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Removing part of concrete sidewalk
Aug 11, 2012, 02:36 PMpree987
Removing part of concrete sidewalk
I'm gearing up to start my first project in my new house, a new patio. There is currently a concrete sidewalk that runs around the perimeter of half of the house, right up against the foundation.
I want to remove part of the sidewalk so the patio can go right up against the house where I plan to build it. It looks like the concrete is about 5" thick, so I'm thinking about renting a concrete wet saw from Home Depot to make a clean cut, and then a jack hammer to break up the pieces that will be removed.
Is there anything I should be aware of when doing this? I've never cut concrete before. I'm also wondering if it will be a problem that the sidewalk runs up against the foundation of the house..
Aug 11, 2012, 02:53 PMJaybee
You've got the right idea as to what tools are needed to do this. If you rent a concrete cutting "quickie saw" make sure you to two things:
1. Get a gas powered model. The electric versions are really wimps compared to the gas models.
2. If it doesn't come with a diamond blade, spring for the extra $ to rent that too. The standard composite blades don't last very long.
It's hard to make the call as to if a sidewalk that is up against the house will cause any problems if removed. Usually, it's a bad idea to put a slab of any kind right against the house as any settling in the slab will make a backwards slope to gather water. As long as your new project doesn't direct water to the house or create a dam to hold water there, then it should be OK.
Aug 11, 2012, 05:18 PMNestor
Of the gasoline powered concrete saws I've seen, NONE of them will cut to the end of your sidewalk slab without also cutting into your house's foundation.
I think you need to buy or rent a long solid steel pry bar called a "lining bar":http://www.industryrailway.com...inch_point__300.jpeg
...as these are what railways use to move rails before nailing them down, and pull rails off of rail way ties. THAT is the kind of pry bar a person needs to move an 1800 pound concrete sidewalk slab.
Set a piece of lumber on the ground to use as a fulcrum. Get the business end of the lining bar under one end of the slab and lift that end a few inches. Then, swing the other end of the lining bar toward the house, causing the business end of the lining bar to move that end of the slab a few inches away from the house. Repeat at the other end until you get the slab a foot or so away from the house so that you can cut through it completely with your saw.
I'm not a fan of having any kind of sidewalk or concrete slab right next to a house. Where I live, the ground freezes in the winter down to a depth of 5 1/2 feet or so. At the frozen/thawed ground interface, water percolates up from below and freezes to the underside of the frozen ground. As that water accumulates and expands as it freezes, it forms ice "lenses" in the ground, so named because their profile is thinnest at the exterior and thickest at the middle, much like a magnifying glass lens.
Those ice lenses expand with tremendous force, and they can easily lift a concrete slab, causing the slab to rub against your house's foundation on the way up, and again in spring when it's on the way down as the ice lens melts.
So, if you want the sidewalk to come up right ot the side of your house, maybe put some stainless steel sheet metal between the foundation and the slab so that the slab doesn't scratch the "parging" (I think it's called) on your foundation.
Aug 11, 2012, 11:42 PMjoecaption
When poring the new slab prep work is 90% of what's going to make it last.
I strong would suggest you hire it out.
What your looking for a company that does concrete finishing.
Make sure it slopes away from the house.
Make sure it's at least 4" below and door thresholds. (very important!)
This is gong to be a one shot deal so think the whole plan through before doing anything.
Are you going to want to add a roof later?
Are you going to want to enclose it later?
If you plan for these things ahead of time it will be far cheaper to add the footings for post or building it higher so water does not come in under the walls.
Check around on this and other DIY sites. There's hundreds of people dealing not liking the look of the concrete patios and want to go over it with something to cover it.
Why not plan for that and go with a stamped slab, exposed agragate, or even stained.