasible to lay ply sub floor over concrete in this way, even if not “the done thing”?
2. If so do I need to fix the ply to the concrete or can this also be floated?
3. I presume I would still need a dpm?
4. If I have to screw the ply this will piece the dpm – is this a problem or do I use a liquid DPM and adhesive only?
5. If I don’t need a dpm but still need to fix the ply to the concrete do I need to screw and glue with a bitumen adhesive or something similar
6. Is WBP OK and does it need to acclimatise?
If the above is not feasible I have read that using a pneumatic nailer will more loosely fix the boards to battens than a portanailer. Apparently this may allow the floor to expand without damage and the floor could acclimatise in situ (English Timbers website). What do you think of this advice and where can I hire one of these in Cumbria!! If I can’t get hold of one, what am I to do!!
