Rule for OSB + Plasterboard

[masj76]

Hello!

I am in the process of planning interior walls on the upper floor of a Smålandsvillan Mariannelund.

Most likely, almost all the interior walls (except for the bathroom) will follow the principle:
- Gypsum 13
- OSB 11
- Stud with insulation
- OSB 11
- Gypsum 13

The question is the choice of stud and CC measurement.

For the bathroom wall, I have the following considerations:

1. The CC measurement is not really such a big question, it feels like CC300 and 1200mm boards will do. But - can you use a 45x45 stud or will it be too unstable? The idea is to put tiles on the bathroom side...

For the other walls, I have the following considerations:

1. Should you use a 45x45 stud to get a total thickness of 93mm, and make it fit with door frames or go for 45x70, reaching 118mm - but then it won't be a perfect fit with the frames..?

2. Of course, it would be nice to use CC450 on the interior walls and use 900-width gypsum boards. However, the OSB boards are 1200 wide, so it still feels like CC600 is preferable even with 1200mm gypsum boards. Will it be stable with 45x45 if I choose that stud dimension?

Thanks in advance!

/Mattias

 

[mlkjhr]

Since you are placing the OSB on the inside, it dictates the spacing of the studs. I don't know if there is OSB with a width of 900. You can choose the drywall as you like since it doesn't need to be joined on a stud when you have OSB behind.

 

[Milkshaken]

The bathroom cc30 yes.... Lay down the OSB, then you don't need to think about the load-bearing capacity. Otherwise, I would go with 70 studs, and 70 insulation, it doesn't flex much then.

 

[Nene]

45x45 may not be a sufficiently rigid construction for tiling, there is a risk of cracks in the grout. You could go for 70x45 c/c 30 and WAB (wet area board) 12.5 mm on the bathroom side and OSB and renovation plasterboard on the other side. The wall will then be 100 mm thick.

 

[Tanse]

I am probably for 45x70. There are also door frames that are slightly wider to fit walls that are 118 mm deep. They do cost a bit more than standard, though.

 

[xibeca]

OSB is available in 90 width.

 

[prototypen]

Do NOT join OSB and gypsum in the same place, it will be easier to get a smooth wall with staggered joints.

Protte

 

[masj76]

Thanks for all the input!

So, it will be 45x70 on the studs straight across! We'll see later if it will be CC450 or CC600 for the other walls, with a bit of luck I'll also find OSB 900x~2400 locally when the time comes, then it'll probably be cc450...

I will look for frames for 118mm, it feels like +/- 1-2mm won't be a problem for the frame width either...

/m

 

[HEPO]

Think 90 plasterboard for everything in the world. It's hard enough to get that board up the stairs. A 120 board, I dare not think about how that would be done. As for OSB, you can always screw it horizontally. I myself chose to split the OSB into two 60 boards to get them up in my Lammhult. Some 120 boards were carried up, but there are guaranteed marks on the walls and stairs after that.

As for stud choice, I have no experience with 45 studs and have used 70 with cc 45 and 90 cc 30 in the bathroom. There are also frames for 118 mm wall thickness. Maybe not at Byggmax, but I would think it is quite common. Your planned construction with double boards and 70 studs must be among the more common ways to build a wall?
http://www.bygghemma.se/inomhus/inn.../karmar/karmsidor snap-in vit/p-131550-131558

 

[nimhed]

A tip is to use 45x70 or 45x95 on the flat. It will be stiffer than 45x45 but the total will be like with 45x45. Then I would choose the spacing between studs so I wouldn't have to cut the insulation.