Fire Blocking (Fire Stopping) a tub in a Vancouver multi family apartment building
One of the hardest things to get right is the fire stopping on your new bathroom renovation project. I've seen all sorts of crazy things done but the best approach is to talk to the pros. For me here in Vancouver that's the folks down at Hilti. The Hilti boys have page after page of options and they cover all types of setups. There is no one step maneuver and often it is not so easy to fire stop a job properly.
On this renovation we are fire stopping the trough hole from the bath tub location. It was a large hole and much bigger than ones I've done in the past. I went down to Hilti and discussed the job at hand and left with some fireproof chalking and mineral wool.
The spec sheet requires a 4" layer of mineral wool and a 1/2" of fire stopping chaulking.
Here is how we installed it.
I have never failed a fire blocking (stopping) inspection in Vancouver and owe a huge thank you to the staff at Hilti for being so patent with me and all my questions.
The ceiling of the next apartment. Notice how the waste line is copper. With high rise work the piping needs to be copper or cast through the hole. Once outside this through hole and above the PTrap the code is less strict. The plumber rigged this set up for a new free standing tub.
The mineral wool from hilt is nice to work with but itchy. It comes with dovetail joints and it's required to use 4". I used an extra layer and cross hatched the pieces going in.
Three tubes would have given me about 10% more product than necessary but to be safe I used a whole extra tube to ensure the coverage was correct everywhere.
Vancouver high rise - fire blocking for the bathtub
The chaulking is available in single units but the mineral wool you need to buy a large box. One box will do about 4-6 tub's if they where the size of the one I show above.
Fire blocking is something you need to arrange yourself and have inspected. A final inspection can be failed if this step is not done or the wrong products used. Make sure your tile man, plumber or Handy Andy understand that you require this process.
UL/cUL System No. C-AJ-8143 Hilti Vancouver drawing number CAJ 8143b
And another 10 or 20 options as well. This system is good for huge holes if need be, up to 48"x30" the hole I was addressing was like 8" x 14". Light weight mortars are safer to install when there is no finished ceiling below, I find. This was my first time with this approach as normally I use the Hilti Brick or Fire Brick. I was in and out of the job yesterday in 45 minutes. And that was with a little chit chat with the tile setters.
Originally Posted by dlarrivee
Once an approved system is selected ask your Hilti rep to print off a copy for your inspector. I had two printed so I could keep one with me and leave one on site. Every fire blocking job will be different - so check with a pro each time. Hilti not only tracks my jobs but keeps them on file. I can simply remember what address I at last and say things like "The set up is like what we did on Cornwall, last year." Easy Peasy.
Here is a copy of the Hilti CAJ 8143b drawing (three pages in total) this detail or drawing is UL/cUL System No. C-AJ-8143 MULTIPLE PENETRATIONS THROUGH CONCRETE FLOOR/WALL OR BLOCK WALL F-RATING = 2 HR.
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Options in fire blocking or fire stopping
A couple of my other favourites for fire stopping in Vancouver.
SPray Foam designed for fire stopping.
You can see in this picture that we snuck in the fire blocking with the straw applicator on the spray foam can. We had no access from below and needed to work from above. I weighed down the drain top while things set up.
And the Fire Brick. The brick is my favourite but also the most expensive option.