I am going to replace a rotting column on my small porch. I am going to use a 4×4 post mounted on a simpsom adjustable post base. The 4×4 will be covered with 3/4″ MDO plywood. I will cover the exposed plywood edges with some outside corner molding. I plan on treating the post with preservative and priming with an oil primer before installing the MDO. Then the MDO and corner molding will be painted with an oil primer and top coat. I plan to keep the MDO and any base about a 1/4″ off the concrete.
Does this sound like it will hold up to the elements? Is this how porch columns are generally made? Any advice would be appreciated because I am not a pro, just a DIYer. Thanks guys or gals. I should have mentioned that it will be caulked before the topcoat is applied.
Replies
Is there a reason you`re going to use a 4x4 that needs treatment. Why not start with pressure treated lumber? Wrapping with MDO is an excellent idea although I`d miter the edges as apposed to applying a moulding unless you`re attempting to match an existing column. Also remember to paint underside of base sitting up 1/4" from concrete. Just cause you cant see it doesnt mean it wont get wet.
J. D. Reynolds
Home Improvements
"DO IT RIGHT, DO IT ONCE"
Have read several places recently that you should leave vent spaces, top and bottom, for air travel. sounds like bottom ok, how about top? I have no experience, but it sounded reasonable to me. Go get it!
Dan
Jaybird, yes I thought about mitering the corners but then I thought it would be pretty tough to accomplish a nice tight miter joint the full 8' length of that post. If there is any twist or such in my post the miter joint will be affected. Cutting a miter on a 8' long piece of plywood presents a challenge also. I have a nice table saw but still. I was discouraged from this idea when I took a look at a new house being built in my area. The posts on the porch were MDO wrapped with a miter joint and there was large gaps with lots of caulk. I am worried about the exposed edge of the MDO. Thanks for the help--Jay
I rip my MDO a little wider than the widest measurement of the 4 x4 to give myself some play. I also over cut the miter so that outside edges are tight when fabricated. Glue and clamp three of the four sides together prior to installation so that you can assure nice tight miters. Slip the open box over the 4 x 4 and glue and clamp the fourth side. After glue has set attach MDO post to PT 4 x 4. Allowing the 4 x 4 to dry out for a while prior to installation will help ensure that you get no twisting though there are no guarentees. Just be sure to wrap it shortly after installation.
Best of luck! And let us know how you make out!
J. D. Reynolds
Home Improvements
"DO IT RIGHT, DO IT ONCE"
Edited 6/9/2002 10:39:12 PM ET by JAYBIRD