Member
· Västra götaland
· 335 posts
We have received the requirement for our garage that it must be fire-rated on one long side facing the neighbor with EI30 now that we've converted from a flat to a sloped roof. Does anyone know what is required to meet this at the eaves? It needs to be a non-ventilated or so-called closed eave to reduce the risk of flames reaching the attic too quickly. Is it enough with something like plywood or exterior gypsum board on the upper part of the wall, or is more needed? I was planning for the paneling to end just below the rafters and have a flat ceiling. Grateful for answers. J
Member
· Västra götaland
· 335 posts
Yes, I will have that.
I have not started on the wall yet, so I'm considering whether to cover it with plasterboard, but if it's not needed, it feels unnecessary.
What I was contemplating is precisely the section between the rafters. Currently, I have mold stoppers a bit up in the roof deck and was planning to put hardboard to prevent the insulation from touching the roof deck. In that case, there is no insulation, so what is required to fulfill EI30? Or should I simply insulate all the way up to the roof deck with the required thickness of insulation (probably around 90mm), or can I put plasterboard on the outside instead? But maybe just 2 layers of plasterboard do not fulfill EI30?
I have not started on the wall yet, so I'm considering whether to cover it with plasterboard, but if it's not needed, it feels unnecessary.
What I was contemplating is precisely the section between the rafters. Currently, I have mold stoppers a bit up in the roof deck and was planning to put hardboard to prevent the insulation from touching the roof deck. In that case, there is no insulation, so what is required to fulfill EI30? Or should I simply insulate all the way up to the roof deck with the required thickness of insulation (probably around 90mm), or can I put plasterboard on the outside instead? But maybe just 2 layers of plasterboard do not fulfill EI30?
Gypsum is a requirement, at http://gyproc.se/ you can read more.
Member
· Västra götaland
· 335 posts
What do you mean by Gypsum is a requirement? On the outside do you mean??
No on the inside. Built a similar garage a number of years ago. Back then, one plywood and 13 mm plasterboard against the inside of the outer roof was sufficient to meet EI30. But check with the municipality if that's still enough. However, if you are going to plaster the ceiling, add 95mm insulation on it, and that should be sufficient.
Member
· Västra götaland
· 335 posts
Yes, I have concluded that if I install as you suggested: 13mm gypsum board, 1 OSB board, at least 95mm rock wool, it meets EI30. But in my case, the small problem is that the garage already has a flat roof, and we have built a sloping roof on top of it, which means there is a space above that needs to be fire-rated. So it is not possible to extend the gypsum all the way to the sheathing from inside.
I am considering whether it is possible to just attach a gypsum board on the outside that is only about 50 cm high that connects to the sheathing, and then lay rock wool tightly against it in the attic. However, I have the downside that it will be directly against the sheathing, but if one wants to achieve EI30 with a closed eave, the insulation must be against the sheathing, otherwise, it serves no purpose??
Mold stoppers are installed about 25 cm inside the outer wall, so the roof above becomes ventilated. Anyone with experience or tips on this?
I am considering whether it is possible to just attach a gypsum board on the outside that is only about 50 cm high that connects to the sheathing, and then lay rock wool tightly against it in the attic. However, I have the downside that it will be directly against the sheathing, but if one wants to achieve EI30 with a closed eave, the insulation must be against the sheathing, otherwise, it serves no purpose??
Mold stoppers are installed about 25 cm inside the outer wall, so the roof above becomes ventilated. Anyone with experience or tips on this?
Member
· Västra götaland
· 335 posts
Read that wood is destroyed at a rate of 1mm/min. That should mean you can place a plank that is 30mm thick between the rafters so ei 30 is met!?
Why do you need to fire rate that space? If the garage itself is EI30 rated, it forms a fire compartment. Usually, there's no need to fire rate an attic space if it's not being used. Because you already have an insulated gypsum inner ceiling?
Member
· Västra götaland
· 335 posts
No, the fire rating applies to the entire wall, both from inside the room and outside. But I will attach a sheet of outdoor gypsum board to the sheathing and then 170mm of insulation as a "fire wall" along the eaves. Easily meets ei30. However, a window seems to be far too expensive to install along the side, a ei30 rated door will have to suffice.