Whats is an "EXPANSION JOINT", when dealing with concrete.?

Question

My inspector wrote a note stating i need an expansion joint around foundation where new concrete will come in contact of home. So what is this expansion joint and where can i get some?

Answer 1

it,s a cut or a break in the concrete

Answer 2

In concrete floors and pavement, expansion joints are typically cut every 10 - 20 feet. IF they are not cut, the concrete WILL crack (probably where you least want it to). It cracks because of expansion and contraction due to temperature, also ground movement. IN some cases the joint is made with the form ussed to pour the concrete (wood or plywood).
Typically, the cut is 3/16 - 1/2 inch wide and ALL the way thru (some contractors cheat and cut only to a certain depth (the concrete cracks the rest of the way by itself as I said above). Then backer material is stuffed in followed by a self-leveling polyurethane sealant. On traffic surfaces the expansion joint can be engineered with a purchased or custom manufactured rubber assembly and glued/sealed into place. I am not familiar with joints you can buy at Home Depot of Lowes, etc. Other types of sealing can also be used inculding a rope type of caulk. The sealant prevents water from getting into and beneath the concrete and rusting the rebar or doing other mischief (eg. weeds). It also prevents gravel from getting in and causing cracking. HIre a contractor to cut one for you or rent your own concrte saw. The ones which can be used while you are standing.

Answer 3

Expansion joints are physical separations between two masses of concrete. The ground around your home is constantly moving and shifting. If there is concrete above this earth, then it will be moving also. If the concrete is poured right up to the slab of your house, the concrete will buckle and crack. A piece of treated wood, positioned between these two masses of concrete, will allow each to move independently of each other. Eventually the wood will rot out, or get loose and work itself out of the joint. There is also another type of material used for expansion, that is made of a fibrous material, that doesn't rot. I hope this helps!

Answer 4

When concrete under goes heat and cold it expands and contracts.So to keep it from rubbing against what ever it is in contact with and causing it to crack or wear away they put in a space filled usually with a rubberized fiber that keeps the two apart.It's used in driveways, sidewalks and even roadways. You'll also see expansion joints on the end of bridges.You can pick up the expansion joint filler at your local lumber store.

Answer 5

It isn't something that you go out & get. It is a space between two masses of concrete that meet up that allows for the expansion & contraction of the concrete.
If there was no expansion joint & the concrete slab expanded against another surface, it will bulge & crack.

Answer 6

It is the joint they put in between pieces of concrete that will be exposed to heat or cold and when they change temp it keeps them from cracking

Answer 7

a expansion joint is a peace of material treated with waterproofing about 1/2 inch thick that allows the con create to expand with out pushing on an other object and damaging it. they are available at any building supply store.

Answer 8

an expansion joint is the crack/space that is between your concrete and the foundation of your home. it is not something you go out and buy..........