I am going to build a bathroom. One short side will be 5 mm away from a brick chimney and the other short side is an exterior wall. The short side against the chimney is built with 70 metal studs, 15 mm structural plywood, and then plasterboard. The long sides are built in the same way but with wooden studs 45x70 mm. Plasterboards are placed on the outside of the long sides against the chimney, thus enclosing the short side.
Since I am not enclosing the "backside" of the wall against the chimney, I choose cc30 instead of cc45. All to make the wall more stable.
I am thinking of putting grilles at the bottom and top of the short side wall so that the air can circulate. The smallest refrigerator grilles require an opening of 45 mm x 370 mm. Can such an opening in a metal stud cause problems? The opening is made in the wall's first and last stud (upper and lower on the opposite side)
Comments on the placement of panel material and studs?
You should be able to do as you planned and it's good to use cc30 on the steel studs. However, the question is whether it would have been possible to run wood directly against the chimney. How hot does it get?
It's the chimney sweep who says I can't have anything combustible against the chimney. However, it was okay for me to bring the gypsum board forward so that it goes against the outer edge of the chimney.
Is the chimney sweeper okay with you building a non-inspectable space by putting up a wall against the chimney? I failed the fire safety inspection for this and had to drill holes in the drywall.
Asked specifically about the inspection possibility
(remember that you have mentioned it before)
The chimney sweep replied that it wasn't necessary since the tightness is checked from above. Additionally, my smoke pipes were on the other side of the vent pipe, which is the closest pipe to the new bathroom wall.
