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Discussion Starter · #1 ·
Hey guys(and gals),
I was recently doing some research on basement foundations when I visited a fairly well known site called "Ask the Builder". What I was reading didn't quite jibe with me so I decided to reply with a comment. For some reason my comment was never posted so I decided to cut and paste the page here.
I'd like to know, was I out of line here?




Crawl Space vs. Full Foundation
By Tim Carter
©1993-2009 Tim Carter
Summary: Choosing a crawlspace over a full basement is a way to save money when building a new home. However, in the long run the usable space is a good investment.
DEAR TIM: My husband and I are having a large (24x18 feet) room addition built. Our house has a full basement. Our builder says the cost to upgrade from a crawlspace to a full basement would be prohibitively expensive. Is this true? How would the two basements be connected? What could be done to water proof the new foundation? P.A.

DEAR P. A.: I don't know if I necessarily agree with your builder. Yes, there is extra cost involved to turn your proposed crawl space into a basement. However, the added cost to create usable basement space is a worthwhile investment.
From a building standpoint not much has to be done to create this space. Your backhoe is already there to dig for the crawl space. He just needs to stay for an additional 4 - six hours. There is no up charge for the footer. Your foundation walls only need five or so extra feet of height. Add a concrete floor, foundation waterproofing, and an entry opening to this new basement and you are ready to play some ping pong!
I did a quick cost analysis. At current prices in my city here is the cost breakdown to achieve the full basement:
extra excavation $250
extra foundation height $1,650
cut opening into old basement $380
concrete floor $1,050
foundation waterproofing $480
You get a $150 credit for the floor insulation you would have had for your crawl space. The total cost of the upgrade, less profit and overhead, would be $3660.
 
 
 
 
Hi Tim,
If it's ok with you, I'd like to respectfully disagree with the advice you gave P.A.
I understand this is an older post and the nice folks who originally posted are probably playing ping pong in their new basement which probably ended up costing them thousands of dollars more than the $3660 upgrade you had quoted them.
1st of all, the extra excavation time could be considerably more than the 4-6 hrs you quoted. In many, if not most areas, the further you dig down, the more rocky and slabby the earth becomes. Many times it's necessary to bring in expensive jack hammers and more labor to run them. In fact hours can easily turn into days. Then you have to deal with all of the dirt being taken out of the ground, which can cause a clogging effect on a tight space work area.
When you said it would cost less than $400 to cut a hole from the existing to the new basement, I'm wondering; does that hole go from slab to sill plate? It seems to me that a header of some sort would need to be taken into consideration so the the building above doesn't collapse or sag.
Also, I'm wondering if they are playing ping pong with flash lights or night vision goggles. Other wise they would probably need to power up the basement somehow. My guess is it would take an electrician, which we all know don't come cheap to HO's.
I would like to say that I enjoy your website and have turned to it many times for helpful insights, but I'm not sure you did the HO's or the their builder much of a favor on this one. I think you said it best when you stated, “I did a quick cost analysis”.
Again, this disagreement comes with much respect.
Rick
 

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Your points sound reasonable to me, around here we usually have bank run or clay, so the extra digging is usually not that much of a big deal, otherwise i agree, the numbers where light;). G
 

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Curmudgeon
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I'd say in principle, he's right.
I don't know about his numbers,
or how old they are, but it sure
does depend on what part of the
country you are in.
His only fault would be painting
with too broad a brush.
Did he know that the OP was in his area?
 

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Discussion Starter · #4 · (Edited)
Just a quick after thought, which I never mentioned in my reply to Tim;
If you're playing ping pong down in your basement, wouldn't most people like to be somewhat comfortable? meaning they'd need a way to heat and cool the space.

most crawls have a ventilation sytem which allows the radon to escape and the moisture to subside. I'm not aware of any basement that uses this sort of low cost air conditioning system. It seems to me that extra hvac costs would need to be considered. Not just for duct work, but also for a larger size furnace and AC and proper insulation.

by the way neo...the posts came from late 08 and early 09.
 

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Discussion Starter · #5 · (Edited)
I'd say in principle, he's right.
I don't know about his numbers,
or how old they are, but it sure
does depend on what part of the
country you are in.
His only fault would be painting
with too broad a brush.
Did he know that the OP was in his area?
Neo,
If you can get a basement done for any where close to those numbers, I'll be sure to sub the next one I get out to you. Just be aware that I'd be breathing down your neck to make sure you're not cutting any corners.

But 1st you might want to read my reply to him where I clearly spell out the potential for extra costs.
 

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We recently added on to our house and we added the basement addition too. It was worth every penny. Yes, it was a lot more expensive but like I stated, the extra play area for the kids for those days they can't go outside, are priceless.

Here we are digging the new basement:


After giving up on that sh!t, we got bigger tools...


and paid someone to do the work:

:thumbsup:
 

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Curmudgeon
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Neo,
If you can get a basement done for any where close to those numbers, I'll be sure to sub the next one I get out to you.
The mechanicals don't really add that much.
The furnace is there, the electrical is routing
through it, it isn't adding that much load
to the heat, and A/C is nearly nothing.
I have no idea where you are.
Maybe your water table is 3' down.
Maybe bedrock is 2' down.
Here we have clay for a looong way,
and a basement is the cheapest square footage
you can build. (given a crawl as the alternative)
 

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Discussion Starter · #8 ·
The mechanicals don't really add that much.
The furnace is there, the electrical is routing
through it, it isn't adding that much load
to the heat, and A/C is nearly nothing.
I have no idea where you are.
Maybe your water table is 3' down.
Maybe bedrock is 2' down.
Here we have clay for a looong way,
and a basement is the cheapest square footage
you can build. (given a crawl as the alternative)
The furnace that's there is undersized as well as the AC, the electric that's going 'through it' is actually going through the walls above the basement. And you would need a new ciruit(s) to accomodate for the minimal lighting and the recommended outlets. That is unless you're thinking of splicing from existing wires. The power at the current service panel may not be adequate.

Stating that things are next to nothing and the cheapest way to go just doesn't cut the mustard with me or most potential clients.

I'm sorry sir, please try again.
 

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Have to agree. We had to add circuits, run a bunch more duct work, get a bigger furance and so on and so forth. Still it was worth it.

Then we had to run those new ducts beside the old ones to get to the new section. I wonder if they had windows on their old basement walls they had to take into consideration? We did. It's now a built in cabinet.:whistling
 

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Curmudgeon
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The furnace that's there is undersized as well as the AC, the electric that's going 'through it' is actually going through the walls above the basement. And you would need a new ciruit(s) to accomodate for the minimal lighting and the recommended outlets. That is unless you're thinking of splicing from existing wires. The power at the current service panel may not be adequate.

Stating that things are next to nothing and the cheapest way to go just doesn't cut the mustard with me or most potential clients.

I'm sorry sir, please try again.
I have thought about it,
and I have done it, and I am sitting
on top of a basement right now.
the electrical service is down there.
It branches across the basement to
get to the walls for the upper floors.
The furnace is down there.
The supply and return trunks
cross it to get to the upper floors.
If you add space on the upper floors
you will have to up size HVAC capacity
for that.
The extra load for the basement is negligible.
But have it your way.
 

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hurtlocker
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those numbers would get you pretty close around hear
as an unfinished space
I would add ins in my area +500-1000
add for any other extras
 

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Discussion Starter · #12 · (Edited)
We recently added on to our house and we added the basement addition too. It was worth every penny. Yes, it was a lot more expensive but like I stated, the extra play area for the kids for those days they can't go outside, are priceless.

Thanks for the great pics, Cdat. Everything looks good from what I can see. Correct me if I'm wrong, but is that a lower level walk out instead of an actual true basement? Also, what material is that being used for the footing forms? just curious thanks!
 

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Discussion Starter · #15 ·
As you can clearly see it is a baby pool....:blink:

The correct question is: why is a baby pool in a cage of chicken wire? :w00t:

Only Cdat can answer that....


I think I can handle this one for ya, cdat.

The cage is obviously to keep the chickens out of the kid's pool!:thumbup:
 

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Discussion Starter · #16 · (Edited)
I have thought about it,
and I have done it, and I am sitting
on top of a basement right now.
the electrical service is down there.
It branches across the basement to
get to the walls for the upper floors.
The furnace is down there.
The supply and return trunks
cross it to get to the upper floors.
If you add space on the upper floors
you will have to up size HVAC capacity
for that.
The extra load for the basement is negligible.
But have it your way.
Lucky for you your electric service is already down there.
And your furnace too!
But this dicussion is about the extra costs for adding a basement foundation to an addition that was already planned for having a crawl.
Not the house YOU are living in.
Perhaps the furnace and electric panel are already placed in the existing structure. If the 18x24 addition is only a single story then that's more than 400 sq ft of extra living space you would need to heat, cool, insulate and power up.
Now you want to double that living space by putting in a basement and still expect your current furnace, ac, and service panel to carry the loads?

Furnaces and AC units are sized appropriately according to the size of living spaces for numerous reasons that I just won't have time to explain to you in this discussion.

The fact is the original HO's just didn't give enough details about the job for Tim Carter to tell them that for a mere 36 hundred bucks they'd be playing ping pong in their new basement.


You've got just 3 more tries on this one.
 

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Discussion Starter · #17 · (Edited)
neolitic;788521 The extra load for the basement is negligible. quote said:
I think a better way of stating this is: The excuses(or better yet, the lack of sound reasoning) I'm giving for adding the extra load to the proposed area, using the existing services is NEGLIGENT.:no:
 

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Curmudgeon
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Lucky for you your electric service is already down there.
And your furnace too!
But this dicussion is about the extra costs for adding a basement foundation to an addition that was already planned for having a crawl.
Not the house YOU are living in.
Perhaps the furnace and electric panel are already placed in the existing structure. If the 18x24 addition is only a single story then that's more than 400 sq ft of extra living space you would need to heat, cool, insulate and power up.
Now you want to double that living space by putting in a basement and still expect your current furnace, ac, and service panel to carry the loads?

Furnaces and AC units are sized appropriately according to the size of living spaces for numerous reasons that I just won't have time to explain to you in this discussion.

The fact is the original HO's just didn't give enough details about the job for Tim Carter to tell them that for a mere 36 hundred bucks they'd be playing ping pong in their new basement.


You've got just 3 more tries on this one.
neolitic;788521 The extra load for the basement is negligible. quote said:
I think a better way of stating this is: The excuses(or better yet, the lack of sound reasoning) I'm giving for adding the extra load to the proposed area, using the existing services is NEGLIGENT.:no:
This was the original premise.
"DEAR TIM: My husband and I are having a large (24x18 feet) room addition built. Our house has a full basement. "
 

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Curmudgeon
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Your points sound reasonable to me, around here we usually have bank run or clay, so the extra digging is usually not that much of a big deal, otherwise i agree, the numbers where light;). G
those numbers would get you pretty close around hear
as an unfinished space
I would add ins in my area +500-1000
add for any other extras
Lucky for you your electric service is already down there.
And your furnace too!
But this dicussion is about the extra costs for adding a basement foundation to an addition that was already planned for having a crawl.
Not the house YOU are living in.
Perhaps the furnace and electric panel are already placed in the existing structure. If the 18x24 addition is only a single story then that's more than 400 sq ft of extra living space you would need to heat, cool, insulate and power up.
Now you want to double that living space by putting in a basement and still expect your current furnace, ac, and service panel to carry the loads?

I would expect that one would be sizing
mechanicals accordingly and consider the
basement at the same time as the additional
main floor space.
But that's just me.
Furnaces and AC units are sized appropriately according to the size of living spaces for numerous reasons that I just won't have time to explain to you in this discussion.

The fact is the original HO's just didn't give enough details about the job for Tim Carter to tell them that for a mere 36 hundred bucks they'd be playing ping pong in their new basement.


You've got just 3 more tries on this one.
Look at it like this.
You are already paying for everything
from the frost line up.
That is the expensive part.
Going 4' down from the frost line is
peanuts by comparison.

Seemingly you don't like basements.
Maybe you have permafrost where ever
you are.
 

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Discussion Starter · #20 ·
This was the original premise.
"DEAR TIM: My husband and I are having a large (24x18 feet) room addition built. Our house has a full basement. "
We can all see that.
What it does'nt say is: Neo's house has a full basement with a furnace and service panel already down there.

What you seem to be having a hard time understanding is that the discussion is about the extra costs of adding a basement foundation(as opposed to a crawl foundation) to a proposed addition.

What makes you think the furnace and service panel are down in their existing basement?

Even if they were, it still doesn't explain how you're going to heat, cool, insulate, and power up the new basement at no additional costs.

I can see where there is sort of a brick wall seperating you from the dilema, so I'm not even going to count this one as one of your last 3 tries.;)

Another point not being taken into consideration, when it comes to extra costs, is the difficulties of waterproofing and maintaining a dry environment in an underground basement, as opposed to crawls.
The footings for a crawl space foundation need only be a couple of feet below the ground surface level in many areas, in order to protect it from freeze/thaw contractions. At this depth, the amount of water forcing its way below the footing and into the structure is quite managable.
Not so much when placing your footings an additional 5-7 feet below the ground where the water table has a better chance of encroachment. This is especially true after a big rain.
Think of it this way: the deeper you dig a well, the better chance of hitting water.
So how do we contend with this encroaching water? There are many ways that I know of that I'd be happy to dicuss in another thread if anyone was so inclined. Bottom line here is-none of them are cheap.

Again, I think Tim Carter did nothing for the original HO's except get there panties soaked over the thought of getting a new basement for a few extra bucks.

Maybe if we say Tim Carter enough times in this thread, he'll google himself and end up here explaining his own actions and thoughts.
 
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