Price for taller (deeper) basement
 

Hi,
I am starting the process of figuring out what we want/don't want in our next house. The development we have been looking at (sorry, the contractor for the development) wants $3950 extra to make the basement walls 1' taller (or deeper depending on how you look at it). That, to me, seems really high. This is in the midwest if that helps. The builder has done this in the past so I don't think he was giving a high price to talk me out of it. What do you guys think?
scheu

There is a difference between 1' higher & 1' deeper
1' deeper means more digging
What size is the foundation ?
How much is in the ground...how tall will the concrete walls be ?
Concrete is expensive

This is a DIY site, local prices are best. We can tell you how to dig it........

Be safe, Gary

Thanks guys. I'm not looking for a quote really, just interested if that figure is out of line. Scuba Dave, when I was talking to the contractor/salesperson, he said taller walls, so I'm sure it's not actually "deeper" only taller, total floor to ceiling of 9'. I'd bet the same amount is under grade as the 8' would be.
scheu

No way to tell if the figure is out of line
For a 12x24' foundation it might be high
For a 36x100' foundation it might be a great price

Guess I should have given more details. Sorry. The plan is 1341 sf, full basement, overall dimensions are approx. 52'x28'.

Based on your dimensions, you have a total of approximately 150 linear feet of wall. Assuming an 8 inch thick wall, that is 2/3 of a cubic foot of concrete per linear foot for an extra one foot tall, which is about 100 cubic feet of concrete, or approximately 4 cubic yards. When you go from 8 to 9 feet you pay a premium for the forms, since they are taller than normal, however $4000 for 4 cubic yards seems to be very high. In commercial work, we often figure about $250 per cubic yard of concrete in place.

Of course, if the contractor has to dig deeper, that is an entirely different situation.

Scheu,
I would venture to say that if you are raising the height of your basement, it will go deeper in the ground. I built houses during the 90's up till around 2004. Normally when you submit plans for approval, you are also required to submit a plot plan of your lot showing the footpring of the building with elevations from a known benchmark. These elevations would include top of basement footing, top of foundation, etc. The city engineer reviews these and adjusts these finished heights if necessary to suit the lot. If you are on a street with neighbors, they look at the finished heights of those foundations in relation to what you are proposing so everyone's lots can be properly sloped and swaled for proper drainage.
Mike Hawkins:)

:yes::yes::yes:

Often times an 8" thick, 8' wall becomes a 10" thick wall at 9' tall. Quite a bit more concrete at this point, as well as insulation, excavation, backfilling, stone for backfilling garage & stoops, etc......

Could be that the foundation contractor only has 8' tall forms as well, and needs to stack fillers on top of those forms for the additional foot, which can be very time consuming compared to just setting 9' wall forms.

Everything in construction is always way more expensive then you think. Considering the extra cement used, the extra labor, that probably seems about right. To put it in perspective, how much does the whole basement cost?

For fun ask him how much it would cost to go with cinder blocks instead. I've heard of people actually choosing this over poured cement. It's probably way cheaper, and if it's done properly it can still be a very good foundation. Not sure how often it's actually used now days though.

We built a house in Omaha, NE a few years back. It was around 1300 sqft on the main floor, and had a full basement. We asked the salesman(!) to add one course of concrete block to the basement to raise the ceiling 6". He said that was easy, and only charged us $100.

Adding the one course of block was the easy part. Because they didn't dig the basement any deeper, the house sat further out of the ground. The front of the lot sloped gently down. They had to use almost double the amount of veneer brick on the front of the house. They had to add steps and railings to the front porch steps. The steel support columns they had were too short, and had to be replaced. The furnace ducts were too short. On and on.

On the plus side, we could ski down our driveway in the winter.

There are lots of things to consider when raising the ceiling in the basement. $4000 seems like a lot, but it sounds like your builder has a handle on the ramifications.

along in the same vein as firehawk; if the plans need to be recertified by an engineer, that's going to cost some money as well.

Around here if you were using ICF blocks and wanted to add another row of blocks all around for height, that would be around $1500 for that size house including concrete..

Why dig down for basements?? Raised basements are the way to go, build up not down. Im guessing if its formed concrete foundation the contractor only has 8' forms.

But still i thought it was a recession in the USA. Call around!

as firehawk stated, the height of the overall building may be important to the situation or the amount of basement wall exposed could be important as well.

I'm betting that the contractor has 8 ft forms and would need to build them taller.
If that is the case, the price sounds reasonable. Labour isn't cheap.