Garage slab question....Construction folks?

[george graves]

So - I've got this one car garage. Finally got it cleared out of all the boxes from moving (you know how that goes)....









Anyways. The garage was built with a poured foundation around the premiter of the garage, and then years later the floor was poured. I'm not sure why, but they left a gap between the floor and the wall foundation - right down to the dirt. Not sure why they did that. It's kinda annoying. It just collects dirt and a great place for screws to be lost for ever in. So anyways...

So - is there any reason I can't fill that gap with concrete?

The only thing I can think of is expansion and contraction of the slab - but I can't see that as being a problem...it seems many people have a dirt floor basement and then finish it off with pouring concrete wall to wall. Or do I need a expansion joint all along the edges?

Anyways - my plan is to fill in the gap, then refinish the slab with self leveling concrete. Maybe paint it - maybe use some garage flooring.

[e30vert]

A: Isolation/Expansion Joints: Isolation joints are used to relieve flexural stresses due to vertical movement of slab-on-grade applications that adjoin fixed foundation elements such as columns, building or machinery foundations, etc. Expansion joints are used primarily to relieve stress due to confinement of a slab. If the slab is placed adjacent to structures on more than one face of the slab an expansion joint should be placed to relieve stress. For example, if a slab were placed between two buildings, an expansion joint should be placed adjacent to the face of at least one of the buildings. Confinement on three faces would normally be handled by placing expansion joint on all three faces, and confinement on four faces should be isolated on all faces. This allows for thermal expansion and contraction without inducing stress into the system.

As the picture indicates one can fill with expansion joint sealing compound to make that joint less visible and then just use a good flooring epoxy over the top. Its a kinda rubbery substance that stays pliable and maliable.

Another thing to do if you are concerned about it is "contraction" joints which will inhibit cracking of the slab. Take a standard Radial Saw and get a masonary blade . Then after installing it set the guard so that the blade will cut a 1/4 of an inch minimum (deeper is alright) or so into the slab. Mark some lines with a long board or just place the saw next to the long board after it has been squared up and run some cuts across the slab.

[F34R]

1+ on above, this is the edging we do on all our floors for customers.

[george graves]

Hmmm. Think I need it? Even on a one car garage?

What's the expansion material made of? What do I ask for at the home super store?

[e30vert]

Thanks F34R!

http://www.capitalmaintenancesupply.com/joint-filling-materials/

Its a polymer compound typically that allows the slab to still expand and contract as needed and not pass those stresses onto the structure. Whats nice is its a sealant and can be topcoated with garage floor paint so it does away with that unsightly border line that goes around the perimeter of the garage. Once filled , cured and then top coated it is much less noticable and yet functions in the way intended to relieve stresses.

If you search the web for expansion joint compound you may be able to find smaller size offerings at a lesser price.

Worth it? Needed? All depends on your budget (one car garage should take less material) and personal preference.If you own the residence / garage then I would work towards a finished slab that will hold up over time. If you are purchasing home/ garage - Congratulations!!!

Expansion Joint compound does have its advantages though in that you wont loose nuts ,. bolts, and screws in there AND you will be able to hose out the garage without water seeping into that outer perimeter joint.

Im a bit of a garage freak and used this material just so i could help hide the joints when I was top coating.

Lowes and Home Depot most likely will not have it. Search their websites for expansion joint compound before travelling over there.

[MAXELHOFF]

Pinche concreto.

How cold does it get where you live? How thick is the existing parking slab's concrete?

[DIIRTY-30]

Would this work for stress fractures in the slab as well? My garage floor split after an earthquake in '94. Live in socal so theres no worry about extreme cold. Any suggestions or tips on how to fill this? I occasionally find myself losing screws and nuts like George said too. Would be kinda cool to take care of it once and for all.


Heres a pic, kinda hard to tell but it runs from the front all the way to the back of the garage.

[herbivor]

You don't really need an expansion joint in small residential garages in normal climates. The slab won't expand. It only contracts after construction. Fill the gap with whatever you want, mortar will likely be the cheapest filler. Expansion joints are only beneficial in very cold climates where frost heave can cause differential movement, but even then all you only need a small gap, much smaller than what you have now.

[e30vert]

DIIRTY-30

Nope for that you need Roadware Concrete Mender. www.concretemender.com

As seen here

[george graves]

Sooooo......looked around at garage flooring. Even for a small garage - way too expensive.

These "race deck" type of tile systems is way over my budget. And it's going to be too much work to get an 50 year old, worn down, oil impregnated concrete floor read for epoxy...

Unless someone can talk me out of it, I think I'm going to get a left over roll of household vinyl flooring and glue it down....;)

[MAXELHOFF]

Blow out the crack and use caulk. wat?

You don't really need an expansion joint in small residential garages in normal climates. The slab won't expand. It only contracts after construction. Fill the gap with whatever you want, mortar will likely be the cheapest filler. Expansion joints are only beneficial in very cold climates where frost heave can cause differential movement, but even then all you only need a small gap, much smaller than what you have now.

Get 5 gallons of good paint and some muriatic acid to prepare the concrete. Paint it once a year, it's great! so clean

[Smelser]

socal? never mind. I was gonna say becarefull of frost and make sure if you fill it. to have air in the concrete unless you heat the shop 24/7.

[whysimon]

EVERYTHING expands and contrasts. The cheapest thing to do is; install backer rod and urethane sealant. do a quick search for your local division #7 distribution store and ask for sonneborn NP2, Tremco 240, Pecora Dynatrol II, or anything of the like. A 1.5gl pail will give you 77' at .5" x .5" joint. The pail is roughly $38-45 depending on where you live. You could also ask for a self leveling urethane.

[M-technik-3]

Get 5 gallons of good paint and some muriatic acid to prepare the concrete. Paint it once a year, it's great! so clean

Basically what I did 4 years ago. Go to the chinese emporium aka harbor freight and get some rubber mats for your standing areas.

[jrobie79]

just poured the slab and walls for my new garage...no expansion joint whatsoever. its not necessary