I plan on building a free standing carport beside (but not attached TO) my house, on the concrete driveway. I'm looking at 12x24', with custom-built trusses which match the pitch of my house's roof.

I will be using 4x4 or larger square wooden columns on each corner plus one midway down each of the longer sides. The support beams will be double 2x6 or 2x8s on end, and the trusses on top of the beams.

I know there's a wide variety of brackets and hurricane ties for the trusses to sit in and attach to the support beam. But just looking through the Lowes online pages I can't find anything that's specifically designed to attach the support beams to the square columns. I've seen other carports around here where it appears the builder just toenailed the beams to the columns but I would think there is a better way. One online site about retrofitting carports in FL to protect against hurricane damage showed a Tee Strap connecting beam to column. But is there anything else available?

 

It sounds like you probably need a combination of HH4's or RTF2's and RTC44's.

 

Excellent, thanks! I found the HH4 on Home Depot's web site, but had no luck locating the RF2 or -44 :
4x Header Hanger-HH4 at The Home Depot

One question, though....does the HH4 go pn oriented like it is shown in the picture, with the double 2x6 or 2x8 beam sitting in the "saddle", or does the column fit in the saddle and the single strip go on the side of the beam?

 

Yes, the header sits in the saddle. You'd probably put one on each side of your mid-span posts.

 

No expert....but 4x4 sounds pretty small. I would think 4x6 or 6x6 would be more appropriate.

As I understand...always better to rest beams on top of posts or at least in a notch.

 

You may want to consider adding another column in the long direction. A double 2 x 8 beam will tend to sag when spanning 12'. I built a very similar-sized carport at a house in Colorado a few years ago, and I couldn't get anything to economically compute for the 12' spans. So I bought some salvage steel wide-flange beams for less than $100, cambered them with a torch and was able to eliminate both midspan columns--22' clear span. Welded them to the tops of the salvage steel 4 x 4 x 1/4 columns ($20 each) I used, embedded in concrete.

 

"You may want to consider adding another column in the long direction. A double 2 x 8 beam will tend to sag when spanning 12'. "



So exactly how would the long (24') direction columns be spaced? I was thinking of one column on each corner plus one at the halfway point on each long side. Are you suggesting putting an additional two columns on the long sides: one halfway between each corner and the planned midpoint column. That would give a column every 6 feet on the long sides.

Which brings up another question: I was planning on using just 12' long double 2x8s. So the long sides would be made of two 12' double boards butted against two other 12 footers, with the midway post supporting their junction. I've never actually seen 24' long 2x8s....are they available and if so, is it difficult to find straight ones?

 

Three equal spaces at 8' each should get you there. Meaning a total of 4 columns, one at each end and two interior. Build yourself continuous beams using 8' 2 x 8s, glued and screwed, with staggered splice points. The configuration of the doubled beam should be 8-8-8 and 4-8-8-4. It will be as straight as your carpentry skills allow, and far stronger and stiffer than going with 3 equal, simple spans.