Driveway Layout

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Chucktown PE

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I am trying to do a site layout for a house I'm hoping to build. The house will be elevated with the garages underneath the house. However, I'm concerned that I don't have enough room on the site such that I can make a 90 degree turn from the driveway into the garage underneath the house. On this layout the property lines are the thick green and the driveway is the narrow green. What are the minimum dimensions that I need to comfortably get the cars in the garage (i.e. so my wife isn't knocking the trim off of the garage doors)?

Site_Layout.pdf

 

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question: Why are you letting your wife drive in the first place?

 
That's what girlfriends are for, not wives.

 
My driveway also has a 90 degree turn at the top like yours, going into a 2 car garage, with two 9' wide garage doors. The distance perpendicular from the garage door to the side of the driveway is 30'. Mrs S. is in the first stall and I am in the second. She has a Toyota Sienna and she has hit the garage several times pulling in. I can pull her car in, but you have to almost drive off the side of the driveway and turn at the perfect spot going very slow. I can not pull in straight until the vehicle is a couple feet inside the garage. At least for this size vehicle, I don't think we could have gone much less than 30' and still make a one shot turn.

 
Is the driveway going to slope down for your garage under? This tends to act as a funnel drawing rain and runoff into the garage. Make sure the place is graded so this doesn't happen. You can add a drain, some stormwater retention, and a sump pump but, it's a situation I'd prefer to stay away from.

just sayin'

 
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My driveway also has a 90 degree turn at the top like yours, going into a 2 car garage, with two 9' wide garage doors. The distance perpendicular from the garage door to the side of the driveway is 30'. Mrs S. is in the first stall and I am in the second. She has a Toyota Sienna and she has hit the garage several times pulling in. I can pull her car in, but you have to almost drive off the side of the driveway and turn at the perfect spot going very slow. I can not pull in straight until the vehicle is a couple feet inside the garage. At least for this size vehicle, I don't think we could have gone much less than 30' and still make a one shot turn.

Glad I asked. I read some suggestions on the interwebz that said 17' was an acceptable outside turning radius. You're telling me 30'. Mrs. Chuck is going to be in the second stall and I'm going to put my boat in the first. But I'm going to rig up a winch system to pull the boat trailer into the garage so I don't have to back it in.

 
most vehicles are typ in the 40' range for turning radius (180 turn), maybe 25'ish would be minimum I'd consider (depending on vehicle). there's always the 3 pt(+) turn :joke: - make sure the smallest vehicle gets the front stall. Straighten out the driveway on the front end (square it with the way the house sits).

Does this lot slope from front to back? Are there setbacks for driveways / paved surfaces?

 
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Factor this in. The AVERAGE car has a 32-34' turning radius. This is for a U-turn, so actual radius if drawing a circle would be 16 to 17 feet. This is if you have the wheel at full lock with absolutely no margin for error. I wouldn't trust a 17' outside radius to park a bicycle, never mind a full sized vehicle or SUV. I could MAYBE see 17' as an acceptable inside turning radius at best.

 
I just double checked on Google Earth and I am getting closer to 20'. My drawing is probably wrong.

I will measure it tonight and let you know.

 
I would try and go parallel the property line as far as you can to give you a little more seperation (& room) for the turning radius, but I think most people should be able to handle that turn, but the important feature will be backing out

 
most vehicles are typ in the 40' range for turning radius (180 turn), maybe 25'ish would be minimum I'd consider (depending on vehicle). there's always the 3 pt(+) turn :joke: - make sure the smallest vehicle gets the front stall. Straighten out the driveway on the front end (square it with the way the house sits).
Does this lot slope from front to back? Are there setbacks for driveways / paved surfaces?
Thanks for the advice. The lot will slope from front to back. Long story but the lot sits in the AE flood zone w/ base flood elevation of 14. Grade is about 7. So I'm going to bring in a couple of feet of dirt in the front so I don't have 10 feet of stairs to climb in the front of the house and it will make the house appear lower for aesthetic purposes.

Factor this in. The AVERAGE car has a 32-34' turning radius. This is for a U-turn, so actual radius if drawing a circle would be 16 to 17 feet. This is if you have the wheel at full lock with absolutely no margin for error. I wouldn't trust a 17' outside radius to park a bicycle, never mind a full sized vehicle or SUV. I could MAYBE see 17' as an acceptable inside turning radius at best.
I can probably go to 20' but what I haven't shown on the layout is the 5' setback line, which I'm already encroaching on with the 17'.

I just double checked on Google Earth and I am getting closer to 20'. My drawing is probably wrong.
I will measure it tonight and let you know.
Thanks for the help.

I would try and go parallel the property line as far as you can to give you a little more seperation (& room) for the turning radius, but I think most people should be able to handle that turn, but the important feature will be backing out

RG, there's a 5' setback on the property line so that's the reason I had to make it angle the way it does. I'm looking to see if I can build the driveway in the setback. If I can that will give me some more room.

 
in our area local governments dont consider the driveway as part of the setback, but of course that will be different from place to place

 
Well I was way off, I guess I never updated the design drawings to the as built drawings (figures)!

I have 23' wide at the first stall. There is a bush that cuts off about 1' of clearance, so call it 22'. I think I would be able to get into the garage at 17' wide in one shot into the second stall with my Trailblazer. But I don't think I would be able to back out of the garage, turn and be able to drive forward out of the driveway at 17' wide in one shot, unless you extend the driveway past the second stall. In hindsight I wish I did extend past the second stall since then you can have a car in the driveway and still have vehicle access to the garage.

 
Parking lot layout might give you the answers you need. Typical "aisle width" for entering and leaving 90-degree oriented parking spaces is 24 feet. That accommodates 2-way traffic, so you could probably get away with less, but 24 feet would provide more than enough space to make the turn safely.

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