I have a 50 year-old house. Half of it has a full basement and half is crawl space with the same concrete walls as the rest of the basement and a concrete slab. I don’t know if the footings under the crawl space walls are the same depth as under the rest of the basement walls.
Has anyone ever converted a crawl space like this into a basement? Obviously lots of dirt removal, probably a hole in the foundation. Possible? Stupid to try? Expensive?
Thanks for any comments or suggestions.
Paul
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Replies
Hate to be the one to burst your bubble, but the footings in the crawlspace won't be as deep as the ones for your basement, barring some very strange circumstances. Most likely they'll be around the depth required to avoid frost, which varies from 1 to 4 or 5 feet deep in the lower 48 states.
Anyway, your choices are to remove all that too-shallow foundation and jack up the house and repour, or to pour new basement walls inside of the foundation stem-walls. Not a real economical space in the end.
I guess with a concrete slab in the crawlspace you can't know exactly where the footings are, but they're probably right below the slab.
zak
"so it goes"
I have quite a bit of experience with this as I have been converting the crawlspace under my house (built in 1949) into a full basement for the last five years. I work gradually and with hand tools. So far, I've removed 4760 five-gallon buckets of hard clay. The full buckets weigh an average of 42 lbs.; so, I'm closing in on 200,000 lbs of material removed. In volume, it works out to 118 cubic yards of dug dirt, which I reckon is about 60 cubic yards of packed dirt. I carry the dirt off, 20 buckets at a time, in a 1989 Toyota pick-up truck. For me, this is sort of a hobby; I work on it when I have the time. I started on this project, dubbed the "Gacy Project" by my family, at the age of 52 and I'll be 57 this summer. I find the digging to be relaxing in the way that a gardener likes to dig in his garden. Sometimes, I find myself in my crawlspace when I really should be doing other things.
Three things that make this project doable are: the composition of the soil (clay, with no rocks); the ability to get rid of the soil (I've lined up numerous people who want it); and my masonry skills.
Is it worth it? In my neighborhood, I think it is. I live 5 blocks from Duke University and there is gentrification coming towards my house from two directions. I'm not only adding much-needed space to my house; I'm beefing up my foundation as I go. When the foundation's done, I plan on adding a second story to my house. I'll post some pictures anon.
Dude, I think you need a new hobby. All I can picture is you in your basement standing over a deep hole saying "It puts the lotion on the skin!"
"...4760 five-gallon buckets of hard clay..."
My hat's off to you, my friend. That's a lot of dirt!
Here are before and after pictures taken in the same spot.
Very cool.
The wall I built here went under the center beam of the house. I poured a footing below the existing footing and came up with masonry.
After building the perpendicular wall, I've gone along under the existing footings in 40-48-inch sections. I dig out completely under the footing, pour a new footing, then bring up masonry to the underside of the old footing. I've done six or seven of these sections so far and have just about completed my first room in the basement.
Mudslinger
I'm in awe of your work, not enough that I'd do it myself but just the same!
What's the story on your house? How old is it? Brick foundation doesnt seam that common to me, just curious.
I knew a guy that dug out his garage to add to the basement but he had 5 boys, your going solo I assume?
Doug
My house was built in 1949, the year I was born. Here in NC, brick foundations are very common. They are still being built, althought the inside wythe is usually block these days. I laid a brick foundation for a storage building last fall. Every house in my neighborhood, built from the 1920s to the 1950s, has an 8-inch thick brick foundation. My own house is a modest, wood-framed duplex. The foundation is 30-ft. by 60-ft. I am doing this solo.
Twofer here. Needed to resurface this post so a friend could see it and was curious what you were up to. Haven't seen posts from you in a while. The house didn't fall on you, did it?jt8
"In three words I can sum up everything I've learned about life: It goes on."
-- Robert Frost
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Greg
Are you supporting the old footing all teh way to the backside of it or just to teh center (under the old wall)?
DoRight, Yes, the foundation is goes all the way back to the far side of the existing footing. The footing for the lower foundation extends 4 inches beyond. You might be able to see that in some of the photos. The total width of the footing is 32-in. and the total width of the lower foundation is 24-in. I'll have a 12-inch shelf inside the brick wall when I'm done. I've completed the shelf in some areas and I'll post some pictures of it. But, for now, I need to get back to work.
Sheeze, if you're spending that much time down there, I'd get the place tested for radon. Whew! I think I would have switched to a conveyor or Bobcat or something. Sounds like 2400 trips up the steps with heavy-#### buckets to me.
I can remember watching some HGTV show where the dude was digging in his basement for 40 years or some such. Had a multitude of tunnels everywhere.
jt8
"The difference between greatness and mediocrity is often how an individual views a mistake..."-- Nelson Boswell
> So far, I've removed 4760 five-gallon buckets of hard clay.
Wow. I've removed maybe 300 - 500, never thought to keep count like that. Mine's a crawl space that ranges from 36" in front to maybe about 8" (I can't get there to measure) in back. So, I'm leaving the deep part alone, and deepening the rest to 18". I built a sort of cart that holds three buckets in a row, with axles between them and 8" wheels. The overhangs give me leverage to steer it with.
You know, there are guys who pay money to go to a gym, pick up weights, and put them back down again. We get to lift heavy buckets for free, you get a basement as part of the deal, and they think we're the crazy ones. Go figure. ;-)
-- J.S.
I can't tell you how good it is to know there are others out there. Maybe we can start a support group. We could call it "Diggers Anonymous" or something like that. We are so misunderstood.
Great job!
Like John said, sure beats paying to workout.
When I was 53 YO, needed to lose 40 # so dug out son's basement. Lost the 40 and gained 800 sq ft. Lots of rock, one 4 ft dia boulder - had to dig a hole below basement floor and roll it in wiht a couple of comealongs and chain. Did the stem wall thing 24 inches in, shelves on top the 'embankment"
Count I kept was 167 wheelbarrows at 6 cu ft apiece, as 1/2 the house already had a daylight basement.
Gained 35 of the 40 back (a few times), so likely time to build something again.
Pop did the bucket thing when I was a kid, carried a few my self then.
Junkhound, That was a clever way to dispose of that rock. I've been lucky so far but there's no guarentee that I won't run into aboulder at some time in this project. Here's a link to the story of one of my heroes:
http://www.bickelcamp.org/BurroSchmidt.htmlhound
Here's one for you, shame the pics aren't better:
http://www.hgtv.com/hgtv/gl_seasonal_weather/article/0,,HGTV_3629_1391454,00.html
jt8
"The difference between greatness and mediocrity is often how an individual views a mistake..."-- Nelson Boswell
John, I enjoyed that link to the story about Baldasare Forestiere's underground home.
My project was modest by comparison: dug out crawl space, about 2' deep, to a depth of 8', but it was only 10' x 24'. Still, it was a lot of work.
A friend gave me a 4-inch-wide conveyor belt that reached 16', which I rigged up with an electric motor used to power the wheeled irrigation sprinkler lines that are used here in the dry West. When I had bucketed enough material out, I was able to set up this contraption to barely reach up out of the hole to the bed of my old 1970 Ford 3/4 ton pickup. I had to stop 3 or 4 times during each fill to go up and spread the dirt out in the pickup bed.
The conveyor I made with high side boards and cleats to carry the dirt up and out. Took 6 months of spare time to complete the excavation. I kept track of pickup loads, not bucketfuls, and I ended up with 65. Each load was the kind that makes your headlights shine up into the trees.
There's quite a bit of lava in our area, with projections of it showing above ground just across the street. I dug in fear that I would strike lava at a point that would render the whole effort as useless..., but, not so.
When it came time to begin building up the block foundation, I could not get the building permit until I submitted an engineered design to show how I would make it earthquake-proof, since we live in a D-2 seismic zone. Not too big of a deal, it just took some extra steel and concrete-filled cores to meet the need. The engineer only charged me $200 for the design.
Today, we have a really lovely wine/root/ham-curing cellar that brings me great pleasure every time I go down there, which is at least once a day. And the old Ford survived just fine.
I dismantled the conveyor, and gave my friend back his belt and motor.
I see you're about my age (59). While the digging and carrying is a bit hard on the old joints, the work is good exercise, isn't it? I've thought about getting a conveyor but that hasn't gotten beyond the dreaming stage. I also dream of getting a small dump truck.
My project continues. I've finished the first chamber, which is 12-ft. by 16-ft. It's ready for a concrete floor. This has been delayed by two things. Money and the fact that I'm away from home for the forseeable future, caring for my 86-year-old mother. She's blind and confused and my family is trying to keep her in the house that she's lived in for the last 29 years.
I've also dug out most of a larger second room. I need to find a month or so to finish that one up. The story of my life: I never have quite enough time or money to finish anything on my own house.
How about posting some pictures of your project!
I intend to put out some pictures when I get savvy enough to do it. I have a digital camera, but the limitations have nothing to do with hardware or software--it's me. The kinds of things I understand usually have wooden handles on them or carburetors.
I hope you keep up your strength for your toughest project--caring for your mother. God bless.
I hope you keep up your strength for your toughest project--caring for your mother. God bless.
Thanks. It has been a long haul but very gratifying.
Support? I got a 12 ft. piece of w8x15 steel, and a bunch of cutoffs of 4"x8" to use for cribbing. A couple bottle jacks to transfer the load, and some shims, and I can keep things well supported while I re-make parts of the foundation.
As for groups of us, I have a friend in Silverlake who did the whole dig out a basement thing, too. I should look him up some time.
-- J.S.
Here's another attempt to provide a link to a story about one of the greats, Burro Schmidt: http://www.burroschmidttunnel.org/burroschmidt.html
People like this fascinate me. I'm not sure why, maybe because it proves what can be accomplished with long-term dedication.
If my math is right, I figure Burro Schmidt moved about 1,000 lbs of rock per day, 7 days a week for 32 years. That's pretty impressive, especially considering it was all done by hand.
Anyway, good luck with your basement. I can see where you forum name comes from.
-Don
Here are a few more before and after pictures.
Kinda cool! Looks very substantial! LOL!
How many sq ft will you have in basement when complete?
"How many sq ft will you have in basement when complete?"
The present foundation is 30 by 60. For the first 12 feet of the 60-ft. length, I'm going all the way to the outside walls and building under the existing footings, as shown in the pictures. The grade goes uphill from this section and I plan on moving the basement walls in 6-ft. or so from the exterior walls. If I stick with this plan, I'll end up with about 1200 sq. ft. of basement. I'm digging this so that the distance from the top of the finished basement floor to the underside of the first floor is a full 8 ft.
Hi Mudslinger!
I read this thread with fascination today. I have been conjuring thoughts of excavating my own crawl space in a similar fashion. However, I'm not sure I have the wherewithall to do the 5-gallon bucket transport thing like you.
Recently as I turned over the scheme in my head, the idea of a water-pressure excavation came into my pea brain and won't leave. Instead of transporting the fill in buckets, could I use a pressure washer wand and a slurry pump to carve my way through my crawlspace?
I think our soil base in my central Indiana neighborhood is similar. Not clay, but some kind of really hard compact yellow dirt. I dug a 4ft trench by hand once, and everything after the first 10 inches was misery. No rocks, which would be nice for a slurry pump, but such hard dirt that every pickaxe chunk rang through my body.
I've been asking around but haven't come across any real negative issues on this method yet. (Obviously I'm avoiding asking the right people). So that is why I'm posting in this forum today, to get the real "dirt" on how much of a boneheaded idea this is. Somebody please stop me! Or at least point me to a thread where this has been covered in detail.
Madarp,
I know the soil under my house extremely well but I can't say how yours behaves. Using water pressure to excavate my own basement would not work. For what I'm doing, the soil next to the excavation needs to have enough load-bearing capacity to hold up the walls and piers. The soil I'm dealing with is clay. When it's dry and mildly damp, it has an abundance of cohesion and load-bearing capacity. You can carve a set of steps in it that work for decades--as long as they stay dry. (I've seen this in some of the older houses I've worked on around here.) When this clay gets saturated, though, it becomes mush. I've worked hard to keep the soil as dry as possible when I get near load-bearing areas. In your case, the soil may not be subject to collapse when saturated or there may be some way that you can control the process and remove dirt a set distance from walls and piers. I can't say. If you want to give it a try, I'd say start slowly and refine your technique gradually; these kinds of jobs can be structurally disasterous and dangerous. Also, keep an eye on your water bill.
I think your advice about starting slowly is the key. My plan is to first make a test dig in the center of the area away from all the load bearing walls, and try out all the mechanics of it. I'm not really sure even what kind of pump I should use. If that goes reasonably well, and my soil does not turn to total mush, I could see a process of excavating a series of narrow trenches radiating from the center outwards, and letting them all thoroughly dry out before starting the next series. I would try to cut each trench so that the runoff slopes back to the center pit where the pump is located.
Good idea to keep an eye on the water meter also. I have no idea what the GPM flow rate is on those washers. Also, I have a friend in the Hydro Geology business whom I have yet to consult about this scheme. If I actually end up proceeding, I will be sure to make a video documentary about the whole affair.
Another approach is to use air instead of water:
http://www.air-spade.com/technology.html
-- J.S.
I knew there was a reason I posted to this forum, you guys always know the right tool for the job. That air spade is a cool tool! I had never heard of it before. From the figures given in their table, excavating my 900 cu ft would take about 20 hours, if I believed everything I read.
Unfortunately I don't think my budget would handle the $2k for the kit, and I seriously doubt if I could rent one of these from Hoosier Tools. But I want one! I really do like the idea of not getting anything wet during the operation. I wonder what kind of air pull I could get with a shop vac ..... ?
Google around, try to find one used. Even if you buy one for $2k, and sell it in almost-new condition for $1500, it probably beats renting.
-- J.S.
Fifty years from now when some new owner owns the place, they are going to look at taht basement and say "what the heck was going on here"?
"I started on this project, dubbed the "Gacy Project" by my family, at the age of 52 and I'll be 57 this summer."
Now there's an obscure inside joke... ;-)
this project, dubbed the "Gacy Project" by my family
Now there's an obscure inside joke... ;-)
Until I read your post I hadn't any idea of what he meant by the "Gacy Project."
John Wayne Gacy. Buried the bodies under his house.
Mudslinger: YOu are insane . . ah . . . in a good way . . ah , ya . . in a good way. LOL!!!
WOW! I thought you had to be sent to prision in a third world country to be sentenced to that kind of five year project. What you in for Max?
Actaully I can relate a bit as I too enjoy the accomplishment of teh crazy or nearly impossible as well.
This is a fascinating thread. My grandfather did the same thing to his 1920 something house. Although all he started with was a 4'x8' "fruit cellar". Although I don't know how much square footage he ended up with, it was an large old victorian style house and he did the entire footprint.
This was all done before my time so all I have are my dad's stories about the work that was done. To be quite honest, I was a tad bit skeptical. Now I read this and I can see that it is possible.
Grandpa was a banker....came home at 5:00, got rid of the suit and tie and started digging. He too used the five gallon bucket method. Unfortunately, he only had a sedan so could only transport 8-10 buckets at time. I didn't think there were people in the world today that would take on such a project. Thanks for sharing and good luck to all of you!!!
Glad to hear of your dedication to a basement. I wish I could stick with something that long.
Anyway, I just had to drop in and tell you about a neighbor across from my mother. He dug his crawl into a basement using primarily a 3.5 HP roto-tiller. He would then rake/shovel the dirt in either buckets or the bed of his old truck, dump the dirt after work the next day and do it all over again. I don't remember how long it took him, but I know it was more than 2 years.
Turned out nice after he finished it about 5 years after he started.
I find the digging to be relaxing in the way that a gardener likes to dig in his garden. Sometimes, I find myself in my crawlspace when I really should be doing other things.
Mean wife?
Thanks for posting your experience with us, makes for an interesting read.
I to have a crawlspace although only a small portion of my basement, but a dumb idea when building. My son & I keep looking at this area as a good project for badly needed storage but get the evil eye & resounding no from the wife.
My soil is mostly sand and gravely sand with a small 3" band of clay running thur it and I have on site disposal where we really need to fill.
Best of luck with the rest of your dig.
Paul
No one should regard themselve as "God's gift to man." But rather a mere man whos gifts are from God.
Mean wife?
Sometimes. But who wouldn't be if they had to put up with me and, for the last five months, my mother?
If you've got a place to put the dirt, you've way ahead of the game. Dirt disposal is my main problem.
My parents house had a crawl space, until previous owner had a basement dug. Oldtimer in the neighborhood said they had a small bobcat type digger under there. No jacking of house was required. The basement walls are 20 inches inboard of the original foundation. All block.
As previously stated, depends on your soil as to whether a cave-in would happen while digging.
You're probably looking at a huge amount of work. How much value will the additional basement add to your home? Or how much would you value the additional storage space?
Option 1 : hauling it out in buckets. Wheew! As another responder has mentioned, that is a lot of buckets of dirt!
Option 2 : Come from the outside. If you have a big enough yard, dig a ramp down and through the foundation. Then you can use a Bobcat or such to dig out the crawl.
Either way you do it, you have to be VERY careful that the house above is supported. It is very likely that the crawl footings don't extend down as far as the basement footings, so once you get beyond the crawl footings you have structural issues.
jt8
"The difference between greatness and mediocrity is often how an individual views a mistake..."-- Nelson Boswell
We did something similar a couple of years ago. We had a bungalow reno. and the front portion of the house, including the enclosed front porch, was crawl space. The front porch area was starting to settle and the owner wanted more basement space.
The way we approached it was to:
This is not the cheapest way to go but it is fast and efficient.
I investigated this when I moved into my house 25 years ago or so. At the time, there was only one contractor in the area who dug basements under existing houses, and he wanted the huge sum of $17,000 (our entire 1,000 square foot house is built over a crawl space). We turned it down mostly because he was in very frail health, but if I had to do it over again, I would have accepted the offer in a minute.
There are two ways (as you can guess from other posts). The "correct", but very expensive way is to carefully build a full foundation under the existing house. You need to do it in small sections, or else support the entire house with I beams while you do it. The inexpensive way is to leave the house supported by the existing foundation, and dig the basement out two feet inside the existing foundation. The problem with this is that you get less space, plus the detailing at the top of the wall is trickier.
I was told the nastiest part of the experience is that diesel fumes from the bulldozer fill your house something awful. As others have mentioned, there is some risk involved, both to the existing structure, but also that you hit some unimaginable rock, and there's no guarantee that your basement will be dry (but they'll usually use the same technology used to keep modern basements dry today).
If I were you, I'd definitely try to get some estimates, but make sure the contractor has done it before, and check the references. You may find not many are familiar with this type of work.
Hmmm... From reading your note, I can't tell if you're thinking of having this done or doing it yourself. I remember there was a guy in my neighborhood slowly digging his own basement. I suspect every community has one!
we thought about doing the whole house, settled on about 500' of finished space, most of which is under a new addition. even though we excavated normally for that, there was still a lot of hand digging due to complexity of interfacing old and new (and some unexpectedly shallow foundation walls).
I saw something at the rental place (after I was done, of course) that looked like a hopper, which would be perfect for this sort of job. think constantly rotating conveyer belt at angle with buckets -- i'd ask around at your local place. 5 gallon buckets are a lot of work...especially if you don't have stairs. good workout though ;-)
So did you ever do anything about converting your crawl to a basement?
jt8
"In three words I can sum up everything I've learned about life: It goes on."
-- Robert Frost
No. Too much work. I am currenly building an addition on to the garage for a shop and storage.