Recently bought a “project” house, with eyes wide open. Biggest issue is a partially failed foundation from a 1964 “remodel” on original 1957 home. Due to erosion (drainage now solved), bottom of footing is exposed, and footing wall (gable end) has cracked through in three places (wall is about 18′ linear in total, so cracks every 6′). Wall has crowned, with both corners dropped about 1 1/2″.
Structural engineer has designed new spread footing at corners, and smaller spread footing under each crack. Fine to support the wall, but it won’t get the house back to square, and we’ll have to shim the sill to do that. (Other ideas that have worked would be really welcomed.)
Looking for ideas on how best to get the house back square, and really deal with this failed wall, rather than just a patch. Extending the room out a few feet, pouring a new footing/wall and demo-ing the existing was a consideration, but not viable.
Plan now is to put in a temp beam in the crawl, close to the failed wall. Get that beam carrying some load, then open the exterior wall and release the sill. Then jack the house back true on the temp beam, demo the existing footing and wall, hand dig and form a new footing and wall, and pour that at appropriate grade to carry the again square structure. Then reattach the existing sill. The work space/tolerances will be really tight to form this, but I haven’t figured a better plan, and so ask you guys who have been there before.
Thanks.
Replies
If I'm reading your post right, the corners have settled. My usual approach would be to go in there with either steel or wood beams and jack the floor back up until it's straight/flat/level. Get the weight entirely off the concrete, so that it can be completely removed and replaced. Sounds like you should take out all 18 feet of it and pour new, with rebar doweled into the existing walls at the corners.
You're only talking about the one wall, but when the corners are down the adjacent walls going down the sides are usually affected. Get a laser or a water level and see how the whole building sits, decide how far you want to go.
Lots of discussion here about jacking... about whether to jack the whole thing in one shot or to move it slowly. If you have the time, I suggest the latter... a few sixteenths every day or two. Some time is needed for it to settle back into line anyway. You'll be able to tell by the horrendous sounds when you're going too fast. Screw jacks are necessary for anything you're going to leave for long, as bottle jacks tend to leak and settle... at least all mine do.
Remove the nuts and washers from the mudsill. Jack up the house level. Drypack under the mudsill gap. Reattach the nuts and washer if there is still enough thread. Youll have to do it again if the foundation is not good, but this way i've done 10 times and they are still OK.
Good solution. Thanks.
If I follow the engineer's idea of supporting the wall with five spread footings, and then drypack as you suggest, will I save much time/money over simply knocking out the old footing/wall and forming a new wall? If I skip the foundation support that would be great, but the bottom of the footing is already on grade, with little solid soil below it.
Again, thanks.
Jeff
If I cared much about the house I wouldn't try to load a footing that had washed out underneath. In my opinion it's better to get it out of there and repour new. The wall you describe with that much damage doesn't have much life left, even if the engineer will let you fix it.
My solution only works on the assumption that the footing has settled 90% already. As time goes by settlement of dirt is less and less. But if the ground is active, there will be problems.
Check and see if the center section that didn't settle is level to the opposite wall. If the center is solid, maybe the dirt in the corners are too. The drypacking is quick fast and easy. Five years down the road will help you better evaluate the situation to see if you need further work.
Houses in New Orleans are out of plumb more than yours, they seem to just live with it. Feels funny when the room is tilted.
Given this wall is the only structural problem, I'm thinking the house deserves to have it jacked out and repoured. In more than a couple spots, there really is no ground/footing contact. And where it has failed, the complete footing/wall has broken through clean, with the ends dropping. I'd go for the drypack, but the wall is truly shot.
The worst part of the job then looks to be getting the forms in place (once the house is carefully leveled and the old footing/wall removed) and doing the new pour. Little clearance in the crawl. My plan would be to release the sill, jack the wall up a bit above level, form and pour. But how much jacking above level can I get away with? Seems the only way to get new sill anchors in is to drop them through existing sill holes (and perhaps a few new) due to the existing (then jacked up) sill sitting only slightly above the form. And its tough to imagine vibrating the concrete, or actually getting it into the form in the first place. Guess an option would be to pour the wall a bit short, and then drypack the gap......
Thanks for your advice.
I'd consider laying up a block wall..esp. if getting forms in is a hassel..anchor bolts can be set like ya said, and fill the core.
Spheramid Enterprises Architectural Woodworks
Repairs, Remodeling, Restorations.
Yep that's where I'd go with it. The block, I mean. Last summer we took two feet right off the face of a brand new 2 story colonial that got staked out too close to the street. The town wouldn't budge on the setback and grant a variance (sp?) to the builder. The house wasnt' even sided yet and we were doing major remodeling! Anyway.... the basement wasn't poured yet, so they just pulled back the stone, formed and poured a new footer and then layed up the block as high as they could. We took it from there.
Jeff
We do this type of work all the time. Usually, our first step is to bring in our pressure grouting contractor to inject grout into the soil beneath the foundation with the intention of underpinning the footers. We prefer to have them drill until they hit bedrock and then grout from that point upwards in the case of sinkholes. I am going to assume that a sinkhole was not your erosion problem. (Big assumption) In this case, it may not be necessary to grout to such a deep depth. Your footers could be underpinned by grouting done from the interior. Pipes are driven with 90# air hammers around the foundation at angles under the footer until the point of refusal and then grout is injected as the pipes are removed. It is not inexpensive, but it could save your existing foundation.
carpenter in transition