Painting Porch Columns

[DIYDan]

I plan to build a roof for my front porch that will connect to the steep-pitched roof of my brick cape cod house. I want to use 2 square columns, about 7" or so wide by about 8' tall.

These columns will support beams coming from the house. The beams support the rafters of the porch roof. Since the columns will be load-bearing, I want them to be solid instead of hollow. I was thinking about pressure treated wood.

But I want the columns to be painted white. I don't have experience painting pressure treated wood. I'm thinking it might now work well. Any ideas? Should I cover a center post with better wood for painting?

I would buy the prefab kind of columns with the metal tube down the center but they don't have any plain smooth square columns at Home Depot. I don't want something fancy. Any ideas?

[Edwin Pawlowski]

Go some place other than Home Depot? You local lumber yard may have a better selection. I've seen things like you describe used on TOH or some decorating show.

There are many nice items that you'll never find in the mass market stores.

[no(SPAM)vasys]

Use 4" x 4" pressure treated and box the columns out to get the look you want.

[woodworker88]

I would use the unassembled box colums made of cellular pvc around a metal or pressure treated wood post. The cellular pvc can be shaped, machined, and painted like wood but it doesn't split, warp, crack, or rot. Just make sure that the ones you buy come disassembled because you will need to connect the parts around the inner post. Most come in two sections, each with two sides of the column. Some of the cellular pvc components sold are already factory finished. If you must paint them yourself, I would recommend a two part epoxy paint for extreme durability. Nothing looks worse than high tech composite materials with peeling paint.

[Mike]

Check with the local lumber yards to see what is available. It might depend on the look you are after. You should be able to find

6x6 and 8x8 rough cedar if you don't mind the look. It can be painted. You might be able to have the yard surface it for if you don't want the rough surface. You would still have the knots to contend with. You might also be able to find fir beams. I would prefer a solid post myself. You can easily box in the supporting posts to get the look you are after but I would be concerned that over time the joints might come apart or at least become visible. If the posts were not standing in the weather, I wouldn't be so worried about that.

Mike O.

[Lawrence Wasserman]

PT lumber can be painted but you must wait long enough to ensure that it is dry enough. After treatment the lumber can be really wet and if it is too wet, paint may not adhere. The bigger problem you will face is that the surface of common PT lumber will not be good enough for what you are describing. There will be many checks, cracks, knots, etc. So you probably would want to cover it as you asked, or use a steel post and build a wooden box around it. That is a pretty common approach, BTW.

[Richard Cline]

Much of the presssure treated wood has perforations to aid in absorptiion of the chemicals. These perforations will detract from the appearance of the columns. Of course you can fill the holes but it does entail a lot of extra work. The print will stick to the wood OK -- I have painted numerous posts.

Dick

[DIYDan]

Wow. Six great answers to my original post. This is great. Thank you everybody! I've decided to use 6x6 pressure treated posts, and then box them in with a more paint-able wood. I may use construction adhesive and a brad nailer for this. I'm trying not to end up with any space between the structural post and the box around it which may trap moisture as carpenter ants are a problem on my side porch with hollow support posts. Then again, the side porch is untreated wood that sits in puddles after it rains, whereas here I plan to use those metal post bases that hold the post a half inch above the porch surface. I'll try to post a link to a picture once I get started. Thanks again. I really appreciate the replies.