I'm seeing what seems like an increase in houses and apartments built on slabs around Cincinnati.  Starting at the beginning (I'm not an architect), what is the purpose of a full basement in this region and why is it suddenly not necessary?  I don't recall seeing any structure of any kind built on a slab when I was a kid other than strip malls and oil change places. 

 

When I was a kid I recall that basements were allowed to settle for several months before construction of the house commenced.  This doesn't seem to be the practice anymore, and new homes and other buildings built on slabs obviously have no wait time at all. 

 

 

 

^ I am sure cost has something to do with it. When you can pre-fab the house in a factory and assemble it on site, it can make building much more affordable.

I love slabs. Sure you lose out on basement storage and everything has to go through the attic, but basement flooding events are so common and furnace-ruining (especially with rentals) that I like not having one now.

I love slabs. Sure you lose out on basement storage and everything has to go through the attic, but basement flooding events are so common and furnace-ruining (especially with rentals) that I like not having one now.

 

So you live in a trailer park?

 

there are many houses on slabs that are not trailers.

Most homeowners in Ohio expect a basement.  The main reason to build on a slab is COST or possibly in an area with a high water table, but even then most people prefer a crawl space so that the home doesn't have hard cold floors.  The basement doesn't add that much to the cost, but homebuilders count every single penny.  They will cheap out and cut every corner possible as long as it passes inspection and they can put granite counters and a cathedral ceiling, they're good to sell.

 

I guess one other reason to build a slab is that it is better for handicapped accessibility, because there can be built closer to grade.  I have seen lots of new landominiums and patio homes that are mostly sold to older people who want small yards and no steps.

 

A foundation does not need to settle before adding the framing.  I think homebuilding just maybe moved at a slower pace 20 years ago.  But homebuilders are all about trying to backfill ASAP and start framing.  They just can't backfill until the concrete has gained strength, but they can frame the first floor before backfilling.

 

Trailers have a frame that's separate from the slab. Most trailers sit on two "pads" that are about two feet wide by 50+ long.

I think the foundation has to sit below the frost line...so the farther north you go, you might as well just build a basement. At least that's what I always reckoned...

I saw this one this past weekend...doesn't look deep enough to be a finished basement.  As I understand it, having a deeper basement built so as to enable a finished basement without low ductwork (so a floor about 9 feet below the joists) is only incrementally more expensive, so why isn't it more popular?

^In this case, the adjacent building might have something to do with it. You don't want to affect the existing building by cutting too close to it. Notice that the drain pipe is tied.

 

The depth of the sewer, if any, could also be a factor. You can't go deeper than the sewer and still drain by gravity without pumping.

In Ohio the bottom of that foundation has to be at least 32" below finished grade but that looks a bit deeper. It might just be deeper for a crawl space, so that plumbing and ducts can be laid below the floor. You can put plumbing below a poured slab, of course, but then you're locked in and can't ever relocate it without the significant cost of sawcutting the slab and excavating, and re-pouring concrete indoors. This is why new McMansions with unfinished basements always have rough-ins somewhere for a future restroom. The cost to build it in is minor but the cost to try and add it later is 10X that, or sometimes even impossible depending upon the sewer slopes you might need.

 

Though looking at that picture it looks like it might just be a garage? There are only footings on three sides, which leaves me to believe the fourth side facing us might be just a door.

 

I think the foundation has to sit below the frost line...so the farther north you go, you might as well just build a basement. At least that's what I always reckoned...

 

This is what I think is probably the primary reason for basements. You are already digging 32" down, it's not that significant of a cost to keep going. A little bit more excavation and a little bit more concrete aren't all that pricey at this scale because there's a lot of cost just getting the equipment set up and ready and that's fixed. So you can add ~1000 unfinished square feet to a house for a fraction of what it costs to build a square foot above ground. And most people seem to like basements, where else would they put all their crap?

I know that there was an attractive-looking ranch condo development near downtown Akron that my wife and I looked at in which basements were an add-on option, not standard, when the development was built, so maybe 5/30 or so of the units have them.  We wouldn't even look at anything built on slab.  In addition to the mechanicals issue, we were still worried about the foundation cracking, notwithstanding whatever precautions might be required or voluntarily taken by the builder.

 

The depth of the sewer, if any, could also be a factor. You can't go deeper than the sewer and still drain by gravity without pumping.

 

Aha.  This is on Fergus in Northside, just 2-3 blocks north of the CH&D ROW, which was built on the northernmost edge of what they somehow knew back in the 1850s to be the extent to which the Ohio River would cause the Mill Creek to back up during major floods.  It's quite possible that the sewers are not deep in this section since they were no doubt built before the Barrier Dam which went up around 1948. 

 

Many houses in my part of town do have basements. It seems like the houses on the street that were built in the Teens and '20s have basements, the ones from the '50s don't, then the ones from about 1965 and up do have them. It's not a flooding or sewer issue. It is typical of Groveport for houses on any street to have vastly different build dates from the 1800s to only a few years old.

No engineering/architectural knowledge here, but I've notice that basements disappear the father south you go.  They are non-existent in Florida.  When I lived in NC, there were almost no basements that were not walk-outs.  My dad's house in CLT has one completely in ground, but his house is old and it is more of a true 'cellar'.  They are constantly fighting dampness issues down there so it could never be converted into a living space.  Here in CLE, most every house, even the small ones, have basements.  I did rent one house 15 years ago that was built on a slab.  Best part of that was the heated baseboards.  My current house would feel much smaller without the basement.  The rec room I finished gives us another living space, and the rest of the basement gives me all the storage room I could need.

^ In the south the lack of a frost line of significant depth is a big factor. Foundation walls can be very shallow (like 12 inches). You can dig them with a small bobcat or other cheap piece of equipment, so the cost difference between that and a full basement excavation is more significant than in the north where you need to dig ~3 feet no matter what and likely need heavy equipment.

My grandfather told me that he remembered people digging foundations with mules.  He said they dug in one side and out the other instead of just digging a single ramp. 

The 30" footing depth here (not 32") isn't really all that far down, and I don't recall running into instances where it was required to go deeper to reach good bearing soil.  Having the flexibility to run wiring, pipes, and air ducts makes at least a crawl space advantageous, if you have the space.  In the south, I think it's moisture and higher water tables that tend to preclude basements, but crawl spaces still seem to be preferred to raise the house a bit above the reach of termites and to vent the moisture out before it has a chance to force its way up through the floor.  Historically, having a basement was advantageous for coal delivery.  Cincinnati was also more of a furnace city than a boiler city, and the big old octopus gravity furnaces needed to be in the basement to allow the heat to rise up to the living floors.  I don't want to get into the details of why some areas preferred furnaces, others boiler, and others stoves, on top of the historical switch from fireplaces to central heat, but that could be a fun discussion. 

 

Anyway, another factor as touched on before is accessibility.  Many houses have a first floor that's a few feet above the yard, and another few feet above the street.  So to get a full basement would only require digging the minimum 30" required footing, piling up the excavation around the yard, and then having some more steps up to the front of the house.  I suspect that when the streets were built they were dug down to good subsoil, with that excavation also spread around the building lots.  That's how you end up with situations like this:  https://goo.gl/maps/pq4ZShri41p where the basement is almost free.  I would hypothesize that the original grade was about a foot above the sidewalk in a case like that.  It's not great for accessibility though.  Yeah the driveway ramps are generally ok, but getting that extra couple feet up to the first floor is tough for the enfeebled.  Nowadays on smaller lots like these you wouldn't be able to dispose of the basement excavation on-site, and hauling it off is expensive.

Those ramped driveways also suck in the winter since everybody parks on the street when they can't get their car up the ramp even after shoveling. Add in all the snow from the snowplows and you have a real mess. My places in Oakley and Bexley were bot like that.

On 3/21/2017 at 3:28 PM, GCrites80s said:

I love slabs. Sure you lose out on basement storage and everything has to go through the attic, but basement flooding events are so common and furnace-ruining (especially with rentals) that I like not having one now.

I am looking to buy a house in Westerville, Ohio (Near Columbus). Since I just retired at 61, I am looking for a single story home without a basement (Built in 1970 or later. I have seen a fair number of homes of this type in the area I'm looking. I am curious if most of these single story basementless homes are likely to have a slab foundation in Ohio? I got one response on another forum which said not likely  due to the frost. If homes are built on a slab, where is the HVAC ducts and plumbing likely to be run? Do people who own such homes worry about ducting or piping breaking which would require an expensive repair? Or don't problems usually occur that often ? Thanks. 

 

Tim

At my house the pipes are ran in the attic. The only reason there is any real significant piping up there is because a laundry room/breezeway was added later. The water heater and washer/dryer were moved out there from the kitchen. So initially the pipes only ran into the plumbing access from the meter where they immediately tied into the adjacent bathroom and kitchen. So the new piping is a concern up there, but it seldom gets cold enough in there to worry about freezing. There is an incandescent floodlight that you turn on in the plumbing access to keep it from freezing when it's below 15 out. This is in addition to having its own heating duct. Below 10 out I use an electric heater in the breezeway since it is an unheated space. I'm not sure it's necessary.

 

Ducting-wise any replacement would be super cheap. It's all flexible. What happens when the ducting is in the attic is that the heat becomes less efficient than it would be in the floor but the A/C becomes more efficient.

 

You really have to take it on a case by case basis to determine whether a house is on a basement, slab or crawl space if it was built after WWII. Look for basement windows for a basement, little grates in the foundation indicating crawl space or miniature plumbing access doors indicating slabs. Obviously online listings should indicate which type as well.

there is a lot of discussion around these topics here -- maybe jump in and ask? i hope it helps:

 

https://ohiobasementauthority.com/service-area/basement-waterproofing-westerville-ohio/