pros and cons of slab vs. crawl space

Discussion in 'Homesteading Questions' started by DQ, May 21, 2008.

  1. DQ

    DQ Well-Known Member

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    most of the new homes being built around here are on a slab. older homes are all built with a crawl space. I am putting together plans for a small building as much for use, as for "practice" building a substantial structure. I keep coming back to the idea that I would prefer to have a building with a crawl space. it seems much less daunting as far as actual construction because I can do a bit at a time, it seems it would be easier to plumb and run electric both as far as planning and construction as well as offering the option to alter utility lines later if need be withoutout jackhammering concrete out (aka... if I screw up the first time). I also would not have to pay for the concrete and pro finishers and feel I could confidently plan and construct it myself. (keep in mind this is all in practice for a future larger scale project (home) not just easiest ways to build a small building.)

    what are the real advantages of a slab foundation that makes them used more often (currently)?
     
  2. michiganfarmer

    michiganfarmer Max Supporter

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    I wouldnt want either one.

    I want a basement. I want the extra space, and someplace underground incase we ever get a tornado. Also Ive heard an unfinished basement is the least expensive space in a house.

    If I lived in tornado alley, I wouldnt have a house above ground
     

  3. cfabe

    cfabe Well-Known Member

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    In more southern areas like where the poster is from (oklahoma) Basements aren't as popular because you don't have the deep frostline. Up north if you're going to have to dig down 3-4 feet anyway it's a lot less of a jump to put in a basement.

    Between a crawl and a slab, you're right a crawl will make it easier to work on in the future. A friend who had a slab in part of their split-level house had to replace a drain line under the slab which required a lot of dusty cement breaking in the house, and of course replacing the floor coverings after it was fixed.

    The floor also feels nicer with a crawl space, it's not as cold as a slab and isn't as hard to walk on. Wood floors have some give which cushion your feet, this is particularly noticable if you've ever walked on a slab without shoes. One downside to a crawlspace is that it must be maintained, if you are in a wet area you'll need to check periodically to ensure there's no water/moisture in it and take care of it if necessary (sump pumps, drain tile etc). Also make sure no pests are making their home there. Slab houses don't have those problems.

    Crawl space houses also usually sit up a little higher off the ground which I think makes them look nicer than a slab house right on the ground. But that may be just because I'm used to it. Not many slab houses around here.
     
  4. NEOhioSmiths

    NEOhioSmiths Well-Known Member

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    I agree with michiganfarmer - go with a basement. You'll be much happier in the long run and won't notice any cost difference a few years after the house is completed. I'll go even further and say if you're going to do a basement, consider (1) poured walls, (2) an extra course of two of block if you going that route, and (3) make it a full basement. Basement is such useful space - root cellar, workshop space, workout space, storage, safety, .... Once you have one, you'll never want to be without one.
     
  5. mandidawn

    mandidawn Well-Known Member

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    I'm on a crawl-space, and I like it. Wish I had a basement, but whatever, next house.

    Make sure that your crawl-space is high enough to be comfortable to crawl in. So many are not, and a larger person either has a very hard time getting in there, or just cannot at all.

    Insulate really good under there. So much air is sucked down that the floors are really cold in winter (that's what I plan to do this long weekend, hang out with the spiders under my house insulating).

    Lastly, make sure you close up any holes coming into the house (for pipes and such) really good - mice hang out in the crawl space, don't let them hang out in your house.

    Good luck
     
  6. stranger

    stranger Well-Known Member

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    go with the basement, sink it right down about 10 ft. sleep in it in the summer, it's built in airconditioning, plus all of the above
     
  7. mnn2501

    mnn2501 Dallas

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    They're cheap thats the only advantage. in OK as well as any other warm place Pier and beam in the only way to go. More expensive but you won't have to have your foundation fixed or worry about the foundation moving and your pipes breaking. A slab will shift with time in the south - period,
    Crawl spaces attract critters and can cause freezing pipes if not insulated properly -- they also make for warm floors in the summer and cold floors in the winter.

    Basements are not really an option in the south, they're way too expensive due to the heat and the drying and shifting ground. They need to be re-enforced and the surrounding ground needs to be specially prepared, a basement in the south will cost 3 times what a same size basement in the north will cost.

    I love basements having grown up in MN, but living in TX theres no way I'd put out the money for one.
     
  8. OntarioMan

    OntarioMan Rockin In The Free World

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    I'm sure slabs have many advantages :

    - fairly easy install of hot water radiant heat
    - concrete is fairly inexpensive
    - concrete is quick to install
    - not having a basement or crawl space means the building is higher, less chance of flooding
    - concrete is fireproof and strong
    - concrete may be more insect resistant
    - concrete represents lots of "thermal mass"

    I have a basement, but I certainly would not rule out having a house in the future which was on a slab - I suppose it would all depend on the site specifics and economics. I know of a house on a flood plain which has a basement, obviously not a wise idea. Why was the house built with a basement? Probably because whoever built it ignored the site specifics, and had always built houses with basements.

    .
     
  9. tiogacounty

    tiogacounty Well-Known Member

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    I build in an unusually wet area of the mountains here in NE PA. My choice is a conditioned crawl space. This is a 4' tall, 8" thick poured concrete wall on a 8"x20" footer. First the floor area is filled with 3/4 clean stone to the top of the footer level, then a "rat slab" which is a 3" thick, roughly troweled slab is installed over 6 mil poly. There are NO vents and NO insulation in the floor joist. The walls are sprayed with R-10 urethane, from the rat slab to the plywood subfloor. The HVAC ductwork allows a small amount of heated and cooled air into the space. This sealed crawl is clean, well lit and dry as a ghost fart. I have had realtors, with decades of experience in the area, tell me it's the nicest crawl space they ever have seen. If your wondering why go to all this trouble and not just put a basement in? The answer is simple. I have been able to monitor the ground water level of the latest house I built, as it has a vertical dry well a few feet from the foundation wall. The static level of the ground water is the bottom of the footer +/- a few inches depending on when it rained last. So, a full basement would be located in 4' of standing water. Not an impossible problem to overcome, but why look for trouble? Google "conditioned crawl space" for more info. Good luck.
     
  10. michiganfarmer

    michiganfarmer Max Supporter

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    Jack your house up, dig the crawl out to 8 feet deep, pour new footers, lay new block walls up to your bottom plates.

    voila, a basement.

    I did it. . I dug it out by hand. I dug the footers by hand. I hauled the concrete for the footers in by hand in 5 gallon buckets. I hauled the block and morter in by hand.

    It sucked, but i have a basement
     
  11. mnn2501

    mnn2501 Dallas

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    Michigan is MUCH different that OK or TX -- it won't work here. There is a valid reason why almost no one has basements in the South
     
  12. michiganfarmer

    michiganfarmer Max Supporter

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    really? thats interesting. I dont understand how the ground shifts. How does the heat have anything to do with the cost of a basement?

    My inlaws in coastal NC say the water table is to high there.
     
  13. michiganfarmer

    michiganfarmer Max Supporter

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    they person that I was telling that to is in Michigan.

    I thought so anyway. I will go back and look to make sure.
     
  14. vicker

    vicker Well-Known Member

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    You forgot to post the reason. :D The south has less drainage problems than up north. They just went a different route in house building.
    Used to be people in the south built above ground with no under pinning for cooling purposes. Nothing sucks worse than working under a crawl space house that is only inches above ground. If you go that route, make the lowest point no lower than 2 feet (and that ain't high enough).
    Concrete slabs are the cheapest route. That is the only benefit. Standing on concrete is murder on your feet, leg, hip joints. The floor is cold. They crack and settle. Go with a dirt floor first.
     
  15. mamita

    mamita Well-Known Member Supporter

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    my brother in TX couldn't build a basement due to massive boulders, so it is on a slab. it just wasn't feasible, so I think it would depend on your land. I never noticed a difference walking around inside, maybe cause it's warmer than my house in the north. we have a crawl space, and it is better when you change plumbing and such. we've never had water issues, but do have the small vents screened with metal lath to prevent unwanted guests. we do hope to one day dig it out, cause the storage would be wonderful. guess it depends on your budget, your ambition, and your property. happy building!
     
  16. CGUARDSMAN

    CGUARDSMAN Well-Known Member

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    Not many basements here and the ones that have them they are usually walkout. We have a crawl space that is 6' just below the gravel is shelf rock which is why we don't have a basement. The Ozarks is all limestone so if a basement is gonna be built it requires lots of jack hammering and a geological survey to make sure there are no caves below the build site.
     
  17. Quint

    Quint Well-Known Member

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    I went with a basement. It didn't cost all that much more than a crawlspace in the scheme of things.

    I've never heard anyone build a house with a basement say "I like my house but I wish I hadn't put a basement under it."
     
  18. Marsh

    Marsh Well-Known Member

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    We have both. Our house is a crawl space and the apartment is on a slab. They are both sitting ontop of HUGE SLAB of ledge. When they were built there was no way to get through the rock so they built ontop of it. We could now some 60 years later have the house jacked up or moved and the rock removed because methods have changed. But honestly the expense would be cheaper to build another house somewhere else.
    Let me tell you that the house being 2 stories high and only 2 cement blocks for a foundation. Shifts all the time. The house was built in the 50's and sometimes the frost heaves make the house go one way or the other, meaning, yes, the house floats at times. Not alot but some. :) I am sure newer methods of crawl spaces stop this.
    Our apartment unit is on a slab and it has no real problems at all. All the plumbing and wiring were put in from the attic. So it comes in from above not below. Much easier to get to and much easier to find a leak if there are any. No crawling in with the creepies hoping the house don't fall on you LOL The floors are just as cold in winter with the slab as the crawl space. The only difference is you could use and outside woodstove to heat radiant floors in the slab if you want. I suppose you could also do this with a crawl space. Also you can also lay alot of different flooring on a slab than you can a crawl space. The crawl space houses tend to float alittle and not all floor coverings will float with the house. Such as hardwood floor. I was told it would crack and just not be worth it due to the float factor.
    I also think with a crawl space you might be limited on the weight the house can hold. I know ours doesn't have too many pillars under it. It is more of a foundation ouline. It does have some carrying beams to hold the weight.
    I also know that with a crawl space the air gets underneath them and if it gets damp you can risk the floors rotting out. But then again if they do you can gain easier access from above to cut out and replace.
    The toilet here once had issues and the old owner couldn't fit unneath the house so he went from above to get at the problem. Now we have a floor bolted around the toilet. So if you ever have a problem again you can access it by unbolting the floor. LOL
    Hey we might not be in the best situation with the house but I have to admit it gives the house character and we like it.
    If we ever move to another house I suppose we would have a basement. But in living in this one. There is no basement and no attic. It has taught me how to live with less. You never realize how much "stuff" you have in your attic and basement until you go to move and don't have either. LOL
    On a last note. You might check with insurance companies. I know it was hard to get insurance on the house with a crawl space because they are considered high risk. The apartment was very easy to get insurance on the slab was no big deal. We ended up getting farm insurance because the insurance company didn't like our monitor heating in either place. They said it wasn't a consistent source of heat. I refered them to the woodstove and that wasn't consistent either. I refered them to the door and found a farming insurance that didn't mind any of the above ROFL

    Sorry this is so long. Just hard to explain in few words the things we see with slab and crawl space.

    Marsh
     
  19. DQ

    DQ Well-Known Member

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    I suspected that one of the only advantages of the slab was cost. my inlaws house had to have major foundation work done on their slab. my current home is on a slab and we totally rigged the washing machine to move it out of the middle of the kitchen to avoid hammering out the drain and moving it. I kept remembering in the house I grew up in, and a trailer I lived in, the hardest part about moving or repairing the plumbing was getting down and dirty and feeling like you had spiders crawling on you the rest of the day..

    I have always had major basement envy. I have been told many times though that they are not appropriate for our area. I have thought about (eventually) building a house "in" a hill to to take advantage of the cooling effect as well as the safety (I am in major tornado alley, NE oklahoma). I could build my "practice building" in the same fashion on a small scale. my inital thought is to essentially build a retaining wall with block, with plenty of dead men, drainage and moisture barrier and than push the top of the hill down against it. there are obviously some serious details to work out but in a nutshell would that work??????
     
  20. ChristyACB

    ChristyACB Well-Known Member

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    Crawlspace here. Mine is 3 feet for a 4 foot raise at the floor due to A4 flooding zone. I love it. So much less hard than a slab and so easy to get to stuff when it goes wrong.

    That said, I have to echo what others have said. There is much more maintenance with a crawlspace and the bigger the crawlspace, the more maintenance. In my case, it is big enough to work very comfortably in, but it has drastic changes in temp and enough room to be comfortable for invaders.

    Wrap pipes, seal the accesses to the house around pipes repeatedly because they can wear, insure you get the very upgraded vents that shift in relation to the need rather than static ones and put extra insulation and a vapor barrier under the floor.

    Another consideration is the flooring. If you are getting a wood floor, be sure to pay a little more for a very thermally stable one. It will make a difference.

    As to basements, so far nowhere I've lived in VA or NC was that even possible. The water table here is just too danged high and drainage issues are significant. Can't even have in ground pools around here or where I came from in NC without massive and excessive work or else they slump inward.