What is the difference (besides cost) in building a home on slab vs crawl or basement?
I just moved to an area that about 60% of newer homes are on slab. Are their problems with having the framing so close to the grade. What about water under the slab? These homes do not have drain tile system or sump pumps.
I am just trying to wrap my head around this idea.
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Replies
Where'd you move to?
SamT
Mostly, the difference is in the speed a person can turn out tract plans on a slab.
Once the perimeter of the slab is defined, filling it with concrete only takes a day. A day or two later, you can see people out working on that slab.
The other thing, at least how I see it, is that it's a tiny bit easier to "field engineer" differences in the site's actual elevation into a slab foundation than any other. And, that, is why so many tract builders reflexively build that way. That, and not having to be "smart" on perimeter drains, or budgeting for the drains, filter fabric, pumps and the like saves a smidgen of money up front.
Foundation just reads "excavate 12" (or 18" someplaces) "into undisturbed soil" for the turn-down edge. Then specify to be at least 8" above highest point of finished grade. Done.
Ok, around Austin, that means seeing slabs framed with a 2x8 at the high end and 4x8's of plywood at the other, but the formwork goes in lickedy-split. No fussing with foundation sills, perimeter walls, or the like.
I think it gives a less-good house, but, I'm biased towards wooden floor framing, too. It's also, in my opinion, less-good for sensibly insulating a house, too.
Does s-o-g have a use? Yes, warehouses, factories, industrial applications galore.
well... there are lot's of considerations
for handicapped access.. you can get the first floor in a slab house about 8" - 12" closer to finish grade...depending on the floor system
money
drainage
type of heating ( a radiant slab might be part of the plans )
tract builders might be mostly concerned with money
but custom builders will generally be concerned with the site restrictions, the budget, and the needs of the homeowner
slab, crawl, full foundation... they all have their pros & consMike Smith Rhode Island : Design / Build / Repair / Restore
everything here is slab on grade, I dont think there is a basement in the county. I would not have it any other way. i love slab on grade
Same here. Only two basements in the whole county that I know of- one I built and the other I worked on.
Oh yeah, One in the next county that I finished last year. Most people around here dont want them.
A lot of pier and beam and old style box and plank houses though. I will not work on a box and plank house anymore. Once was enough.
Hello. I would like to know what a "box and plank" house is. I know pier and beam, slab and full basement. Thanks, Rob Z
http://findarticles.com/p/articles/mi_m2843/is_n3_v18/ai_15383327
or board and batten...Life is not a journey to the grave with the intention of arriving safely in a pretty and well preserved body, but rather to skid in broadside, thoroughly used up, totally worn out, and loudly proclaiming<!----><!----><!---->
WOW!!! What a Ride!Forget the primal scream, just ROAR!!!
IMRC
lol I am glad that I haven't run into one of those! Unfortunately, I couldn't find the pictures that the article references. It sounds interesting! Thanks.. Rob Z
Texas is another world...
could mean just about ANYTHING..Life is not a journey to the grave with the intention of arriving safely in a pretty and well preserved body, but rather to skid in broadside, thoroughly used up, totally worn out, and loudly proclaiming<!----><!----><!---->
WOW!!! What a Ride!Forget the primal scream, just ROAR!!!
If this type of building is elsewhere it could very well be called something else. This is what my father called it.
I DO know you dont want to change the doors in one.
same kind of construction here or very similar...
it's referred to as plank construction...
the ritzier places have a squared off logs (at least 2 sides) in the corners and a ridge beam of sorts...
roof is done the same as the walls...
higher altitude places have a layer of felt or paper or what ever was handy between the layers...
some even have 2 horizontal and 1 verticale.....
as time went on more opposing layers have been added... these walls can get very thick doing this...
Life is not a journey to the grave with the intention of arriving safely in a pretty and well preserved body, but rather to skid in broadside, thoroughly used up, totally worn out, and loudly proclaiming<!----><!----><!---->
WOW!!! What a Ride!Forget the primal scream, just ROAR!!!
more opposing layers
Now that would be a strong house. These sawmills didnt want to spend too much of there lumber on these houses around here.
put or repair a door or window in one of those...Life is not a journey to the grave with the intention of arriving safely in a pretty and well preserved body, but rather to skid in broadside, thoroughly used up, totally worn out, and loudly proclaiming<!----><!----><!---->
WOW!!! What a Ride!Forget the primal scream, just ROAR!!!
Once was enough for me.
Your probably not going to believe this but here goes. I need to go into a little history to explain why we have them.
I live in sawmill county. I mean every few miles there is a sawmill of some sort. Back in the first half of the 20th century sawmill labor was cheap. Most mills provided houses for their workers. It was really nothing more than indentured servitude.
Sawyers made good money. they had their own mules, tools, etc. They were the businessmen.
mostly
To construct a box and plank house you need no studs, just beams, floor joists, and rafters. They take the outside course of siding (1x6 usually) and lay it horizontally. At the same time they take the inside course (also 1x6) and lay it vertically. They nail each layer to the other to make an 2" thick wall. When you install a door or window then you nail a stud (OK I guess there is a few studs) to each side of the door nail it to the siding and install door/window. Just one stud per side no header.
The doors and windows stick inside the house as they are flush with outside.
These houses are the shoddiest construction I have ever seen but they have a great shear strength. House movers love to move them because they are a breeze. But I dont think any will be around long enough to make the historical register.
The box part comes from the size- usually about 30'x30'. You usually had to work at the sawmill for X number of years to get the deed to it.
A lot of interesting pro-slab considerations in this thread.
Here's one negative that hasn't been mentioned yet, earthquakes. Slab houses don't have an ability to flex in a quake so they can't take much shaking without serious damage.
My family's home in the San Fernando Valley, just a few miles from the center of the North Ridge quake, sustained no damage during that event, even though the house is a simple stucco ranch, built in the early 50's. Neither did it receive any damage during earlier nearby quakes of similar intensity. Nor did any other homes in that development.
There are two reasons for that, according to studies made before and since those events. One is that the house is built on a reinforced poured concrete foundation, a raised wooden floor system over a crawl space. The other is that the soil in that particular area, on the perimeter of an ancient lakebed, in mostly clay.
Edit: Another interesting feature is that the floor of that house rests on a lot of piers and small carrier beams. The entire system of carriers and joists is all 2X4s. That apparently helps absorb the motion during quakes.
The homes which were damaged the most in the NR quake were built on slabs, resting on the old lakebed, which is mostly deep sand.
Edited 7/29/2007 11:42 am ET by Hudson Valley Carpenter
the house is a simple stucco ranch, built in the early 50'sA wood frame and traditional stucco structure has long had the reputation of being the most eathquake resistant box.SamT
Thats not good to know. I live on a sand hill and have a slab on grade.
My main concern is toronado's though. I have 4x6 studs and one piece 30' rafters with no knots. It was salvaged from an old railroad depot in Navasota Texas from the mid 70's. The rafters were actually 36' until we cut them.
I cant believe the city wanted to tear it down, but we jumped on it. It was over 100 years old then.
Hey, I never heard the San Fernando Valley called "the Hudson Valley" :)
We're over in Burbank, and when the lights went out in other parts of the valley for 4 days after the Northridge quake, Burbank's never went out. Guess it has to do with being on rock.
I vote for a foundation, too...after doing post earthquake repairs to slab houses here.
Yeah, been "stuck" here in Encino for most of the last year but I expect to get back home in a few more weeks.
My dad was the smart one, doing proper research about earth quake damage prevention before putting his money down on the new family residence, back in '52. Thanks to him, we always had a safe place to live.
Go home? Why, you don't like the traffic here...or the bill boards in Espanol?
I mostly manage to avoid the traffic. Timing is everything, so they say.
Having been raised here as an Anglo Angeleno within the Mexican culture, the bill boards you mentioned are all friendly reminders to me of where I am.
Edit: one can of worms...deleted.
Edited 7/30/2007 1:28 pm ET by Hudson Valley Carpenter
Oh, well THAT'S a can of worms! We'll be lucky if this thread isn't in the tavern shortly.
Oh, well THAT'S a can of worms! We'll be lucky if this thread isn't in the tavern shortly.
Apologies to all. I sometimes forget that I'm not just conversing with one other person.
I went back and deleted the big digression but not quickly enough, so it seems. Anyway, I'll not be responding to anything off topic again, in this thread anyway. :-)
I agree with you that the best feeling floor to walk on is wooden. That said, I'd build on a slab anytime and there are a number of advantages.IRC allows for frost "depth" to be achieved by buried insulation rather than simple depth. Where I live ( footer depth 36" required ), I can build a slab-on-grade home ( discussed it with our inspector ) with a grade beam around the perimeter that's only 16" deep, then insulation buried to meet the code. Some south glass with shining on the floor in winter to keep warm and an insulated perimeter that allows the coolness under the slab to come through in summer are both good things here.An insulated perimeter makes a big difference and isn't expensive on a normal home in Texas, either, but you probably won't see any tracts built that way.
"Doubt is not a pleasant condition, but certainty is absurd."
~ Voltaire
That is called aFPSF
Frost protected shallow foundation
Welcome to the Taunton University of Knowledge FHB Campus at Breaktime. where ... Excellence is its own reward!
Climate and soils type have a LOT to do with the decision and prevailing foundation method used locally
Welcome to the
Taunton University of Knowledge FHB Campus at Breaktime.
where ...
Excellence is its own reward!
Re basements, in many areas there's too much ground water for them to be feasible. In other (cold) areas you have to dig down 4 feet or so for a conventional foundation anyway, so you're halfway to a regular basement. Or you can build a "split entry" where the bottom floor is half below ground level and the top floor is elevated about four feet.
My personal opinon is that when you dig a hole in the ground, It wants to fill with water. Yes you can have sumps, but what happens if you have a power outage in a big storm.
That said,, I really like the idea of S.O.G., with infloor radient heat. Sounds like a good idea to me! Money saved excavating could build a little garage to keep the crap usually kept in basements!
Just my opinon
But what if it is on a slope.Then you need bring in lots of fill and compact it and even them might need piers.And with a basment you won't need a sump pump as it can drain to daylight.Really any talk of the different types of foundation systems are MEANINGLESS UNLESS A SPECIFIC LOCATION AND TYPE IF HOUSE IS GIVEN..
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A-holes. Hey every group has to have one. And I have been elected to be the one. I should make that my tagline.
I'm doing my first slab house right now and I'm pretty much sold.
This is not a monopour slab with a turn-down edge... due to the site I did footing/stemwall first and right now we are prepping for the slab to be poured within. So, it's not cheaper and it's not faster, at least to get to the start of framing, since we have a lot of underslab plumbing and electrical, fill to grade and compact, moisture barrier and insulation, and now rebar and radiant tubing. BUT, once we get the first stick of framing lumber in there we will have quite a bit already done underneath, no one will ever have to crawl, and there will never be insulation hanging in tatters from the joists in a drafty crawl space.
Downside might be the lack of flexibility later. We allowed water and drain connections for a possible addition later, and I've got a couple of spare conduits coming in, but aside from that a major remodel would be hell--it's a house with no crawl and minimal attic. If somehow PEX turns out to be a bad product, and the heating system fails, I'll have to leave town. In CA I had a few clients with Eichler homes who had failed copper radiant in their slabs, and man were they pissed.
Anyway, as the unhappy owner of a drafty crawl space with tattered insulation, like so many others I've seen, I'm now a big fan of slab construction.
copper fails in slab due to chemical reaction of copper and concrete, if the copper is wrapped no problems.
Dave , we're doing a slab RFH ranch right now...
i'll start a thread in the Photo GalleryMike Smith Rhode Island : Design / Build / Repair / Restore
Eichler homes are slabs with vaulted ceilings, usually 2x6 decking exposed over 4x rafters. When the heating system stops you have to put in electric heat.
I've heard brownbagg's take on copper/concrete.... makes me wonder about all these ufer grounds we do.
ufer are suppose to be brass
It's #4 stranded copper. Unless I never looked close enough and it's brass... but I doubt it.
For a slab house, you never hear these questions/problems:
The plumber/electrician cut oversize holes in the floor joists!
Does the floor deflect too much for natural stone tile?
The subfloor and/or joists are rotted from a leaking toilet."Put your creed in your deed." Emerson
"When asked if you can do something, tell'em "Why certainly I can", then get busy and find a way to do it." T. Roosevelt
In our project that is currently on the drawing board, I am thinking about elevating the slab about 24”-30” from grade (snow, water). The only thing I would bury in the concrete would be drains, and possibly PEX radiant heating. Plumbing, electrical, other wiring, HVAC etc would all come from the full attic, interior walls, and chases, as appropriate. I am interested in opinions on the feasibility of this approach.Originally I wanted a basement for my shop. This was a given from day one, or so I thought. Data from a test hole related to the septic system indicates there is ledge at about 2-3’ in the build area (the septic ended up elsewhere). Also, there are wet areas around the lot. Every few years there is some backflow from a nearby stream that does not drain fast enough to keep up with massive rainfall. Consequently there is ponding adjacent to the build area for 10-12 hours, although this year the town has taken some actions to improve choke points that used to impede the flow of water. I finally concluded that a basement would be expensive to build, and dealing with water problems could be a potential headache. Reluctantly, the basement is gone.
There was a thread earlier about tunnels in slabs. Seems to me a wise thing to do to put in a tunnel/duct for most of the non-DVW plumbing. Probably cheaper than imbedding the plumbing, since it would let you use PEX instead of wrapped copper.
So convenient a thing it is to be a reasonable Creature, since it enables one to find or make a Reason for everything one has a mind to do. --Benjamin Franklin
I suppose a guy could figure out a way to incorporate PVC conduit under the slab to allow "pulling" PEX in later, but that really isn't done that I've seen. All of our potable water piping is PEX and it's laid in the underslab fill in pipe insulation. I have some 2" PVC sleeves under the slab for CSST to be pulled later, and of course the electricians have some to bring in their service feeders and get wire to the kitchen island and a few other places. But as a guy who has remodeled in a thousand crawl spaces I think it would be very hard to allow enough flexibility with tunnels or whatever to accommodate later remodels. If you are slabbing you better build what you will want and plan to live with it.
The three main advantages are cost, reduced heating/cooling requirements, and stability of floor surface.
We're just finishing trim on an extensive remodel for another GC that should have had a slab on the main floor, but instead the inadequate crawlspace was dug out, new floor joists installed and the entire thing was tiled over. Especially with ditra over the decking, and ceramic tiles it's too easy to tell what's underneith as you're walking on the various joists, beams, sills, etc. Even with span deflections of L/720 it was a huge mistake in my opinion. I'll never allow ditra in a project that doesn't have at least a double layer of ply.
As for heating/cooling, the slab can be a great help in moderating temperature swings throughout the day. With ridgid foam under the slab, bringing the slab within the building envelope, it helps a house stay warmer at night and cooler during the day for absolutely no money. Free!
Some of the green houses we worked on in Wyoming had slabs of 8" or more, and I can't imagine a reason why a sand or gravel base shouldn't also be brought within the building envelope for still more thermal mass. With good insulation, a few well placed oversized windows and large internal thermal mass, many of these houses litterally could not freeze with zero heat and the coldest weather in a decade. One that sticks out never drops below the 50's when it's -20 with 40 mph winds just outside the door.
In a hot climate I can't imagine wanting to build with another foundation unless it's a space issue and the basement is critical.
In cold climates radiant heat is so much a no-brainer that I can't imagine building a house with a crawlspace.
With vapor and water barriers to keep the whole works dry as a bone, and modern plumbing, especially pex, the disadvantages of slabs have greatly diminished.
So, even if a slab on grade was just as expensive as a crawlspace I'd have to pick the slab every time.
Beer was created so carpenters wouldn't rule the world.
> In a hot climate I can't imagine wanting to build with another foundation unless it's a space issue and the basement is critical.In a hot climate a basement is naturally cool in the summer. I've never seen a design that really attempted to take full advantage of this fact, but in semi-southern areas (eg, Louisville) where basements are common you find many families spending much of the summer in them (though not as many as before AC became common).
So convenient a thing it is to be a reasonable Creature, since it enables one to find or make a Reason for everything one has a mind to do. --Benjamin Franklin
Hi Mike, looking forward to your photos, I am planning on building a FPSF with RIF Heating as well. ICF will be the walls and possibly a SIP roof (depending on budget).
Jim
LBJ took the IRT down to 4th St USA. When he got there what did he see? The youth of America on LSD!
So convenient a thing it is to be a reasonable Creature, since it enables one to find or make a Reason for everything one has a mind to do. --Benjamin Franklin
Thanks Dan, that was real timely. Next time I will endever to use less abbreviations, would not want to confuse anyone.
It's the newest record I have.
So convenient a thing it is to be a reasonable Creature, since it enables one to find or make a Reason for everything one has a mind to do. --Benjamin Franklin
"Anyway, as the unhappy owner of a drafty crawl space with tattered insulation, like so many others I've seen, I'm now a big fan of slab construction."That is becaue the crawlspace was not properly detailed (often required by old codes). Not because it was a crawlspace..
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A-holes. Hey every group has to have one. And I have been elected to be the one. I should make that my tagline.
Less of a construction response, more of a zoning one. In denser urban areas, there are restrictions. Lot sizes are smaller, with buildable area determined by a maximum fixed percentage of your lot. Also height limitations.
In our area virtually everyone has a basement (3'-0" frost depth here). Also walk-up attics. Building slab-on-grade reduces your volume 25%-33%.
Climate and site. A properly done slab in Florida will stay 60-65°, way less expensive to heat and especially cool.
Planning plumbing and electrical is critical, most of the houses I've worked that have slabs, also had a lot patches<G> not a problem if it's not the finished floor.
Wall framing seems to a lot harder for guys around here, and changes can mean more patches.
We've got to install exterior doors in a 4000sq' house on slab Monday. I love cutting off anchor bolts. not<G> We've also got to frame in 3 pocket doors, seems they forgot to take into consideration how the studs would be fastened when they ran the loops<G> Anybody think gluing squirrely 1x pt syp with pl will will stay put? The super does...Oy!
Whoever it is I wish they'd cut it out but when they will I can only guess.
They say I shot a man named Gray and took his wife to Italy,
She inherited a million bucks and when she died it came to me.
I can't help it if I'm lucky.
Anybody think gluing squirrely 1x pt syp with pl will will stay put? Dovetail 3 3/4" x 3/16" deep grooves in the bottom, set it in 1/2" deep skip trowel cementious mortar bed.You might want to make a T-rail out of another piece of 1x and a straight 2x. Screw into the plate thru the T-rail and level off it when you set the plate in the mortar.SamT
Interesting take Sam,what kind of ceement...thinset? I dunno, with the dovetails do you think the PL Premium wouldn't work? Thanks man<G> Someone's got it in for me, they're planting stories in the press
Whoever it is I wish they'd cut it out but when they will I can only guess.
They say I shot a man named Gray and took his wife to Italy,
She inherited a million bucks and when she died it came to me.
I can't help it if I'm lucky.
How well does PL Premium bond to 'crete with lot's of little stresses over time?All 'crete is damp and this is for a door.SamT
I'm not a crete guy...but moisture is part of pl's curing. It has tenacious adhesion, swells to fill gaps, and cures to pretty hard consistency, but still slightly flexible. Supposed to last longer than the materials it bonds? The pt plates are to hold the bottoms of the pocket door studs in place, the tops will be tight under the headers. All the doors are well away from the perimeter of the slab.I'm thinking on a radiant slab, the pt plate is going to exhibit some movement, I'm worried about something cementicious cracking loose over time. Should I? How would you prep the slick troweled slab for the cement sill base? Someone's got it in for me, they're planting stories in the press
Whoever it is I wish they'd cut it out but when they will I can only guess.
They say I shot a man named Gray and took his wife to Italy,
She inherited a million bucks and when she died it came to me.
I can't help it if I'm lucky.
Given that, PL would be fine, and as you say, it has a bit more flex than cement products.SamT
Okay, and the dovetail idea's the key<G> Someone's got it in for me, they're planting stories in the press
Whoever it is I wish they'd cut it out but when they will I can only guess.
They say I shot a man named Gray and took his wife to Italy,
She inherited a million bucks and when she died it came to me.
I can't help it if I'm lucky.
I get it!the key.Yuck yuck.(|:<)SamT
Although PL on clean concrete bonds so well I'd be comfortable with it, if you want something with better grab don't overlook the various epoxies made to bond completely with concrete. Our concrete supply house has litterally dozens that will pull the surface off the slab before the epoxy gives way.
Heck, even good ol' Simpson Strong Tie epoxy for ancor bolts would bond very well.
For the strongest bond a strip of clean steel, say 16 g with a quick sand to get rid of oils on the surface, wide enough to span the wall thickness could be nailed to the bottom of the 1x on your pocket door frame and epoxied to the 'crete. Some epoxies are specifically for bonding steel to 'crete and the house would have to be demo'ed to get the steel to separate from the floor.
Short of that, even the top of the line thinset morters properly applied will rip the surface from a slab before letting go. It sounds crazy, but the bottom of your pocket door frame can be held off the floor with screws, the heads set proud 1/4" and held in place with a 1/4" (or less) layer of thinset.
Personally, we don't lose any sleep when using pl to attach plates over radiant slabs.
Beer was created so carpenters wouldn't rule the world.
I'm feeling better about the pl. I wouldn't be bothered if was a stud wall with a load...but steel pocket door studs a like cooked linguini to begin with<G> Someone's got it in for me, they're planting stories in the press
Whoever it is I wish they'd cut it out but when they will I can only guess.
They say I shot a man named Gray and took his wife to Italy,
She inherited a million bucks and when she died it came to me.
I can't help it if I'm lucky.
Box beam them with track. Beau coup stiffer.SamT
Dang man, you've made another light go off...one opening is pair of 3 1/2'ers in a 2x4 wall...I think we'll ply the whole thing<G> Someone's got it in for me, they're planting stories in the press
Whoever it is I wish they'd cut it out but when they will I can only guess.
They say I shot a man named Gray and took his wife to Italy,
She inherited a million bucks and when she died it came to me.
I can't help it if I'm lucky.
View ImageSamT
Sam,
I would probably rip the PT into two pieces to relieve some of the internal forces and then glue/nail or tapcon or screw them down."Poor is not the person who has too little, but the person who craves more."...Seneca
Radiant slab...but I guess we could call leaks water features<G> Someone's got it in for me, they're planting stories in the press
Whoever it is I wish they'd cut it out but when they will I can only guess.
They say I shot a man named Gray and took his wife to Italy,
She inherited a million bucks and when she died it came to me.
I can't help it if I'm lucky.
Snort,
The only radiant slabs I worked on had the piping placed well down into the mud. Minimum of 2 1/2" of concrete cover over them, So I wouldn't have a problem using short fasteners to hold the PT in place."Poor is not the person who has too little, but the person who craves more."...Seneca
In that case, I wouldn't hesitate to screw... but, you probably work with professionals<G> Someone's got it in for me, they're planting stories in the press
Whoever it is I wish they'd cut it out but when they will I can only guess.
They say I shot a man named Gray and took his wife to Italy,
She inherited a million bucks and when she died it came to me.
I can't help it if I'm lucky.
Didn't read the other posts yet, but I'll put in my $.02 worth...
When we were shopping for a house, first thing on my has to have list was a crawl space. Everything is so much easier...running electrical, plumbing, cable, etc. Don't know the physics of what makes a foundation superior in an earthquake, but I have a feeling it has to do the load being distributed on the foundation walls, instead of spread around a slab.
In my part of the country, north central Texas, a slab on grade is about 1/3 the cost of a pier and beam foundation with a crawl space - assuming that the lot is somewhere near level, assuming both have piers.
The lot I'm building my house on is not level and we are going with a pier and beam. If the rain ever stops, the crew will be pouring a stepped floor in our crawl space. Ours will be conditioned space with the insulation in the crawl space walls. With the stepped floor, we will have a crawl space with 6 to 10 foot ceilings. I've decided to call it our auditorium <grin>.
The biggest advantage around here (N. Texas) for slab on grade is to keep all the foundation repair companies in business. They are fixing foundations as fast as they can be poured. Lots of people have jobs because of bad slabs. I watched one house being built where they didn't even mow the grass before pouring. When my house was built they drilled 12" piers as deep as they could then filled them with concrete and rebar. Then they poured the slab. Total extra cost - $1000. It's hardly moved in 20 years.
I have a friend whose slab sunk and cracked enough to put the house over the easement line. He had to get a special variance to level the house back up cus it was over the line.
Jim
I just moved out of a house with a basement. Here are some of the good points.
1.It's nice to have a place to put junk. Seasonal stuff like camping gear, Christmas/Easter stuff, etc,etc... If you entertain large groups you need a place to put all the stuff.
2. Mechanical equipment that goes into a basement. water heater, furnace, whole house wood stove, water softener, water pressure tank, water filter. All this stuff is easily installed, replaced, up graded, and maintained in an unfinished basement. If things leak there is a floor drain nearby. Big mechanical rooms are GREAT.
3. Energy wise the basement acts as a big thermal reservoir. When it's cold, the basement is warmer than the outside air and when it's hot outside the basement is cooler.
Your house sits on a BIG pool of temperate air with all the concrete walls surrounding it. You just have to make sure that water and radon don't get in your basement. But it's not that hard to do. If either one is getting in, someone messed up. It's not rocket science.
4. a room for young kids downstairs in the basement is a good way to get them out of your hair. You can leave the place cluttered and it doesn't matter.
I live in NE where almost all homes have a basement. My son moved to Nashville and after the first tornado came close, he sold his house with a slab foundation and looked until he found one with a basement - has been happy he did so ever since.
Also familiar with copper pipes buried in slab leaking as has been mentioned. I know that it is now practice to take protective measures but what other problems are out there? I remember about 40 years ago traveling for a potential job to southern Ohio and looking at new homes that were slab on grade. I asked the builder how you repaired a leak at that time ( they were burying the copper pipe directly) - he said no problem because the concrete will surround the pipe and contain the leak. If only that were true! But the real item is that you don't have an area to run piping if you want to put in a sink and faucet etc. somewhere. It just restricts future modifications.
Just my thoughts