To slope or not to slope

[swharris]

So my contractor asks me yesterday if I'm ok with a 2% slope to the main door, or do I want it flat? I have absolutely no idea. My inclination is to make it flat. WWGJ do?

For some background, this is a 50x40(aprox) space with a main two & 1/2 bay work area and a Machine area off to the side. Unfortunately, my property has **** for slope and we are having issues with enough drop for a proper drain pitch. We are still juggling things in hopes of being able to put in a drain, but if not, should I have the work area sloped (slightly) to wards the main door or will it be enough to just be able to squeegee the water out if it gets in there.

I'm in Southern CA, and despite the crazy deluge from the last two weeks, it mostly never rains here. I don't see washing things inside if I don't have a drain, but it would be a nice thing to have, so I'm shooting for that.

This drawing is close but not completely accurate. The apartment now encroaches into the garage space forcing a move of the bathroom and some of the machine area. It's close to what we will build.

 

[acer66]

If my memory serves me right someone posted in another thread that there is a code requiring a slope when a garage is attached which looks like yours is.

 

[The Tool Tyrant]

FLAT, FLAT, FLAT! fyi, there is no code for sloping a garage slab in California unless it was just changed.

You'll be kicking yourself in the **** if you slope it and have anything on wheels. If you fabricate, a flat floor is an added bonus. Sitting up equipment is so much easier on a flat surface. No good justification for sloping unless you're starting a car wash in your shop!

FYI, you may want to add a door for your poor assistant to access their dungeon...and I'm sure they would appreciate at least 1 window!

 

[Marcm157]

I did a 36 deep garage with a slope and I'm sorry I did. Slope is 2‰ nothing really drains towards the doors. The only real water on the floor is rain / snow that drips or melts. The floor is sloped enough though that if I get out and leave it in neutral to raise it on the lift it will roll back. It's also enough to make my tool boxes and workbench ust a bit uneven.

If I had it to do over again it would most definitely go flat...

 

[Absentglare]

No slope. Drainage should be sufficient with roofing and gutters. I can think of all kinds of advantages to having no slope and no real advantage to having the slope.

 

[txvwnut]

I'm with the flat consensus. The guy that did my pour slopped the first 12" of the floor, that way the driveway could be just a bit lower than the pad and decrease the chance for rain water to flow into the shop.

 

[acer66]

Just in case this might apply.
Not sure how to post this so a link has to do for now.

http://www.garagejournal.com/forum/showpost.php?p=6232360&postcount=7

 

[Randy in Maine]

Flat in the building and a 2% slope from the garage doors down to the street.

 

[larry_g]

My walls are FLAT and plumb. Flat and LEVEL is what you want. It seems that you are making a workshop vs a parking garage. If just a parking garage then slope is appropriate but a workshop, in my opinion, should be flat and level. If you want it flat then you should have a flatness spec such as no more than 1/8" variance in any 10'. If you want a smooth finish then spec that out also.

lg
no neat sig line

 

[James-W]

My walls are FLAT and plumb. Flat and LEVEL is what you want. It seems that you are making a workshop vs a parking garage. If just a parking garage then slope is appropriate but a workshop, in my opinion, should be flat and level. If you want it flat then you should have a flatness spec such as no more than 1/8" variance in any 10'. If you want a smooth finish then spec that out also.

lg
no neat sig line

I have a detached 24X36 garage and it is flat until you get right under the overhead door, then the approach is sloped away from the building and down the driveway. But to be fair, I don't park cars in the garage, I use it as a workshop so I don't get water on the garage floor unless I am mopping the floor. Even then I don't take the mop and slop a bunch of water on the floor, I use a mop pail with a wringer on it and I wring out the mop so it is wet, but not dripping water all over the place.

 

[The Tool Tyrant]

I forgot to mention, IF you are pouring an approach or driveway abutting the garage slab, have your contractor stop the garage slab at the INSIDE of the stem wall. This will allow you to do two things, first, slope the approach/ driveway to the face of the garage door and secondly, if you are doing colored and /or stamped concrete on the approach / driveway, it will be continuous to the door. If you don't, and run the garage slab to the outside face of the stem wall, then you will have the width of the stem wall in grey concrete abbuting the color/ stamp concrete.
It's doesn't seem like a big deal, but it makes a big difference in the finish product.

 

[swharris]

Thank you all for your opinions! Flat it is. I doubt it will be within 1/8 in 10, but they assured me they will make it flat and smooth as possible.

ToolFool: The entrance is to an ally, so there is no formal approach to worry about. I am concerned about sealing at the bottom door edge. Would making the seam at the inside of the stem wall cause a joint to be right where the door comes down to meet the concrete causing possible sealing issues? Hard to visualize.

 

[swharris]

FLAT, FLAT, FLAT! fyi, there is no code for sloping a garage slab in California unless it was just changed.

You'll be kicking yourself in the **** if you slope it and have anything on wheels. If you fabricate, a flat floor is an added bonus. Sitting up equipment is so much easier on a flat surface. No good justification for sloping unless you're starting a car wash in your shop!

FYI, you may want to add a door for your poor assistant to access their dungeon...and I'm sure they would appreciate at least 1 window!

That is just a place holder box. I have not drawn it out to scale yet. It's actually a 1 bedroom apartment/mother-in-law/PCA quarters. It's for the future if my mom gets too old to live on her own or for a full time care assistant for my wife(C6 quadriplegic from MVA in '06) if/when I get too old to help her. For for the short term(10-15 years) it will be an income property. Have to help pay for this taj mahal somehow. Haha.

 

[rburke65]

Flat.....like the earth......

 

[dw1]

my barn is 30x50 (30' deep), it has a 1 1/2" drop towards the O.H doors, I don't think it made any difference what so ever, but my buddy suggested it, so I did it. Now for the apron, I had it formed up and the concrete guys changed it, my 4' apron has a 5" fall out the doors. I have never had any water infiltration issues. My buddy is a GC and I used his concrete guys, they were not concerned about the fall/slope of the pad and like I said, I don't think you can tell it made any difference, I'm glad they changed the slope of the apron.

 

[acer66]

Flat.....like the earth......

 

[dutchgray]

Flat with a slight slope for the last couple feet at the door, so any water that blows in will drain out or not spread everywhere. If you really want put an ACO drain along the door inside to get any water.

 

[lakeroadster]

Thank you all for your opinions! Flat it is.

Good call. On my shop we left the floor flat except for about 5 feet from the overhead doors, and then sloped the concrete to direct any water out the doors.

They also made the slope more significant right where the overhead door meets the concrete.... but not a pocket.

Good luck on your project.

 

[The Tool Tyrant]

Thank you all for your opinions! Flat it is. I doubt it will be within 1/8 in 10, but they assured me they will make it flat and smooth as possible.

ToolFool: The entrance is to an ally, so there is no formal approach to worry about. I am concerned about sealing at the bottom door edge. Would making the seam at the inside of the stem wall cause a joint to be right where the door comes down to meet the concrete causing possible sealing issues? Hard to visualize.

Not at all, (I'm assuming you're using a sectional style door) the gasket on the door bottom will be on the garage slab and the gasket flap that extends outward from the door covers the joint.

That is just a place holder box. I have not drawn it out to scale yet. It's actually a 1 bedroom apartment/mother-in-law/PCA quarters. It's for the future if my mom gets too old to live on her own or for a full time care assistant for my wife(C6 quadriplegic from MVA in '06) if/when I get too old to help her. For for the short term(10-15 years) it will be an income property. Have to help pay for this taj mahal somehow. Haha.

Ironic, my business is fabricating custom sports wheelchairs, specifically for the sport of quad rugby, also known as wheelchair rugby.

 

[Ch3No2]

Flat! I did mine flat and where the 6" stem wall is at the door I sloped it 1/4" to keep outside water from coming in and am very pleased.

 

[CNGsaves]

+1 for FLAT.

For the garage door, I'd have the concrete guys "finish" that edge with a step-down notch for garage door to seal. See other GJ pics as it's great to keep leaves and dirt from blowing in garage.

Don't leave it up to them to decide. YOU decide exactly what you want, and . .
. . . PUT IN WRITING . . . so they have to Do It Like YOU Want It !!

 

[roblouvasz]

I've never had a garage built or a slab poured. That being said, the house we bought had a 3 1/2 car garage with drains. The floor is sloped to the drains and the drains exit out the foundation out the back. Apparently it's OK in my area. There was a permit pulled. I never understood why someone would build a garage without drains. So, I would be sloping the floor and installing drains. Just my 0.02 cents.

 

[swharris]

Not at all, (I'm assuming you're using a sectional style door) the gasket on the door bottom will be on the garage slab and the gasket flap that extends outward from the door covers the joint.

Ironic, my business is fabricating custom sports wheelchairs, specifically for the sport of quad rugby, also known as wheelchair rugby.

No. I'll be using a commercial roll up(or similar). I want to avoid the overhead light blocking of a traditional segmented door when it's in the up position. That said, I've started costing out a 20+ foot commercial door...yikes!.

Quad rugby. Wow. Had no idea that existed. That's really cool about your business. Sadly, she refuses to get back in a manual chair she was in right after she came home from rehab. She has some fear of wearing out her shoulder joints. I think it would be good for her. You can not make someone do something no matter how much you care.

 

[The Tool Tyrant]

No. I'll be using a commercial roll up(or similar). I want to avoid the overhead light blocking of a traditional segmented door when it's in the up position. That said, I've started costing out a 20+ foot commercial door...yikes!.

Ya, tell me about it! We have a 12' on our shop and when I checked on the cost for an opener, I said...the manual is fine.
The way that the roll-up track mounts is basically the same as a sectional so you won't have a seal issue.

Quad rugby. Wow. Had no idea that existed. That's really cool about your business. Sadly, she refuses to get back in a manual chair she was in right after she came home from rehab. She has some fear of wearing out her shoulder joints. I think it would be good for her. You can not make someone do something no matter how much you care.

Here is the link to some of the 2016 Paralympic's Gold Medal Match between USA and Australia. All the chairs with red spoke guards are built by us.

 

[1jjpop]

In Iowa you want a slope , because you drive your car in the garage with snow on it , it melts . Makes A mess..Also another thing , when you pour your floor put some 3' long rebar where the floor mets the drive way , [ so your driveway don't settle ]In our town they didn't do that , the driveway settles makes a bump going into garage.