Slab, Crawl-Space, or Basement

[pluckem]

I am hoping to learn some things from the people on here who have built their personal home or build homes/buildings for a living.

We live in Bis-Man area and looking for a lot for a future home build. Lot size probably 1.5 - 3 acres in size. Finished Sq. Ft would probably be 3500-4000 with 3-4stall attached garage and detached shop.

SO onto my core question. I am trying to compare lots as they come up but the lots in South Bismarck would require fill dirt and no basement. Obviously that dirt will add to the cost. Also I am assuming it will cost more money to get 3500 sqft finished above grade than it would to say build a 1800 sqft ranch with a finished basement (total finished around 3500 sqft).

Your roofing a larger area, your siding a larger area, you still have to have a foundation below the frost line, etc ...

Does anyone have a general rule as to estimate how much more money? Would a slab vs crawlspace make any difference?

Im not a huge fan of a typical 2 story layout. Maybe a rec room above the garage with a kids bedroom or two on that second level would be ok if that offers some savings.

I am just trying to compare that situation with some of the lots north of town or east of town that would require no added fill and no restrictions on basements.

 

[deleted_account]

I cant comment much on price, however if you end up having a crawlspace you absolutely need to have it completely encapsulated and made a controlled environment with a commercial dehumidifier/purifier. I used to crawl in a lot of crawlspaces for my previous job and you cannot imagine the nasty shit that festers under a home that ultimately ends up in the air you breathe.

Just something to keep in mind.

 

[eyexer]

If your not going to do a full basement do just a slab and no crawlspace. The cost is higher to do it all on one floor for sure. But probably not a huge amount. 25% probably. But I would do all the extra space above the garage if possible. That would be less money. The cost per sq. foot is pretty constant no matter where you put it. If you do a basement you have floor truss/sheeting costs too vs a slab. With just a 4' foundation wall and a slab you have a lot less excavating costs and of course foundation costs.

 

[KDM]

I wouldn't buy a house without a basement. Finished, it's tax free living space, unfinished it's tax free storage space. With wet bar, big screen tv, and taxidermy, it's a married mans ultimate man cave that's cool in the summer and warm in the winter.

 

[pluckem]

If your not going to do a full basement do just a slab and no crawlspace. The cost is higher to do it all on one floor for sure. But probably not a huge amount. 25% probably. But I would do all the extra space above the garage if possible. That would be less money. The cost per sq. foot is pretty constant no matter where you put it. If you do a basement you have floor truss/sheeting costs too vs a slab. With just a 4' foundation wall and a slab you have a lot less excavating costs and of course foundation costs.

eyexer - You mentioned the cost per square ft is constant no matter where you put it - I am assuming you mean the cost to finish (drywall, floor, lights, HVAC, etc) once its enclosed.

you laid out some items that would save some expenses going the slab route, but still mention 25%. Are you saying if a ranch with finished basement costs $400k, that a slab on grade with equal finished sq ft would cost $500k?

 

[Kurtr]

I wouldn't buy a house without a basement. Finished, it's tax free living space, unfinished it's tax free storage space. With wet bar, big screen tv, and taxidermy, it's a married mans ultimate man cave that's cool in the summer and warm in the winter.

Yep living without a basement up in this country is out of the question for me. With the advancement in ICF forms it is the only way to go

 

[LBrandt]

Ditto with KDM and Kurtr. Its easy to heat and cool, insurance is maybe cheaper per sq. ft. Place to hide in a storm, slab and you got a mobile home without wheels. Crawl space are nasty as said before, nothing but a spiders paradise and cost about as much as a basement. Bonus rooms over garage good idea if fire proofed right in garage.

 

[raider]

we've had all but a slab on grade... crawl is a waste, as the price difference between 4' and 8' walls would only amount to another 4' of concrete to double your square footage... left untouched, the energy required to heat and cool it would be less than the cost of a 10x10 storage unit per month...

my next (hopefully last) house will be a ranch on a sloped lot with a walk out basement to the rear facing se with a huge main level deck over the top covered by the top roof to shade both levels... love sitting out on the deck drinking beer on a rainy day, or getting in some target practice if you're out of town with nobody behind you... a sliding door also makes moving stuff in and out of a basement pretty pain free...

a few more majors for me would be spray foam throughout, 2 additional bathrooms and at least a wet bar drain roughed in downstairs (even if you don't plan to use them right away), the stair run up against a wall (straight or U shaped), and clear span scissor trusses (trust me on this)... when you decide to finish it, the clear span will give you many more options as far as layout, and you will not have to box in heat runs and give up ceiling height... BIG deal imo...

kudos to you for doing your homework ahead of time, and good luck...

 

[Retired Educator]

Lot's of good points. If it were me and I wanted a basement I would have full 8' ceilings and floor heat. If there is an area that is not going to be finished install everything that you might need later and will be a pain in the butt to install later. Plumbing and wiring are 2 that immediately come to mind.

Basements are not usually completely tax free. I'm thinking that there is some tax figured on living space. For example a finished basement is taxed differently than an unfinished basement. Don't know that formula but I don't think it's completely tax free.

A very important issue with basements is the water table. Water in the basement is no fun and needs to be considered. Check it out as even building on higher ground doesn't insure against a higher water table. Basements partially in the ground make for a little more comfort. Having windows is more appealing and egress windows need to be considered. They might even be required at least for bedrooms for safety.

The good news is that you are already thinking and planning and looking for ideas. That will help with your finished product and you will have a home that is comfortable and satisfying. Not a great time of year for this but attending a Home Show (most often in the spring) might give you some really good ideas that won't break the bank.

 

[pluckem]

Lots of good stuff, thanks guys!

I hear you all on a basement. College house was ranch with finished basement (in Grand Forks, and needed working sump to keep dry), First house was a split level with a walk out, and current house is a ranch with a fully finished 8' basement.

If given the choice I think we would build a ranch with walkout with 9' ceilings. However that limits the lots and neighborhoods available.

A few developments south of Bismarck do not allow them (water). We are just looking for a lot now and wouldn't build for 2-4 years, however I am trying to keep the final price in mind before we buy a lot and realize that we will need $30k in dirt and pay an additional $50k+ to get the finished sq.ft. we will need with a slab foundation house. If it is an additional $80k , I want to make sure we factor that into the price we are willing to spend on the lot.

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Since the actual build is so far out we don't have any builder picked out. Otherwise, I would pose this question to them.

 

[eyexer]

eyexer - You mentioned the cost per square ft is constant no matter where you put it - I am assuming you mean the cost to finish (drywall, floor, lights, HVAC, etc) once its enclosed.

you laid out some items that would save some expenses going the slab route, but still mention 25%. Are you saying if a ranch with finished basement costs $400k, that a slab on grade with equal finished sq ft would cost $500k?

generally speaking yes. But there are so many things that can come into play it's really hard to make a blanket statement. Just the cost of floor coverings can change it dramatically. And yes to your first question.

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basements are not tax free living space. they tax you on the sq. footage of finished living space. It all figures into your assessed value. Sq. footage is sq. footage in the eyes of the tax man. And they're so damn tax happy here now you can bet your going to get the onion.

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My personal opinion on in-floor heat in a home is it's a waste of money. You need forced air for A/C anyway. So why have both systems. The new furnaces are extremely efficient. If you want a warm floor put 1.5" foam under it. I've done that on every home I've built. It's amazing the difference.

 

[DirtyMike]

I don't know what I'd do without a basement. KDM nailed it when he said it's cool in the summer and warm in the winter.

 

[Ponyroper]

I've lived in my home now for 14 years and every time I think that I could have put it on a basement but didn't because I thought it was an unnecessary expense I bend over and have someone kick my in the butt. Laying in bed Wednesday night listening to that freakin' wind work it's way up to 70 or 80 miles an hour and sounding like a freight train coming through my bedroom I thought for the hundredth time, "Oh titty sprinkles! Here it goes!". Never, EVER, again would I build or live in a house in this country that didn't have a basement or at least a storm room below ground. Just my humble opinion.

 

[Captain Ahab]

If I did a basement, it would be 3 sided built into a hill or man up and pay for fill. The only basements I know that haven't had water problems are those types. Everybody else I know has had water problems at some point.

 

[Kurtr]

With proper water proofing and icf basement it would have to come over top the foundation to water inside. Ad drain tile and there should never be a problem. Last year I had water on all four sides of my house and the sump still has dust and spider webs in it.

 

[BrokenBackJack]

Good thoughts. Always cheaper to build up and not out.
For sure put foam insulation under your concrete and outside your concrete if you pour basement walls if not using the new insulated forms to pour your concrete basement (forget the name but mentioned above). Put in drain tile and open floor trusses as mentioned. Make the garage bigger than what you think you will ever need.
Plan, plan, and plan some more. Definitely not wasted time.
Remember to plan for an overhead fan in all the bedrooms and living room and tv areas.
Spray foam insulation is a must.
Had a buddy build a new house and he put in a low and a high air return for the furnace and a/c in every room. It definitely makes a difference. Sucks off the low in the winter and off the high one in the summer.
South facing driveway so you have no or little ice in the winter.
Plan for trees in your yard to give shade and help block wind.
Wire for internet and TV in every room and garage as not much added cost.
Put in way more power outlets in garage than you think you will ever need and also put garage on separate breaker box. Put in overhead fans in garage along with lots of lights on separate switches. Don't forget the floor drains for garage too.
Good luck!

 

[Captain Ahab]

With proper water proofing and icf basement it would have to come over top the foundation to water inside. Ad drain tile and there should never be a problem. Last year I had water on all four sides of my house and the sump still has dust and spider webs in it.

Depends on where you live and the water table. Where I am at, pretty much all basements are a heavy rain and a power outage/sump pump failure away from a disaster.

 

[Kurtr]

We are just getting done with a water treatment plant with all concrete holding tanks that don't let the water out kinda reverse water proofing. With the advancements in chemical adatives such as xypex and other water proofing materials in the future the only water getting in will have to come over the sill plate. With old houses an alarm if it goes out is a good plan I know my dad wishes he would have had one in 97.