# need the how-to's on "backfilling"



## theemon (Jan 14, 2013)

when the the time comes(this spring) i need to know the ins and outs on backfilling around my house. heres why


my house sits on the side of a hill, slowly pushing down(i guess???) well the house has the orginal foundation, then an added 6-8ft extension, this extension basement wall was backfilled with, well everything, brick, cinderblock, clay pipe, big rocks etc... then dirt.. it busted in the extensions back wall, so i need to know how to back fill it once fixed... from science class i realize all these pointed objects caused pressure spots that pushed in the cinderblock wall, so obviously no big pointed objects,

what do i backfill it with? the surrounding dirt? or TONS of gravel? what about the hill pushing?

if it maters i plan on puting french drain pipes all around the house... but is it effective 5ft below the ground?


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## rhome (Aug 10, 2006)

There're some critical steps and materials/fill for backfilling. Sorry I don't have any details.
A good source might be Taunton Press, Fine Homebuilding books and magazine.
I recall an illustrated article about backfilling a basement wall a few years ago.


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## blooba (Feb 9, 2010)

The biggest force against a wall isnt the dirt itself its the water so if you can keep the water away you will eliminate most of the pressure. your going to have to use alot of gravel for drainage around that french drain.


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## TNHermit (Jul 14, 2005)

Make sure you have tile and good drainage. You back fill with #2 then #6 stone about 3 ft away from the building. Pressure on stone is always down not sideways. If you have horizontal cracks now that is where the frost line has been. NEVER back fill with dirt or clay. You can use it the last foot or so.
If the ground under the foundation is moving then there si nothing you can do


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## RonM (Jan 6, 2008)

Make sure the roof is on and siding is on before you backfill, to give you the added weight.... I saw a guy backfill before this was done and his basement caved in, his dad said tohim , I tried to tell you to do that first, but you wouldnt listen......


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## motdaugrnds (Jul 3, 2002)

I learned the hard way in that a couple of "professionals" built me a retainer wall with cinder block, back filling it with the dirt they dug out. It fell down inside a year! I had to take out all the block, dig the soil down a bit and replace the block leaving about 8" on the back side for fill. Yours will be different in that you really need a way for the water to drain out and away from your house.

Digging all that crap out will be hard enough; but securing your roofing/walls (as suggested above) will be a must if you're going to be successful. Then you need a trench deeper than the foundation of your floor for run-off water to collect. It should have the "small" rock (like the #57) filling it. Then lay a perforated pipe with holes pointed down on top of that gravel. Then add another batch of same rock, place some sheeting over all that to deter any soil from getting into the rock but that will let water thru. Then cover entire trench. (That should have been done when the house was first constructed instead of all that junk you said was used as fill.)


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## theemon (Jan 14, 2013)

motdaugrnds said:


> Then lay a perforated pipe with holes pointed down on top of that gravel.


why down?



and for the 5ft or so above the pipes what should i use? gravel? id have to buy that.










also how hard is it to build a 10ft retaining wall, agaist a road?


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## motdaugrnds (Jul 3, 2002)

theemon said:


> why down?* You want the water in that trench to get into the pipe and run on off. (It is my understanding that laying the holes down helps best with that.)*
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> 
> ...


 *10 ft high would be terrible! 10 ft long would not be difficult at all. You simply need to know how high you want it to be; and if it will be over two cinderblock high, you would need to use something to stabelize it to the existing soil about 10 ft back. *

*Let me tell you what I did .. as cost effective as I thought would work: My retainer wall runs the length of my drive between the yard of my home and the barn, then on around the back yard down to the buck house in the back of my 6 acres. *

*I did the part around my yard with cinder block, making it tall enough to level my yard, which was 5 blocks high in some places(with one block being in the ground). Each row was altered so the next row of block would sit on "half" of the two block under it. As I went along, I would fill the blocks with small rock/soil/even quickrete; and every 3 blocks I added a 10' rebar ("Z" shaped meaning we bent it down about 4 inches on one end and up about 4 inches on the other end). One end of the rebar I placed into the next to the top layer of block (cementing it into join the two layers of block); and the other end of the rebar I "buried" in the ground under another cinderblock (cementing it in) as far up into my yard as it would go. [All rebar got buried into soil and grass over it.]*

*I had to circle some trees; so keeping the wall straight and solid took some strategy.*

*The part of my drive down nearing the buck house, I used wood. I placed 6x6x4 treated posts in the ground every 3-4 ft; then attached treated 2x6s on the high side up high enough to level my drive. Then I had some very large rock brought in and dumped, placing them by hand all along those 2x6x; then had some #57 rock spread down that drive. (This year I'm spreading some crushed stone as I don't like using #57 on a drive!) I specifically used rather tall 6x6s because I wanted more than just level ground there. I wanted a 4' fence as well!*

*Hope this helps...At least it may give you some food for thought...*


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## theemon (Jan 14, 2013)

i ment 10ft high, if not more... my whole yard slopes downward into the road, wasting more then half my yard


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## motdaugrnds (Jul 3, 2002)

Theemon, I would NOT make one 10' high retainer wall. Instead, I would create several rows of what I call "terracing" all the way up to where I wanted my yard to end. Then I would make that one retainer wall just high enough to level my yard. Yes it would be a lot of work and costly; but I can just see a 10' wall falling over and someone getting hurt. (Remember your "right of way" on that road is going to come into play too with "legal" ramnifications.)

You can plant whatever you want on each terrace to help retain the soil and create gardens/orchards/vineyards...OMG at the possibilities!!!


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## theemon (Jan 14, 2013)

motdaugrnds said:


> Theemon, I would NOT make one 10' high retainer wall. Instead, I would create several rows of what I call "terracing" all the way up to where I wanted my yard to end. Then I would make that one retainer wall just high enough to level my yard. Yes it would be a lot of work and costly; but I can just see a 10' wall falling over and someone getting hurt. (Remember your "right of way" on that road is going to come into play too with "legal" ramnifications.)
> 
> You can plant whatever you want on each terrace to help retain the soil and create gardens/orchards/vineyards...OMG at the possibilities!!!


do tell do tell..............

im not sure how or what to do about the hill side.


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## Gray Wolf (Jan 25, 2013)

In many jurisdictions any wall higher than 4' has to be an engineered wall with tiebacks and an interlocking system for the blocks. Even if not required it's a good idea.

Check codes and good sense for the need to put saftey railings on the top of wall(s).

Don't drive heavy equipment next to the wall to level or compact the backfill or the extra weight could collapse the wall.

Put a membrane of some sort on the outside of the wall before the perforated pipe footing drain and gravel are placed.

If for a foundation, place the floor joists and subfloor first to strengthen the walls.

Soil type of what you are retaning also factors in. Clay or sand? Wet and heavy or well drained?


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## fishhead (Jul 19, 2006)

What state do you live in?


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## theemon (Jan 14, 2013)

ohio.


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## motdaugrnds (Jul 3, 2002)

Would be interested in seeing pictures of what you decide to do.


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## GoldenCityMuse (Apr 15, 2009)

Cinderblock is not very strong. A 10' high retaining wall would need THICK reinforced solid concrete poured. As mentioned, it needs to be engineered. 10,20 30 tons of weight or more.


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## theemon (Jan 14, 2013)

motdaugrnds said:


> Would be interested in seeing pictures of what you decide to do.


ill diffently keep you updated  i dont honostly know what im doing yet...


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## blooba (Feb 9, 2010)

I would 2nd the terracing on the 10 ft retaining wall. I built a 6ft tall railroad tie retaining wall once using tiebacks and a ton of rebar. Although I didnt use a drain pipe or gravel (definitly would have helped) Well needless to say it came down. :smack lol......wont be doing that again.......that was before the wonderful knowledge available on the internet


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## theemon (Jan 14, 2013)

HuskyBoris said:


> in the picture you can see a roof,this is our"basement house",.my wifes dad built it but didn't use rebar or back fill on the backside and onne spring the milk truck was backing up and the wall split open.
> now the opening is almost 4 inches and the roof has slid forward 6 inches,it is coming down soon eother by my hand or it's own.
> ithink the only thing holing it sill is the interior walls and I would like to salvage the lumbar but I need to figure out a safe way to do it.
> another option we thought was pulling the wall back with cables and steel bracing but without rebar in the walls it would be a wasted effort.I don't know if this helpd any but thought it might.


make your own thread


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## motdaugrnds (Jul 3, 2002)

Theemom, I interpreted HuskyBoris's post as letting you know what he did wrong, which, in my way of thinking, is something I would have appreciated knowing.


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## seven7seven (Apr 29, 2013)

Without a doubt,
Install a foundation drain, covered in 57 stone gravel and wrapped in filter fabric.
Paint walls to be backfilled with bituminous coating to waterproof.
Install either a drainable foundation fabric on the wall and backfill with native soil tamping every foot. OR backfill with a one foot wide section of 57 stone with filter fabric to one foot below finish grade. Cover in fabric and top with 6" of structural native dirt fill and 6" of top soil.

Never build a retaining wall from block that wasn't designed to do so , especially 10'. Use either terracing as stated or stone gabions.

With the gabion, you can use native rock or have rip-rap delivered to you and build as you go. Looks cool too.


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## seven7seven (Apr 29, 2013)

Btw holes down on the foundation drain


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## theemon (Jan 14, 2013)

777, I hate the look of that pic. theres a lot of those around creeks n stuff here, they just house snakes.

im not sure what im going to do, right now for the next few years atleast, I turned the steep slope into a garden area , im thinking of putting two 5ft retaining walls, stepped like, with a garden inbetween.


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## wannabechef (Nov 20, 2012)

Depending on your location, a 10' retaining wall may require an engineers stamp. Check before building.


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