Can perforated tape replace exterior gypsum for stiffness?

[Anders_Nilsson]

Considering the idea of an outer wall with three layers of insulation. Assume horizontal 45+vapour barrier + vertical 120+ horizontal 45 from inside to outside (intended for a garage). If you start by building the stud wall with 45x120 and attach metal straps in a cross pattern with anchor nails, will it be rigid enough to just install horizontal 45s with insulation on the outside and then a weather membrane on top, followed by horizontal 45s on the inside with insulation, OSB, and plasterboard on the inside? Or are additional cross braces needed in certain stud spaces? If so, how many braces, one for every five stud spaces?

The garage has no windows, so I was thinking of a large cross over the entire width. Where the door is located, I thought as large crosses as possible over the wall. If there were windows, the metal straps should be tensioned over as many spaces as possible.

Or should one skip the metal straps and inset a 28x70 or similar diagonally across the entire wall width? Or is it better with cross braces inside the stud spaces?

/Anders

 

[mycke_nu]

It seems a bit silly to come up with your own methods when there are tried and true ones that are both simple and cheap.

 

[Mikael_L]

Thinking about this with an exterior wall with three layers of insulation. Assume horizontal 45+vapor barrier + vertical 120+ horizontal 45 from inside to out (it is meant for a garage). If you start by building the wall frame with 45x120 and attach perforated straps in a cross pattern with anchor nails, is it then rigid enough to simply put horizontal 45s with insulation on the outside, then wind paper outside this, and then horizontal 45s on the inside with insulation, OSB, and drywall on the inside?

That's excellent. I think you don't even need the perforated straps, but if you want to sacrifice a few meters of straps, it will brace the frame even better.

Tightly fasten the perforated straps in a cross about 45° or flatter, meaning the width of the cross can be something between 2.5 meters and a bit longer (at 2.5 meters ceiling height), but you shouldn't make the cross over 4 meters wide because it reduces the tension holding of the perforated straps more and more then. Screw in each vertical stud where the strap passes. Then nail the horizontal 45s on both sides with 100mm galvanized nails and finally OSB on the inside of the frame structure for a very stable frame.

Just don't forget to plumb all the walls properly during construction and nail temporary bracing like, for example, wood board, which you don't remove until the OSB is in place. You can, for example, place two braces on a long wall and then remove one at a time as you finish the wall.

edit: The text: "which you don't remove until the OSB is in place" in my last paragraph might not be so important if you have already installed the perforated straps; the straps should hold everything straight until you have the interior wallboards in place. At least unless the storm Gudrun's cousin happens to pass by.

 

[Ola78]

Thinking about the idea of an outer wall with three layers of insulation. Imagine horizontal 45+vapor barrier + vertical 120+ horizontal 45 from inside out (should be for a garage). If you start by building the stud wall with 45x120 and place perforated straps in a cross with anchor nails, will it be stiff enough that you can just place horizontal 45s with insulation on the outside and then wind barrier on top of that, and then horizontal 45s on the inside with insulation, OSB, and gypsum on the inside? Or are cross braces required in some stud bays as well? How many braces then, one per five stud bays?

The garage has no windows, so I was thinking of a large cross over the entire width. Where you have the door, I was thinking of as large a cross as possible over the wall. If there were windows, one would tighten the perforated straps over as many bays as possible.

Or should one skip the perforated straps and inset a 28x70 or similar diagonally across the entire width of the wall? Or is it better with cross braces that stand inside the stud bays?

/Anders

It's a well-proven solution. We use it on garage walls we manufacture that don't have any interior paneling to stiffen them up. It usually involves a cross over the entire length of the wall and in case of openings, crosses on both sides of the opening.

Edit: Just saw that Mikael_L beat me with the same answer. He's a quick one at responding, that guy

 

[Anders_Nilsson]

Thanks for the answers!

I checked Isover and Paroc but they don't show how to reinforce the wall, only the insulation principle. On the träguiden, I didn't find a three-layer wall. One can of course use exterior gypsum between the standing studs and the outer layer, but recently there seems to be a belief spreading here on the forum that exterior gypsum is mold-sensitive.

I plan to start by raising the gable on the back of the garage, then build the sidewalls as frames on the slab, making it easy to measure diagonally and add sufficient reinforcements while the frames are lying down. A bit like prefab but manufactured on site.

/Anders

 

[Mikael_L]

then build the side walls as frames on the slab, then it's easy to measure diagonals and then put in sufficient reinforcements while the frames are lying down.

That's true, but once the wall is up, you may have to let it be slightly skewed (i.e., not equal in the diagonals) so that it becomes vertical instead.

I built exactly as you describe, but I didn't align things until they were in place.

But you can secure a diagonal brace before raising it, so it doesn't give way then.