Foundation questions

[CurlyDave]

Another possibility is to completely enclose the space under the deck, i.e. make it part of the basement.

If you did this, the new footer directly under the outboard side of the deck would need to be below the frost line, but the existing footer under the existing edge of the basement would now be under heated space and would not be subject to freezing.


It seems to me that enclosed basement space is more valuable than space under the overhang of a deck anyway...

 

[skidoo]

Another possibility is to completely enclose the space under the deck, i.e. make it part of the basement.

If you did this, the new footer directly under the outboard side of the deck would need to be below the frost line, but the existing footer under the existing edge of the basement would now be under heated space and would not be subject to freezing.


It seems to me that enclosed basement space is more valuable than space under the overhang of a deck anyway...

That is sort of along the lines I was thinking, essentially expanding the basement area too. But, I wasn't planning on heating it. My existing garage on the other end is not heated. On a few occasions, the cat's water bowl has frozen in the garage...

I am planning to excavate down to the existing footer and pour new ones at that level for the retaining walls on the back and side. So, it is just a matter of deciding at what level the floor will be. If enclosing the front will make a significant difference even if not heated, then maybe I should consider that more. Access to that entrance will be first under 10 ft of uncovered deck out front. And, there would be no other access from the house, unless I was able to cut a doorway in the existing concrete side. I don't think I would like to do that! But, maybe there are ways to do it safely and that would be fine.

I intend to ensure that there is positive drainage away from the house everywhere. A second project is to regrade the back to ensure that proper drainage. As you can see in one of the pictures, bad drainage lead to erosion at the corner underneath the sidewalks and the sidewalks have dropped toward the house. Its been like that for at least 20 years. Never did like it like that, but always put it off for a later time. Well, that time is now coming up!

 

[rimshot]

<<Another possibility is to completely enclose the space under the deck, i.e. make it part of the basement.>>(curlydave)

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The only problem I can see with that,Dave is coming up with a roof line. Look at that picture showing the front elevation of his house, he currently has a sliding door at the second floor level and I think he is going to want to keep his deck space to be able to keep egress at that level. Perhaps he should consider two levels then or end up stuck with a darn flat roof and it still looks to me like any garage door entrance at that level would have to pitch down to floor level. I don't know if you were planning on keeping a tractor down there or not but if you are eight foot garage door heights are nice considering ROPS requirements and that might be hard to come up with RO height for a header given this plan.

If however you could make this work,it could eliminate any previous concerns about that existing footing level. My vote for skidoo now is to hire an architect and work this out. The roof line has become a problem now. Just hate throwing cold water on this and there has to be a way.

rimshot

 

[skidoo]

I am putting a new metal roof on the house as well. The roof line over the Sun Room will be an extension at the Gable end. So, the space underneath will certainly be covered. The roof line is straight and simple.

 

[skidoo]

Perhaps another picture would help the visualization. This is how it was. The Deck was removed and the Tree next to it was removed. I will essentially be re-doing it to a similar layout, but lengthening the space to 15 ft from 10 ft, and the space above will be enclosed with lots of glass. The end will be about at the right edge of where that tree was. The deck space out front will remain open but extended to 10 ft in the front. I have been thinking if I could make the space underneath very similar to the garage space on the left. It has the 8 ft height...

I have presently been parking my 2520 under that space with the ROPS down. But, I could only go back half way due to the slope. But, that was enough to cover the tractor.

 

[skidoo]

The weather has been cold, snowy, rainy, etc... So, I tried out this Sketchup program and drew what I think I would like it to end up like.

It was muddy out this afternoon and the wife says "get to digging" or else... She can't wait any longer. So, I dug down to the footers at each corner to see how far down they were.

So far, it looks like these footers may only go down to the basement floor level !?!?! Well, the house has been here for 35 years and I haven't seemed to have a problem. I know it has been down to -40F here in 1989. One potential positive is that the dirt that came out was very dry and power like, almost like an absorbent power... Is it possible that if the dirt remains dry enough that the footers don't need to go very deep?

The dirt under the topsoil elsewhere does seem to be dry and powdery just like this. My neighbor had his own open gravel pit probably 1/3 mile away, and the well has to go down 200 feet...

My concrete and framing contractors think this is doable. What do you think? Any other considerations I may have missed?

 

[ScottK]

If the dirt is dry then it can't heave in the cold.

 

[CurlyDave]

My neighbor had his own open gravel pit probably 1/3 mile away, and the well has to go down 200 feet...

My well is 700 feet, and I get lots of mud on the surface in the winter. Fortunately, the frost line is less than 12" where I live, so I don't need deep footers.

 

[skidoo]

Thanks Scott... That is what I would have thought. It sure would be nice to have others confirm that opinion. But, this thread has generated little response. Oh Well...

Anyway, my contractors seem to think it will be fine and they like the 3D sketch I drew. Finally, after the wife was able to see the sketch, she could visualize it and agrees. Before that, she just could not visualize by looking at painted lines and stakes.

So, we decided to go forward with this. Unfortunately, or fortunately (depending on how one looks at it), this is an evolving plan. For example, we have decided to have the full space underground, but that was not the primary purpose of this project. So, I am still debating on how to best use the space. I could use it as a second garage to collect stuff, dedicate it for some parking of small tractors, or a car, or a separate work shop from the other garage, i.e. one for metal work and the other for wood work, or I am thinking it would be great to function as a root cellar. I think I will start a separate thread on that idea.

Here is the progress so far. My concrete contractor wants the trench for the concrete forms about four feet deeper than the existing floor in the back, side and front. He says he wants it that deep not necessarily for frost, but for strength due to the amount of dirt being held back.

 

[radioman]

skidoo- after seeing the cad drawing, I agree with your contractor. You definetly need to have deep footings for the back/front and side walls to hold back the dirt. If you don't, you can get some cracking in the walls without the deadmans posts installed. SO getting a deep footing will help with stablity just like a regular basement to hold back the dirt without deadmans posts. deadman post is meant only for wood or rock walls, not concrete walls like the ones you are proposing. Good luck and keep us posted of the progress. I think it will come out nicely as the cad drawing you have.