Fire-rated separating wall

[Marcus Nielsen]

When renovating our bathroom in the townhouse, I need to take down the plasterboards on the wall against the neighbor. The wall is naturally a "separating fire wall" and built as the picture below shows. I want to put up 15 mm construction plywood under the new plasterboard in our bathroom. The handler at the housing association's insurance company mentioned that if I place the plywood against the studs and ONE layer of plasterboard on top, the wall is still classified as 60 minutes fire resistance. Could that be correct? All the information I can find says TWO layers of plasterboard when the construction is as shown in the picture.

 

[Åsa Lund]

Take one layer of plywood and two layers of gypsum

 

[Autodidak1]

During the renovation of our bathroom in the townhouse, I need to take down the gypsum layers on the wall towards the neighbor. The wall is naturally a "dividing fire wall" and built as the picture shows below. I want to put up 15 mm construction plywood under the new gypsum layer in our bathroom. The officer from the cooperative housing association's insurance company mentioned that if I place the plywood against the studs and ONE layer of gypsum on top, the wall is still classified as 60 minutes fire resistance. Can that be correct? All the information I can find says TWO layers of gypsum when the construction is as in the picture.

That's correct, you can replace one layer with plywood and retain the fire rating.

 

[Marcus Nielsen]

That's correct, you can replace one layer with plyfa and maintain the fire rating

Thanks! That would be convenient. Do you possibly have a link where this can be confirmed?

 

[Autodidak1]

Thanks! That would be convenient. Do you possibly have a link where it can be confirmed?

It's included in the bible https://www.traguiden.se/om-tra/byg...rakonstruktioner/avskiljande-formaga/exempel/

 

[Marcus Nielsen]

Exists in the Bible [link]

Yes, I checked there earlier and if I understand correctly, I interpret that it must be a 95 mm stud if one layer of gypsum is to suffice for 60 minutes. Or am I misunderstanding? A lot to learn here, I feel

 

[Åsa Lund]

Yes, I checked there earlier and if I understand correctly, I deduce that it must be a 95 mm stud if one layer of gypsum is to be sufficient for 60 minutes. Or am I wrong? There's a lot to learn here I feel

The way I interpret the table, I agree that it should be a 95 mm stud and stone wool in the wall. The question is if the fire rating is also REI60?

 

[tergo]

if you tile from floor to ceiling, it will also increase the fire rating
or 15mm plywood + 15mm fire gypsum

https://www.gyproc.se/produkter/gip...skivor/innerväggsskivor/brandgipsskivor-gf-15

 

[Autodidak1]

Yes, I checked there earlier and if I understand correctly, I deduce that it must be a 95 mm stud if one layer of gypsum is to be enough for 60 min. Or am I misunderstanding? A lot to learn here I feel

You have 2x70 mm studs with an air gap in between, i.e. 140mm studs + 20 mm air.

Then, as Tergo points out, the tiles also improve the fire rating.