I recently bought a 1940s home in Kansas City. The cedar shake siding on the back of the house currently rests on the concrete walkway/driveway along the back of the house and is beyond repair. What can I do to replace the siding and prevent future rot?
Dan O. ~ Kansas City, KS
Hi Dan. The cedar shakes running all the way down to your exterior walk is a bad situation to say the least and with there being no difference in elevation between the walkway and your interior slab, I'm surprised you haven't had water intrusion in that area. Not having a treated bottom plate doesn't help matters either. I'm amazed this got missed by your building inspector, but I guess it's difficult to catch everything.
The ideal solution would be lowering the walkway so it's below your interior slab, but that would be a lot of work and probably not feasible at this time. If your bottom plate isn't rotted, it might be best to leave it alone as well. I would just concentrate on taking care of your dry rot repair at this point in time and that sounds like it's just a matter of replacing at least one of your rows of cedar shake siding.
When cedar siding is installed, you start at the bottom and work up the wall. That means you are going to have to loosen some of the rows of cedar siding above the bottom row to do your siding repair. When you have everything loose enough to get in and remove the bottom row of shingles, I would give some thought to installing some sort of flashing before putting the new shingles in place.
Kansas City and actually all of Kansas can be prone to receiving some pretty severe thunderstorms and driving rains and with your condition there, I would do everything possible to make sure none of that rain gets into your home at that point. Putting a good bead of caulk between the slab and the bottom plate could also help.
I would apply a sealant to both sides of your new cedar shakes before installing them -- due to their location they may eventually rot again, but this should help slow down the process. This is simply a dry rot repair and isn't going to correct your ongoing problem, but as I mentioned, that could be costly. If the water isn't finding its way into your home and you're just having to replace a row of cedar shake siding every ten years or so, that might be the best way to address the situation at this time. However, if it gets worse, you may have no choice other than changing the exterior grade.