Double plasterboard or single plasterboard in the garage ceiling?

[fredand44]

Hi!

I'm in the process of building a garage.
At lunch today, a good friend mentioned that you probably need to have double drywall on the ceiling for the fire insurance to be valid.
I've only put OSB board and "under" that single drywall on the ceiling.
But I am fully able to install double drywall right now since the ceiling hasn't been spackled or painted yet.

Grateful if someone can tell me if it's a rule that you must have double drywall on a garage ceiling for insurance purposes.

Best regards,
Fredrik

 

[Johan Gunverth]

If it's in the basement of a residence, it's just common sense to install double drywall. Attached garage without a finished attic, I don't know. I have double drywall and a sprinkler system in my basement garage. Mostly because it's also a workshop for all sorts of things.

 

[injonil]

Firstly, double boards are not necessary at all; a single one is sufficient according to the Boverket's regulations.

Secondly, you get the same fire rating from OSB + gypsum as from double gypsum, i.e., E60.

 

[Johan Gunverth]

Missed that TS had OSB under the gypsum. Absolutely right.

 

[fredand44]

Hi!
Nice with quick responses!
Thanks!
Best regards,
Fredrik

 

[injonil]

I'm installing OSB + drywall myself in my basement area that will become a garage. The case officer at the municipality recommended double boards but probably knew it wasn't a requirement since he expressed it that way.

 

[bempe]

If the fire has taken hold in a garage, it probably doesn't matter if you have single or double gypsum in the ceiling. I probably wouldn't want a fire-damaged garage to renovate... let the crap burn down instead and build new... I would have needed a fire myself to get rid of all the junk that has been accumulated over the years... hehe The car hasn't been able to be there for a loooong time, unfortunately. Now, of course, I'm talking about detached garages with normal ceiling height and no loft above.

 

[jhenrikj]

If the fire gets a hold in a garage, it probably doesn't matter whether you have single or double gypsum in the ceiling. I probably wouldn't want a fire-damaged garage to renovate... let the stuff burn down instead and build new... I myself would have needed a fire to get rid of all the junk that has accumulated over the years.... haha The car hasn't been able to be in there for a loooong time, unfortunately. Now I'm of course talking about detached garages with normal ceiling height and no loft above.

Now, it’s not the garage you should fireproof but neighboring buildings. The fire rating is to limit spread (gypsum burns poorly). Or do you think that if the garage starts burning, the residential house should just burn down too?

Edit: That is, the fire protection is built in the garage, but not so that it won't burn down.