I have a painting contractor coming in a couple of weeks to paint my 200 year old house in eastern Massachusetts. I went out today to do some prep work. On the northeast corner of the house the corner boards and the skirt board are rotten due to poor installation and maintenance of gutters and downspouts. (The ground slopes off a bit away from the house so while the punky wood dries out I’ll be spending the day digging a drainage trench down the little slope and dropping a pvc pipe into it to hook up to a new downspout.)
I expected to find some rot underneath those trim boards to and figured if it was not too bad I’d consolidate it with some liquid epoxy, fill any gaps with epoxy putty and replace the trim boards. If it was too bad, I’d call for help. (I’m a homeowner, DIYer and I have my limits.)
Problem is, I can’t decide how bad is too bad. I am hoping for some advice here.
The rot in the sill (looks like about 8×8 timber, although I haven’t removed clapboards to see the whole thing) starts at the very corner of the house. At the corner it’s totally rotted out – I can easily stick a screwdriver into it up to the handle. Seems like epoxy just ain’t gonna cut it for that part.
Extending along the length of the sill, about 8″ away from the corner it’s solid enough that my screwdriver only penetrates less than 1/2″. About 14″ from the corner it’s solid and I can’t dent it with the screwdriver.
Can I replace just that foot or so of sill at the corner or shoudl I call in the cavalry for some serious sill work?
If I can just replace the piece, how the heck can I cut the old sill off square?
Replies
If the measurment is [8x8?] it sounds like you have a bearing at that corner. I would not mess with it; you need someone familiar with old houses to take a look, sorry.
Bobl, the 8 x 8 beech sills on my 1830s house were rotted at every corner. I was able to cut out the rotted areas and replace with pressure-treated 2 x 8s.
I used a circular saw to establish depth lines at 1 1/2-inches, then chiseled back to sound wood.
The beech is very dense, and it took some doing. The rotted wood came out quite easily, of course, but a sharp chisel surely helps when you get back to sound wood.
The overall structure of the house held the corners up; these old post-and-beam structures have incredible overall integrity. I didn't have to do any additional support, but your situation may be different.
Here's a couple before and after shots of one corner:
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Allen
Bobl, I looked up a few shots of the first sill corner I repaired.
I cut the most rotted part of the sill back square by quickly chiseling out enough to get a recipricating saw in place. Then I chiseled back to sound wood; this involved three or four feet of the sill from the corner:
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Then I shaped pressure-treated 2 x 8s to set vertically to fit into the chiseled-out area. After this corner, though, I decided to always cut back in 1 1/2-inch increments so I wouldn't have to mess with the new PT material as much as I did here:
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I rebuilt the sill by installing the PT boards set on edge; glued and screwed face-to-face. Here, one side of the corner is built up. I left a knotch so that the intersecting sill would lock into it (basically replicating the mortise-and-tenon of the original sill):
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Here it is completed, before replacing clapboards and sill trim:
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Allen
Hi Guy,
Your sill replacement job looks a lot like mine except bigger (I'm relieved to say).
It looks like you did a very fine job of fitting those PT 2x pieces in there. I was just going to lay them flat and make the bottom piece longer than the upper ones, cutting a longer section of the sill 1-1/2" high from the foundation upward to form a half-lap joint.
Is it important to orient the PT 2x pieces veritcally?
BTW, It turns out that the sill under my corner is 6x6 and it's pretty certainly not original. The corner post is a little punky too but only 1/2" deep. I'll soak that with epoxy. I would like to try to find some borate before I close it up but I don't have confidence in finding it locally.
Your pictures are a great help. I can't quite tell tho if you had a situation where you had to remove everything under the corner post during the replacement job. I am encouraged when you say that the timberframe has great structural integrity and can hold itself up but I'm nervous about knocking the last piece of sill out from under that post. Logic tells me that the house is not going to fall down - after all, the post is resting on what is essentially a damp sponge right now.
Bob
Bob,
See my post above to Rez, regarding the orientation of the 2-by material. Your plan sounds fine to me.
Yes, in a couple corners I had to replace the entire depth of the sill, leaving no support at the corner.
But my house is a bit unique. There are no corner posts. Atop the hewn sills are 1-inch by 4-inch planks stacked one atop the other to form the walls. The corners are interlaced like lincoln logs.
In your situation, if you need to remove the entire depth of the sill, to be absolutely safe you can lag a vertical support into the corner post, and set that on some sort of substantial footing. Maybe even have a bottle jack in place. But, truly, the walls of your house are the sum total of a lot of interconnected parts; as you say, there's only a sponge under the corner post now, and everything is square and in place now, right?
BTW, here's a shot that shows a corner portion of the "stacked plank" construction of my house. Because of a badly-flashed porch roof, an entire section of wall and sill had rotted. I removed the wall, but left the interlaced planks as a vertical "post" at the corner. What you're seeing are the ends of the planks from the intact wall, and the remaining first few inches of the planks from the removed wall:
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Allen
HI Allen,
That IS a weird construction, with the stacked planks. Do you think it's a regional thing? Have you seen it before or only in your house?
I did make my repair today by laying the pieces flat. You were correct that the corner post didn't budge when I knocked the soggy bits of that sill out from under. It turned out that the corner post, being original, was much larger (about 9x9) than the 6x6 sill material so it was supported by the other leg of the corner anyway.
I added a strip of lead between the stone and the wood to try to discourage the moisture from migrating upward. And because I had it lying around. I filled in behind the sill with a few inches of that blue Dow Corning foam insulation. I thought I had some spray foam insulation to seal the cracks but I did not and the lumber yard was closed by the time I realized. I attached the sheathing with screws so I can pull it off tomorrow and seal things up a little better.
Now I have to figure out what material to use to replace the corner boards. They were spliced about 8ft off the ground. The old wood is weathered and shows a strong grain pattern. All the new materials have smoothly planed surfaces and I'm afraid whatever I use for corner boards will look very different from the original materials. Not sure what to do about that.
All in all I think the repair turned out pretty well. Thank you very much for lending me the benefits of your experience!
Bob
PS: I really like the nice repro job you did on the plinth under your corner boards.
Bob, you made quick work of that project! No pictures? :(
As far as matching the corner board, I suppose you could sand or plane the old wood smooth. Or sandblast new wood to "weather" it to match.
The stacked plank technique was somewhat popular in the 1830s and 40s. It sometimes shows up as late as the 1860s, from what I've read, with examples from New England to Michigan. My house is 1830s.
It has some advantages: presumably less skill to build than all post-and-beam, fewer heavy timbers to deal with, it creates solid walls, and because the plaster is applied directly to the plank edges there's no lath necessary.
Disadvantages: Uses A LOT of wood and A LOT of nails, the walls have a tendency to bow out like an unstable stack of cards, and they tend to compress somewhat over time.
Allen
Hey Guy,
Thanks for sharing all this info and the pics! 5~6 x 1000 words
Well, truth be told I didn't make such quick work of the job. I repaired the sill and replaced a bit of sheathing but I still have to replace the trim boards and the clapboards. And now I'm off to do just that.
Thanks again for the help and any time you have a chance to post more pictures of your house, I'd love to see them. You clearly do great work. (I haven't posted pics because I'm sure mine won't measure up! Maybe... if the siding and trim turn out well.)
Bob, I still think that was quick work.
And I hope you do post photos; I'm always anxious to see details of 200-year-old houses, as are many others, I'm sure. There's always something to learn.
I've posted quite a few pictures of my house in the past. Here's a few threads showing some of the projects:
66931.1
67082.1
67119.1
88703.1
88730.1
53734.48
Allen
WNY- A while back I relaced a rotted corner sill area using PT 2x's and your process also gets me wondering how important standing the 2x's upright as opposed to laying flat and installing in brick fashion tieing in to each other and the original beam around the corner would be?
Sawing flat sections of 1 1/2" complete thru to the interior instead of chisling away the various areas within the sill and laying the PT 2x's flat in brick fashion seems so much easier than the more involved process you used.
Was this done for a strength fashion under compression, strength in fastening the 2x's together, or just a lending to a labor of love towqard a more completist solid when done?
Thanks
I hewed the main timbers six inches square, most of the studs on two sides only, and the rafters and floor timbers on one side, leaving the rest of the bark on, so that they were just as straight and much stronger than sawed ones. Each stick was carefully mortised or tenoned by its stump, for I had borrowed other tools by this time.
-Thoreau's Walden
Edited 5/26/2007 5:10 pm ET by rez
There were three reasons I installed the 2-by material on edge. None are particularly critical, so stacking the material I'm sure would work as well.
But here were my reasons:
Mainly, since the rot was deepest at the corner, and successively shallower away from the corner, it seemed to make sense to reconstruct from the deepest area outward. In most of the rebuilt corners, I took care to chisel back in 1 1/2 inch steps, so the new material would easily fit. With a circular saw, I could kerf to the depth, then chisel.
Secondly, I did consider the compression factor. Also, I figured moisture can settle on the top surfaces of each piece of stacked wood, perhaps hastening decay. (Even so, I used a notched trowel to conmpletely cover all glued surfaces with PL Premium adhesive).
Third, my sills are actually 7 1/4 inches high, which corresponds exactly to the size of a modern 2 x 8. When using PT lumber, it's most rot resistant when the orginal treated edge is maintained, as that has the greatest amount of preservative.
Allen