The question of obtaining a permit or approval depends on where you live. Some areas require city of township approval as well as inspection and some areas have additional deed restrictions from the HOA. The contractor you hire should be well versed in the type of permitting you need for your area. If not, I suggest you look for another contractor. Your contractor should also ask you for a current copy of your survey in order to check out building lines and easements to ensure the structure does not encroach. Additionally, you'll want to make sure you hire a reputable contractor for quality results!
The above answers are to the point, I would simply like to add that regardless wether you need a permit or not, it is advisable to build it to current code so that when you sale the house it is not flagged as a deficiency by the home inspector. I have seen many DIY patio that looked kind of ok but were not build to code and it was always a strong negociation point after inspection. francois@cozy-homes.com / 713 397 8857
You also need to check your survey for any easements. If your building encroaches the easement, you can look into getting an exception, but I would recommend avoiding building in the easement.
From a form regarding fences, but still same information: You will be required to obtain an exemption from the Office of the City Engineer if your project encroaches on any portion of the street or roadway easement. You will be required to apply for Consent to Easement Encroachment through the Utility Analysis – Developer Services Section if your project encroaches on a City of Houston utility easement. If you have questions regarding this, please contact Sarun Chhin at 832–394–8986.
It will depend on where you live. If you live in an incorporated city, you will need to get a permit from that city. If you live in a subdivision with deed restrictions, you will need to get it approved by the Homeowners Association. If you live in both, you will need both. If you live in an unincorporated area of the county and do not live in a subdivision with deed restrictions, you will probably not need a permit, but I do recommend that you call the county general phone number and ask them for a building permit department to confirm this. I hope this helps you!