How to Build an Attached Carport

With adequate height under the eaves of your home, an attached carport is fairly easy to construct. 

Tools and Materials List

  • Hammer
  • Nail Gun (Rent)
  • 6' ladder
  • Circular saw
  • saw horses 
  • 4' level
  • Extension cord
  • Drill
  • Post hole diggers
  • 4' x 4' x 10' Pressure Treated pine for support posts
  • 2" x 8" x 12' Yellow Pine for headers
  • 2" x 6" x 16' Yellow Pine for joists
  • 2" x 6" x 12' Yellow Pine for front beams
  • 2" x 8" x 16' Yellow Pine for end beams
  • 2" x 6" x 3' Yellow Pine for front braces
  • 2" x 4" x 16' Yellow Pine for rafters 
  • 2" x 4" x 12' Yellow Pine for side braces
  • 4 x 8 x 1/2" plywood for roof decking
  • 1 x 6 x 16" pressure treated pine 
  • Metal roofing material
  • 16d nails for nail gun
  • Felt paper nails
  • Roofing nails
  • Lag screws
  • Metal joist hangers
  • Rafter ties

Step 1 - Check with Your Local Government for Required Permits

Building a carport without a permit is illegal in many areas of the country. Fines could be levied or worse, they could force you to remove anything you've built until a permit is obtained. If a permit is required ask what documents you'll need to produce. Blueprints and site plans are common for this process. 

Step 2 - Lay Out Your Carport

Use stakes and string lines to locate front, end, sides and where the support posts will be. Ensure your layout is square with the existing building before you begin. 

Step 3 - Anchor the Support Header

Use lag screws to attach the support header to the existing building 1/2", plus the thickness of any siding and trim, from the building's edge.

Step 4 - Dig Your Post Holes and Set Your 4 x 4 Support Posts

Using post hole diggers dig the holes for your posts. Insure the posts are level and plumb then use quick set concrete to anchor them into the ground. Use 2 x 4 braces to support the posts as the concrete cures. 

Step 5 - Install the Two End Boards (Outer Rafters)

Use joist hangers to anchor the outer rafters to the support header on one end and lag screws to the 4 x 4 post at the other. Do this for both ends. 

Step 6 - Install the Front Beams

Install the front beams, one on either side of the 4 x 4 posts, along the front (i.e., the long side of the carport) using 16d nails.

Step 7 - Install the Rafters

Using joist hangers to anchor the rafters to the support header and rafter ties to secure them to the front beams install the rafters 24" on center.

Step 8 - Tee Nail 2 x 4 Blocking between the Rafters

Cut then tee nail blocking between the rafters on 24" centers

Step 9 - Cut and Attach Corner Bracing at Each 4 x 4 Post

Attach corner braces at 450 angles to anchor each 4 x 4 post to the end or front beams (depending on the 4 x 4 post location) using 16d nails. 

Step 10 - Final Touches

Install the fascia and metal roofing. Paint or trim the fascia with siding. Pour concrete or spread gravel for the carport's floor.