How should the floor be cut when building an interior wall?

[FSven]

Hi!

I'm new to fixing and would appreciate some guidance on the following steps for building an interior wall. I'm going to build a wall on the upper floor of the house, which is currently one large room, to create two. There is laminate flooring. The plan is for the wall to be "permanent," and I therefore plan to cut into the floor for the sill. I've read that for 70mm studs, I should allow 90mm to leave an expansion gap for the floating floor. I've also read that the drywall shouldn't be mounted flush against the subfloor but a few millimeters above the laminate. I'm also planning to install a new door and frame and have been wondering how best to proceed.

1. Is it sufficient to place a wedge at the bottom of the drywall to create ample space for any future floor replacement of greater thickness?

2. Should I only cut the existing floor where the sill will be, or should it be divided into two floating sections - would an expansion gap of about 20mm where the door threshold will be sufficient? Or should it be left completely intact and allow both rooms to share the same floating floor?

3. Is it a good idea to put the new door frame on the existing floor? Or should it stand against the subfloor? The former seems easier and nicer, but maybe I'm missing something?

Big thanks in advance🙂

 

[maah]

Are you only going to have plaster on the wall or OSB + plaster?
I would have cut out the floor so that studs + OSB + plaster fit so that the floor doesn't end up under the wall panels.

1. See above.

2. Divide it into two sections with an expansion joint under the threshold.

3. The door frame should stand on the subfloor but the threshold should lie on the finished floor.

Don't take everything above as an exact guide but that's how I would have done it.

 

[FSven]

Are you only using gyproc on the wall or OSB + gyproc?
I would have cut out the floor so that the studs + OSB + gyproc fit, so that the floor doesn't end up under the wall panels.

1. See above.

2. Split it into two sections with an expansion joint under the threshold.

3. The door frame should stand on the subfloor but the threshold should be on the finished floor.

Don't take everything above as an exact guide, but that's how I would have done it.

1. Only gyproc. I also thought first to cut out for the framework + gyproc but read somewhere that you sacrifice valuable space for the expansion joint. I don't need a world-class result, but I want to avoid redoing it right away at least You think it's not needed then. Thanks!

2. Thanks for the input!

3. I suspected that. I was thinking that the advantage of placing the frame on the floor is that you initially avoid potentially having to saw the door leaf. Not sure how much space there is between the bottom of the door leaf to the bottom of the frame, so to speak. Maybe there's a standard for that?

 

[Larsa]

The door frame should not rest on the subfloor. The door leaf might need to be trimmed if so, and it will result in an unattractive movement joint.

 

[maah]

The door frame should not stand on the subfloor. It might require the door leaf to be cut, and it would result in an ugly movement joint.

You're right. I was thinking wrong.
I've installed a bunch of frames, and of course, all of them stand on the finished floor.

During renovations, however, it often happens that the frame is left in place and the new floor is laid against the frame.

 

[Larsa]

You're right. I was mistaken.
I have installed a bunch of frames and they all, of course, stand on the finished floor.

However, during renovations, it's common to leave the frame in place and lay the new floor against the frame.

Yes, then you saw off the frame and let the floor go underneath. Then you might need to trim the door at the bottom.