# basement under double wide



## lamina1982 (Jan 14, 2013)

i have a "77 doublewide currently on a block foundation-may 6 blocks high. the crawlspace is probably only a foot or 2 below grade but yard slopes so dirt goes up a little more on the sides. I have wanted to have a basement put under the home-i figured just going up would be more economical than digging deeper. However afte this winter one part of wall cracked some blocks in half (outer half) below one of the steel i beams and bowed in some..noticed right when all snow melting and now that grounds back to settled the wall evened out. if you look in crawlspace it apears to have a poured footer. however i have noticed that on one end the corners are not below grade and i can stick my hand up into the space in the blocks..so not really sure what the footer is actually doing if the blocks are not setting on it??
So i am guessing that i could not build up and the whole thing would need replacing. at least house has not settled or anything like that. i plan on having someone doing the work but how feasible is it jacking up the home and having a basically at grade basement put under it? and would blocks or poured concrete be stronger/more stable?
its roughly 25'x40' with ibeams longways and shortways


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## T-Bone 369 (Jan 18, 2007)

Some pictures would really help but if I read this correctly you have a couple issues.

1. The bow in the wall was probably caused by frost in the ground. Block are extremely strong in compression (down pressure) but have very little strength against lateral force. That's one of the big reasons that block basements fell out of favor. Make sure that the ground is sloped away from the foundation so water runs off and that will help but in all honesty once this is started it probably is going to be a recurrent problem. If you look at the mortar joints in this area your probably going to find cracks that work their way up the wall near where the ends of the bulge was. Over time these will get bigger as the wall works through freeze and thaw cycles. They can be tuckpointed but this is only a cosmetic fix. 

2. The top of the footers being exposed is not that big of a deal - it is the bottom that is of concern. From the sounds of it they poured a trench footing, basically dug down (hopefully) below the frost line then poured the trench full to the top with concrete. Nothing wrong with this as long as they are below the frostline. 

3. If you have a gap between the block and the footer (if I read this correctly this is what you are saying) then it would appear that the footer is sinking. This is probably in a corner - essentially the footer broke and is sinking into the ground faster than the rest of the footer. When you talk about the block being cracked in half I assume this is in that area. That would be typical of unsupported masonry - without the footer under the blockwork the weight of everything above is cantilevered. When stressed in this way block typically have a vertical crack fairly strait up and down usually about four inches from the end running into the head (vertical) joint in the course above then into the next block. Over time this will open up. You can tuckpoint between the block and the footer - this will be help but is a temporary fix. Sometimes over time the settling will stop but until and if it does this is going to cause you problems. 


As to a basement, from a cost point probably the most efficient way to do this would be to have the unit moved. Working under a home is going to get real expensive real fast. I know of several basement that have been dug under existing homes - it is almost all hand digging. Read labor intensive. Since this is a designed to be moved you could have it shifted off the existing foundation so an excavator can get in there with big equipment to remove the old foundation and dig a new basement. I would go with poured concrete walls over block. It is possible, if you have the space, to have the new basement dug in a location near where the unit is now then move it over. That would save the expense of having the unit moved twice (once off and once back on). Any way you go about this it is going to be an expensive job. 

Tom


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## Xperthunter (Mar 30, 2015)

Just a thought. My house was at one time a 50x24 manufactured set on a basement. Have you considered digging and looting the basement then having your house moved on top of it. Would be a simple matter to move/extend the utilities and remove the old wall and reseed


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## mreynolds (Jan 1, 2015)

Just an idea but I worked on a trailer house once that had a basement added directly behind it. Then they built over the top of it and effectively doubled the size of the house.


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## mreynolds (Jan 1, 2015)

Xperthunter said:


> Just a thought. My house was at one time a 50x24 manufactured set on a basement. Have you considered digging and looting the basement then having your house moved on top of it. Would be a simple matter to move/extend the utilities and remove the old wall and reseed


Thought about that first but then I figured you would have to change the floor plan up pretty much to add a stair down to it. Most trailers have all space utilized for something so that might be a task to do.


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## lamina1982 (Jan 14, 2013)

trouble with moving or doing basement then moving is the wells in front yard and septic behind it so not sure how much room id have. also i dont care if the "basement is below or above ground. As in wouldn't really need to dig down except for footers etc i think. Ill try and post pics to show what is there currently.

my plan was if built the basement -down the road if home starts dieing (particle floors etc) could live in basemen as built up a standard stick frame


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## lamina1982 (Jan 14, 2013)

Heres aome pics
Ariel of property layout









Some crawlspace pics..hard to tell but the wall was bowed in here and the blocks below the ibeam were crushed some..the outer surface of the block broke off. Can see a footer here but it doesnt appear to extend to the outside edge of the blocks..which would seem weird. I am guessing has been this ways since 77. The crappy part is i had to pay extra for an "engineer" to inspect it and get pproval for mortgage..but not even a year in get this weird damge plus who knows if built correctly. Im sure was frost as had a big lump grow in rd this winter...plus once ground thawed the bow in block wall dissapeared


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## Fishindude (May 19, 2015)

Adding a basement in the present location is going to be very difficult, and very expensive unless you have the ability to do it all yourself and don't mind a really difficult job. Imagine, just trying to dig that out with the house in place?

What you have can probably be pretty easily fixed by putting some new load bearing piers of concrete, treated lumber or special screw jacks under those beams to pick up that load. Then it would simply be a matter of patching up the cracks in masonry and leaving it where it's at, forgetting about the movement, bow in the wall, etc. There is a company called AccuLevel that does those screw jacks.

Looks like you have room to move the house south? Could build a new foundation / basement close to and in line with existing, then slide the house south onto new basement and demolish the old. House movers and modular home guys can do this pretty slick with beams and rollers. You would also have some utility extensions to new location to deal with.


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## beenaround (Mar 2, 2015)

it's a double wide and rests differently, the block wall needs to be nothing more than a skirt. With a house the perimeter needs supported.

That is good news. Jack the thing up, put the supports where they need to be and start digging. Old school was to use horse and scrape bucket, bobcats today. Shouldn't take more than a couple hours to dig.


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