The drawings I have show the detached garage, unheated, with a slope in the floor that goes from zero at the back wall to -2 1/2″ at the garage doors. No floor drain. We are building in the north country, lots of snow. Any comments? My foundation guy says the slush will melt and run to the doors and perhaps freeze them shut.
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Replies
Gene,
I have poured several floors in the manner you described without a complaint. However I agree that the door freezing shut could be a possibility if the garage is to be heated. That said, I 'll give you another option which is the one I use the most (95% of the time). Place a drain in the center of the floor area to be occupied by vehicles. This area is normally about 24' x 24'. I say this because you implied that you are building a 2.5 car garage and may desire to keep one end flat for benches etc. You need to slope the floor about 2 to 2.5 inches from the walls to the drain which will give you more than adequate fall for drainage. This is a nice setup for melting snow and or washing the car indoors. In most areas the drain can be tied into the downspout lines but check your local code.
Mark
Prof...... I agree with your drain, but theirs allways some guy comes along and tells you his own experience. ( sometimes you wish he would keep them to himself) Last summer an old customer ask if I would plug a garage floor drain for him , said sure and how come, customer said new insurance company inspection said potential hazard for accumuilating dangerous fluids from vehicles. Christmas eve and were talking about floor drains " how bad have we got it "
Nails,
Leave it to an insurance man to come up with something stupid. On a serious note the problem he mentioned can be avoided by using a belltrap style drain which will prevent most of those problems other than straight liquids. As for Christmas eve my wife's watching TV and my 4 year old son just fell asleep on my chest. Needed to take a leak so I laid him down on the couch. Afterwards I decided to see what was going on here on the forum. Going to my folks place tomorrow for dinner. Have a great day.
Mark
we ran into the same drain issue about dangerous fluids.. but we've always used 3" pitch from back to front with a roll from side to side.. keep it straight at the doors so you don't need a weird looking scribe..
never had a problem with doors freezing shut from INTERIOR melt...Mike Smith Rhode Island : Design / Build / Repair / Restore
Didn't JLC do an article or sidebar on this very issue a few months ago. Doors freezing shut was mentioned as a reason to have centered floor drain. Like you Mike, I have never experience that problem, but I am much futher south than you. One question I have about a center floor drain, is how deep do you have to take it? Below frost line, I would guess, but if it is not running to a storm sewer, then what? My last home was on a flat lot, and no storm sewers were available. With a 30 inch frost line, I think I would have been somewhere near the middle of the block before I reached daylight. Twenty years of draining out the front and I never had the door freeze shut.
Dave
guys,
most fuels are heavier than air and lighter than water thus they will pool in a drain. It's simply not very safe. As for a garage door freezing shut, that could only happen when the freeze point is behind the door. Since the garge is heated snow will melt and run under the door seal.
Here in Minnesota it is against code to put a drain in a garage floor.
remember the old gas stations with the mechanic's pit.. before lifts ?..
thye were always full of bad liquids and heavy fumes....
Mike Smith Rhode Island : Design / Build / Repair / Restore
I don't like floor drains in garages. I've never see one yet where the WHOLE floor sloped towards the drain. Seems like there's always a low spot about 5 or 6 feet away from the drain where puddles form.
I'd go for the sloped floor, and slope it as much as you can stand. My garage floor only slopes 3", and there is a low spot right where I get out of the car. It freezes in the winter so I have to get out onto a sheet of ice.
History teaches us that men and nations behave wisely once they have exhausted all other alternatives. [Abba Eban]