Sill Plate Repair

[sopulon]

Things are not going well in my current home repair. I recently moved into a house with a radon problem. I've figured out that the radon is coming from a dirt crawlspace attached to the basement of the house. So, in order to install a membrane on the floor of the crawlspace, I've cut out much of the floor and subfloor above (the crawlspace was otherwise inacessible). Then, I discoved mold and rot. The mold I'm dealing with, but I'm not sure about the rot.

I can handle a few rotten joists, but I'm not sure about the sill plate or rim joist. The rotten sill plate runs parallel to the floor joists. How can I jack up that wall of the house to slide the sill plate out?

Al

[Wgoodrich]

If you have that much moisture under that house you need to replace all the rot then dig a perimeter drain around the outside of that home about 5' out to at least 6" below the crawl floor elevation and drain it away from the home. If you don't you are exposing to mold and rot still while you live in that home.

To replace a rotted sill plate you can lift the home about 3" to replace the sill and band board but be sure to use treated lumber to retard your rot problem.

If it were me I would raise that entire home about 2' and raise the crawl floor above the seasonal high water level. The 2' would depend on the seasonal high water table.

Raising the house is not that hard to do but depends on the size of the home and how it is built all crawl or mixing floor slabs and masonry fire places etc.

HOpe this helps some

Wg

[sopulon]

I did it, but it wasn't easy. I ended up replacing 20 floor joists and about 50' of sill plate and rim joists with treated lumber. It took up my entire 3 week vacation. My house cannot be easily lifted because it is part basement, part crawlspace and oddly shaped (original '50s home with three additions). The rot took about 40 years on untreated lumber, so I hope I'm okay for longer now. I'm also trying to grade the dirt around the house to keep moisture away.

Al

[Piper]

Is that crawlspace vented?

[bwj90016]

What did you use and how did you lift the house?

[sopulon]

Well,

My sill plate repair seems to be a popular subject. Most of my structural repairs are complete, but this is a long story so get some snacks and drinks.

Step 1: Remove ~400 sq. ft. of floor.

This was done about 2 square feet at a time. The floor was about 1.5" thick composed of layers of plank, tongue and groove, plywood, underlayment, and linoleum. For those hoping to attempt this, you'll find that each nail-cutting circular saw blade will get you through about 100 sq. ft. of floor. Upon floor removal, I learned all three walls in this section of the house were resting upon rotten sill plates and rotten rim joists. In fact, one corner of the house had sagged about 1", though this was barely noticeable from the inside. Additionally, 18 out of 20 floor joists that rested upon the rotten sill plate were themselves rotting. To give you some idea of how painful this was for me, the 400 sq. ft. of floor I removed included my kitchen and my only shower.

Step 2: Remove siding and sheathing.

I removed the bottom 2-3 feet of siding and sheating from the outside of the house that covered the rotten sill plates and rim joists.

Step 3: Preparing to lift one of the walls.

To replace joists, rim joists, and sill plates you must lift the house. Depending on your house, it is not necessary to lift the entire house at once. In my case, I was able to lift walls one at a time. I first lifted one of the walls parallel to the floor joists. To do this, I first pulled the finished surface off the inside wall I was going to lift (this sounds strange, but stick with me). I attached a 14' long 2x10 the wall studs high on the wall near the first floor ceiling. I initially attached the the 2x10 with the fattest deck screws I could find (#10). It turns out that deck screws are not strong enough, even if 3 are driven through the 2x10 into each stud. I did find that a combination of 2 deck screws and 2 16d nails through the 2x10 into each stud was strong enough. To the wall-mounted 2x10 I nailed another 2x10. Then on the dirt crawlspace floor, on the inside of the house mind you, I dug a couple of level spots for my jacks. Beneath the jacks, I placed a stack of 2 18" long 2x10's to act as pads. I have 2 hydraulic 6 ton jacks. On top of the jacks, I placed a couple of steel plates and on the steel plates I placed posts (2-2x4's) cut to a lenght sufficient to reach from the steel plates to the 2x10 beam installed on the wall.

Step 4: Lifting the first wall.

The jacks were pumped up. I was not interested in raising the wall very far. In fact, attempting to do so probably would have structurally damaged the house since I was attempting to lift a single wall parallel to the joist structure. I lifted the wall enough to remove the rotten rim joist and sill plate. When jacking up a house, you'll soon find out that you may need to extend the jacks 4" in order to get 1/4" of lift of your house. The other 3 3/4" goes into flexing of wood and the sinking of the jacks into the ground. In addition to the hydraulic jacks and posts, I also placed a couple of screw-type floor jacks beneath my "beam" to hold the wall up in case my jacks failed or the jack/post setup buckled (happened). These floor jacks were in place throughout the entire jacking process.

Step 5: Removing the rim joist and sill plate.

With the weight of the house removed from the sill plate and rim joist, they could be "easily" removed. Since this rim joist is parallel to the wall above it, there are many nails which must be cut. To do this job, you'll need the standard implements of destruction (hammer, crowbar, sawzall) and the ability to curse profusely. After the sill plate and rim joist were removed I also pried the small remaining piece of subfloor that was attached to the sole plate of the wall. Note to dog owners: Your dog can easily escape through the opening left when the rim joist is removed. Almost anything can crawl in as well.

Step 6: Replacing the rim joist and sill plate.

I first laid sill foam on the cinder block foundation wall. Then, put down a pressure treated 2x8 as the new sill plate. Finally, a new pressure treated 2x10 rim joist. A new, PT 2x10 is significanly larger than an old rotten 2x10. It was necessary to lift wall more to fit it in. If you are of the "beat it into place" school of thought, just be careful not to beat the rim joist so much that you ruin it. Because I was not lifting the entire house, and because I was lifting from the inside, I could not replace the subfloor at this time. I nailed a 1x4 to the bottom of the wall's sole plate to "simulate" sub-floor.

Step 7: Lower the wall.

Easy does it.

Step 8: Preparing to lift another wall.

With the first rim joist/sill plate replaced, I was ready to replace the second rim joist/sill plate and floor joists. I had to lift this wall from the outside of the house. I began by removing siding from above the windows on the first floor. I attached the first 2x10 to the studs (have fun trying to find studs from the outside). I then attached the second 2x10 to the first. I dug my jack locations, placed jack pads, jacks, steel plates, jack posts, and floor jacks.

Step 9: Lift the wall.

Raise the hydraulic jacks. Use floor jacks to support the beam as you lift it.

Step 10: Remove sill plate, rim joist, and floor joists.

This rim joist was quite easy to remove since it was so rotten. The sill plate as well. The gaping hole in the side of the house also provided the opportunity to remove all of the rotten floor joists. I did not try to remove them all at once but rather one at a time. The joists can only truly be replaced when the end rim joist has been removed. The other end of the joists were attached to a structural member that did not lie under a wall. If they did, I would have to lift the house at both ends of the joists, effectively lifting the entire house.

If you're good with geometry, you'll soon realize you can't replace a 14' joist with a new 14' joist from above or below if your joist spacing is 16". As the joists were being removed, I learned that whomever installed the PVC drain plumbing failed to use primer before gluing the joints. As the joists were removed, the pipes started popping apart. The bottom line: I had to replace the drain plumbing.

Step 11: Replace joists, rim joist and sill plate.

I replaced all the floor joists with pressure treated lumber. I figure the original lumber lasted 40 years, so the pressure treated should last longer, even if I do nothing to correct the moisture problem (another project in itself). I had one joist that lied directly under a wall. I didn't have the energy to cut the joist free, so I just trimmed the rotten wood off the end with the sawzall and sistered two new joists on either side of it. Again, I used sill foam beneath the 2x8 sill plate. At this point, I was pleasantly surprised to learn that I did not have to separately jack up the third wall. By lifting the end of the joists, the stress from third rotten rim joist/sill plate was relieved. I was able to remove and replace them. This may not be the case for you. In all, 20 joists were replaced. I also attached 1x4's to the bottom of the wall sole plates (after sub-floor scraps were removed).

Step 12: Lower the wall.

Whew.

Step 13: Vacation's over, go back to work.

Yes, I, working alone, was able to accomplish this in my three week vacation. This means working on the house 10 hours/day 7 days/week.

I finished the structural repairs on 8/27. Since then, I've replaced sheathing and siding (hardiplank), replaced the drain and supply plumbing (enough for a full bath and kitchen, PVC and PEX), had a plastic liner installed in the crawlspace (CleanSpace contractor), had some ductwork installed (contractor), insulated the floor (wasn't before), re-insulated walls, and installed sub-floor (3/4" T&G plytanium). In the bathroom, I've installed the tub, re-wired, tiled the tub surround (contractor), installed drywall, taped drywall, primed drywall, and prepped floor for tile installation. This has been in my "free" time.

I've learned alot, but at times I wish I was rich enough to hire someone to do it for me. Especially when my wife had to shower from a hose in the basement for about 10 weeks. I hope this post serves as both valuable advice for some and a stern warning to others.

Al

[Clutchcargo]

Good read, a major accomplishment.
How's your back?
I hope you took pictures.

[sopulon]

My back is okay, for now. The subfloor installation, on the other hand, really did me in. I have a few pictures I could post if anyone's interested. They might not be too informative and I'm sure there's some trick to posting pictures.

[Under_Miner]

My back is okay, for now. The subfloor installation, on the other hand, really did me in. I have a few pictures I could post if anyone's interested. They might not be too informative and I'm sure there's some trick to posting pictures.

Great read!!!

Looking forward to seeing pictures.

[sopulon]

I have a total of 23 pics. Rather than to put them all directly in the forum, I've used a photo web service. The link to the photos is:

http://www2.snapfish.com/thumbnailshare/AlbumID=143961601

If you don't have an account there (which you probably don't), I've created a generic account to help. Login as schwabad@yahoo.com with a password of arctic. If this doesn't work, let me know.

Al

[sopulon]

As you might be able to tell from the pictures, the joist replacement wasn't quite as simply as I might have described. The joists are in an addition to the house, and the dining room (with the large windows) is an addition to an addition addition. My house actually has 3 or 4 additions. I started replacing the joists under the dining room before moving to the kitchen and bathroom area.

Al

[sopulon]

I finally "finished" the sill plate repair (minus window trim). Attached are a couple of photos.

[pushkins]

Great job, bet your glad that's out of the way !!!!:congrats:

[Wgoodrich]

Great hearing from you on a final report from so long ago. I am proud of you for taking the challenge, asking the right questions, and the success you have shown in the pics. Great to know we helped someone succeed and to hear and see the final project. Great job !!

Wg