Just finished the exterior and now going for the interior, the big question is the choice of boards? I've gotten different answers/tips depending on who I ask, so I'm trying to get wiser here..?
To start with, I've already started tearing off the horrible Masonite boards on the walls, bloody boring, but someone said it was necessary?
For the outer walls, which are plank walls, I'm thinking OSB+gypsum since I've changed the size and shape of some windows, the question here is which gypsum board should I choose? 13mm or 6mm?
Regarding the inner walls, I have a mix of both raw spruce and plank walls, I’d rather avoid OSB here because I got the impression that the walls become very thick then? -Is it okay to put 13mm gypsum directly on a somewhat uneven raw spruce or plank wall? Or is OSB preferred here too?
To start with, I've already started tearing off the horrible Masonite boards on the walls, bloody boring, but someone said it was necessary?
For the outer walls, which are plank walls, I'm thinking OSB+gypsum since I've changed the size and shape of some windows, the question here is which gypsum board should I choose? 13mm or 6mm?
Regarding the inner walls, I have a mix of both raw spruce and plank walls, I’d rather avoid OSB here because I got the impression that the walls become very thick then? -Is it okay to put 13mm gypsum directly on a somewhat uneven raw spruce or plank wall? Or is OSB preferred here too?
Hello and welcome to Byggahus
I guess most people use 13mm plasterboard....
Regarding "somewhat" uneven raw timber or plank wall....how uneven is it? ...without having seen how it looks, it probably depends more on your requirement for what the final result should be.....
I guess most people use 13mm plasterboard....
Regarding "somewhat" uneven raw timber or plank wall....how uneven is it? ...without having seen how it looks, it probably depends more on your requirement for what the final result should be.....
It usually works well with 13 drywall and is preferable, as the drywall cannot be screwed into the dips and requires a somewhat even surface. But if you screw on the heights, it should be fine; otherwise, OSB.
Which plasterboard you should use depends on the desired result and how much work you are willing to invest.
6mm plasterboard is usually relatively flexible and often has a slightly harder surface, making it less likely for screws to go through easily. This means it's not as critical for the underlying surface to be flat. The downside is that the wall will look like a bulging fiberboard wall.
13mm plasterboard, conversely, is significantly more dimensionally stable, but it is very easy for screws to go through if there isn't a solid backing where you are screwing.
I have a 1920s house with walls of 2" or 2½" tongue and groove planks, as well as some interior walls made of old rough wood. Where I haven’t chosen to build out the walls for other reasons, I have screwed plasterboard directly onto the old substrates. I have tried both 6 and 13mm plasterboard but now almost exclusively use 13mm because the result is more attractive. I have proceeded in the following way:
Plank walls: Start by nailing or screwing any loose planks. Then remove all old nails that held the fiberboard and other unnecessary metal debris. Next, go over the wall with a carpenter’s axe and a heavy plane, like a jack plane, and remove all protruding bumps down to some sort of "average level." I’ve also a couple of times replaced a few planks that were warped by several centimeters that I couldn't bother to axe flat. Finally, try to identify where the screw rows in the plasterboard will land and fill any depressions there with wedges, fiberboard strips, or a few layers of thick paper. It doesn’t need to be perfect, but with 13mm plasterboard, it’s good if there aren’t depressions of more than a few mm, otherwise, the screws will go through. Long, gentle bends, like a gap of 5-10mm in the middle of a 1.2m level, don’t matter much; a 13mm plasterboard is that flexible. It's more a matter of aesthetics and how much work you want to put into making the wall as flat as possible at the end.
Rough timber walls: Essentially the same as the plank walls, but it's usually easier to replace bad boards than to try leveling them. If they’re nailed with cut nails, you often need to add a lot of new nails since the cut nails are tapered and thus loosen when the wood dries. Since the rough timber in my house is generally horizontal and fairly warped, it's harder to prepare for the screw lines. The solution is usually to make a lot of small fiberboard pieces that are inserted as needed between the rough timber and the plasterboard when a screw ends up where there’s a depression behind it. This only works in the joints, but if a screw goes right through when you're screwing in the middle of the board, it’s no worse than placing a new one just above or below.
6mm plasterboard is usually relatively flexible and often has a slightly harder surface, making it less likely for screws to go through easily. This means it's not as critical for the underlying surface to be flat. The downside is that the wall will look like a bulging fiberboard wall.
13mm plasterboard, conversely, is significantly more dimensionally stable, but it is very easy for screws to go through if there isn't a solid backing where you are screwing.
I have a 1920s house with walls of 2" or 2½" tongue and groove planks, as well as some interior walls made of old rough wood. Where I haven’t chosen to build out the walls for other reasons, I have screwed plasterboard directly onto the old substrates. I have tried both 6 and 13mm plasterboard but now almost exclusively use 13mm because the result is more attractive. I have proceeded in the following way:
Plank walls: Start by nailing or screwing any loose planks. Then remove all old nails that held the fiberboard and other unnecessary metal debris. Next, go over the wall with a carpenter’s axe and a heavy plane, like a jack plane, and remove all protruding bumps down to some sort of "average level." I’ve also a couple of times replaced a few planks that were warped by several centimeters that I couldn't bother to axe flat. Finally, try to identify where the screw rows in the plasterboard will land and fill any depressions there with wedges, fiberboard strips, or a few layers of thick paper. It doesn’t need to be perfect, but with 13mm plasterboard, it’s good if there aren’t depressions of more than a few mm, otherwise, the screws will go through. Long, gentle bends, like a gap of 5-10mm in the middle of a 1.2m level, don’t matter much; a 13mm plasterboard is that flexible. It's more a matter of aesthetics and how much work you want to put into making the wall as flat as possible at the end.
Rough timber walls: Essentially the same as the plank walls, but it's usually easier to replace bad boards than to try leveling them. If they’re nailed with cut nails, you often need to add a lot of new nails since the cut nails are tapered and thus loosen when the wood dries. Since the rough timber in my house is generally horizontal and fairly warped, it's harder to prepare for the screw lines. The solution is usually to make a lot of small fiberboard pieces that are inserted as needed between the rough timber and the plasterboard when a screw ends up where there’s a depression behind it. This only works in the joints, but if a screw goes right through when you're screwing in the middle of the board, it’s no worse than placing a new one just above or below.
Thanks for the good answer that led me to a decision about OSB + 13mm gypsum on the exterior walls and only 13mm gypsum on the interior walls. 
Does one have the same problem when using a screw gun or is one saved by the depth stop?
My experience is that the screws often seem to hold very well even when there is something wrong behind them because suddenly, a few seconds after removing the driver, they go right into the sheet. So I don't think an automatic screwdriver helps much; rather, I believe you have a better feel with loose screws and a regular screwdriver when dealing with such uneven surfaces. After a while, you learn to sense when things won't turn out well and can backtrack and move the screw before there's a big hole to fill.
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· Stockholms Län
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I agree with the concerns about 13mm plasterboard. If there isn't support directly behind the screw, it goes through very easily or the board breaks.
I would go with 6mm boards as they are much tougher and more moldable against the existing wall. They're also quite nice to work with since the flexibility is okay.
Alternatively, you could install type 28x70 battens first and then OSB+13mm plasterboard. But this involves much more work and takes up space. Plus, it feels unnecessary since OSB is meant for mounting things, which your existing walls can handle just fine.
I wouldn't remove the masonite boards, as they're quite even and hard (flat and nice). However, I would take down Tretex because they're too soft for plasterboard and it becomes troublesome to mount anything heavy (such as wall shelves) on the wall since the board risks breaking due to insufficient support underneath. So if you have masonite left on a few complete walls, leave them up (it's difficult to stop in the middle of a wall without it showing through the plasterboard...)
I suggest starting with 6mm in one room so you get a feel for it.
I would go with 6mm boards as they are much tougher and more moldable against the existing wall. They're also quite nice to work with since the flexibility is okay.
Alternatively, you could install type 28x70 battens first and then OSB+13mm plasterboard. But this involves much more work and takes up space. Plus, it feels unnecessary since OSB is meant for mounting things, which your existing walls can handle just fine.
I wouldn't remove the masonite boards, as they're quite even and hard (flat and nice). However, I would take down Tretex because they're too soft for plasterboard and it becomes troublesome to mount anything heavy (such as wall shelves) on the wall since the board risks breaking due to insufficient support underneath. So if you have masonite left on a few complete walls, leave them up (it's difficult to stop in the middle of a wall without it showing through the plasterboard...)
I suggest starting with 6mm in one room so you get a feel for it.
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however, 13 is better in sound-deadening propertiescecar33 said: