[Ptax]

We would like to build a 12 x 16 carport over an existing concrete driveway. The driveway is MANY years old and has a layer of asphalt over the top. The carport is designed with a gabled roof.

My concern is this. The design calls for the posts (4 on each side and one in the middle on the back side) to be set in a galvanized bracket which will be secured with 24" spikes driven through the drive into the ground. (I am assuming that holes would be drilled through the concrete.) Will this be enough to secure the carport even after years of shaking and moving due to wind?

If not, what other options should I consider to secure the carport to the drive?

 

[oh'mike]

That doesn't sound very strong----I think concrete piers --dig below the frost line would be the correct way to do it----Could you post a sketch?

Will this be attached to the house?

 

[GBrackins]

12'x16' carport .... what do you drive, that's seems small. Where do you live?

 

[Ptax]

securing a carport

I drive a Subaru Forester. Live in SW MO. See pic for basic design.

I really appreciate the feedback.

 

[joecaption]

No way should it just be standing sitting on top of a slab or driveway.
Going to need footings.

 

[GBrackins]

I'd recommend checking with your building department to determine what your footing/foundation requirements are. You may have a minimum frost depth (depth below ground so that cold weather does not affect foundation). They may also be able to tell or describe to you how these are typically constructed in your area. Building department is always an excellent source of information and guidance (at least in my area). They may be able to let you know if you have any setback issues (required distance from property lines to structures).

I do not know what building code you are under, what your frost depth is if any, what your ground snow load requirement is, or basic wind speed so I can only speak in generalities.

I agree with oh'mike, I'd be using concrete piers set into the ground with a stand-off post base anchored into the pier. I don't know what a pin driven 2-feet into the ground would do to resist wind loads. Around here we'd typically use a 10" or 12" sonotube (round tube that's filled with concrete) set to our frost depth (48" depth in Massachusetts). Size of footing is based upon actual loads and soil bearing capacity.

Stop and think about the construction. Your columns act as a lever. If you want to lift something heavy you can stick a lever over your fulcrum under it and use the mechanical advantage to move the object. A force applied at the top is increased at the bottom. You have to have something to resist these forces. In your case wind blows against the roof (like a sail on a boat). these forces are transferred from the roof through the columns to the ground. If not designed and built properly you'll have issues, and no one wants that for you.

You may want to consider hiring an engineer. If you need a building permit typically you need drawings. The engineer would prepare the construction drawings that would not only get you your permit but explain the proper construction. Doing it correctly the first time what you want so it would be money well spent.

Hope this helps! Good luck!

 

[Ptax]

securing a carport

Greatly appreciate the feedback. It confirmed my worries about the how secure it would be with the spikes only.

 

[md2lgyk]

I do not know what building code you are under, what your frost depth is if any, what your ground snow load requirement is, or basic wind speed so I can only speak in generalities.

Strange state, Missouri. It is entirely possibly there are no residential building codes whatsoever where the OP lives. So there may not BE a building department. My sister-in-law and her husband live a bit North of Kansas City and have been renovating a 1920s farmhouse for the past couple of years. The county they live in has absolutely no building codes or inspection requirements. I have seen the house and, fortunately, they appear to know what they are doing. I saw many things that wouldn't pass code here, such as stair treads not wide enough, but all were minor.