Rotting Porch Wood in Contact with Concrete

House Repair Talk

Help Support House Repair Talk:

This site may earn a commission from merchant affiliate links, including eBay, Amazon, and others.

ertolsma

Junior Member
Joined
Jan 27, 2018
Messages
2
Reaction score
1
About 6 years ago we hired contractors to build a screen porch to connect our house and (formerly) detached garage. Now I've found that they rested some of the wood directly on the brick & concrete step landing at the door. Unsurprisingly, this has led to rot.

You can see from the pictures that I've removed the horizontal board that was in most contact, it was in bad shape. The interior plywood is mostly offset just off the concrete so is mostly OK. The vertical tongue and groove siding also has a couple inches of rot on either side, so I will probably cut it all even with the height of the removed board and replace with one long piece that runs the length of the landing.

My main question is: how do I protect the new wood from having the same problem? It's going to have to rest on the concrete again. Can I just attach some copper flashing to the bottom of the board? Should I caulk the edge where the board meets the concrete?

Thanks in advance for any expertise you have. I've just found these forums and happy to be here. Hopefully I've picked the right subforum for this post.

Erik

20180127_125218.jpg

20180127_125201.jpg
 
Welcome to the forum.

Is the wood that rotted pressure treated lumber first off?

I will take a guess others will be along shortly. I would cut the siding back some amount and then slip a Z shaped flashing in behind it and then install a pressure treated base board painted to match under the Z and held away from the concrete and brick maybe a ¼ “. Then caulk the gap.

Lets see what the builder pros say.
 
About 6 years ago we hired contractors to build a screen porch to connect our house and (formerly) detached garage. Now I've found that they rested some of the wood directly on the brick & concrete step landing at the door. Unsurprisingly, this has led to rot.

You can see from the pictures that I've removed the horizontal board that was in most contact, it was in bad shape. The interior plywood is mostly offset just off the concrete so is mostly OK. The vertical tongue and groove siding also has a couple inches of rot on either side, so I will probably cut it all even with the height of the removed board and replace with one long piece that runs the length of the landing.

My main question is: how do I protect the new wood from having the same problem? It's going to have to rest on the concrete again. Can I just attach some copper flashing to the bottom of the board? Should I caulk the edge where the board meets the concrete?

Thanks in advance for any expertise you have. I've just found these forums and happy to be here. Hopefully I've picked the right subforum for this post.

Erik
Can you post a photo just like that with the door open?
 
I would not use wood, I'd use vinyl lumber instead.
And yes it can be painted to match the siding.
 
Bud, yep, it was pressure treated wood. The rot was a lot worse than I realized once I pried the board off.

Neal, here's another picture with the door open, if that shows you what you're looking for.

Joe, I've never worked with vinyl lumber or even really looked at it while wandering around the lumber aisles, but that sounds like it might be the best long-term solution to avoid any future contact rot on that concrete. Are there any special tips or tricks for working with it, or is it pretty straightforward?

20180130_130706.jpg
 
It cuts, sands, drills, paints just like wood.
They must have missed Building class 101, T-11 should never be closer than 6" to any grade.
That wall should have been waterproofed at the bottom of the wall before that stoop was done. (storm and ice shield works)
It never should have been in direct contact with the wall.
I'm not seeing a termite shield on top of the foundation.
 
Just don’t forget your check book when you shop for vinyl lumber.

It is great stuff though. I had a wheelchair shower in our house when I bought it and the curb to keep the water in was a quarter inch if that so a chair could roll over it. Great if you need it but was always letting water out. I made a new curb out of a piece of 1x6 and attached it and sealed it in. it is wet 99% of the time and 5 years later looks like the day I put it in.
 
I would look at the whole area instead of just fixing todays problem.
I would cut the floor boards off where they are sticking out that inch or so,
Cut the siding across at the same level as the top of the floor.
Slide a Z flashing up behind siding so it will protect the top of the new lumber a flash on the floor to come out over the new lumber and then fashion some sort of threshold that fits between the two doors. if you have two doors.
 

Latest posts

Back
Top