The portion of my driveway that could connects to the driveway that goes to the rear of the house has pulled away a bit.
I figure I want to keep water from going down there what sort of sealer should I use?

Backer rod and LOCTITE® PL® S20 POLYURETHANE SELF-LEVELING CONCRETE CRACK SEALANT. Stuff is super sticky. You will want to tape along the sides.

Sonneborn sonolastic paving joint sealant and backer rod. It is what is spec.ed for commercial work. I have seen it online. I need to do a bunch of joints soon myself. They sell a caulk gun like applicator which is needed also.

Not familiar with backer rod. Is this what I need?
http://m.homedepot.com/p/Sika-...Rod-108130/202523820

I think the joint is fine like it is, it is there for expansion. If you want to fill it I would use paver sand from home depot and just sweep it in there, it will allow for expansion etc. If you use some sort of synthetic sealant, you want it to be fairly pliable so the concrete can expand and contract with temperature change.

quote:

Originally posted by jimmy123x:
I think the joint is fine like it is, it is there for expansion. If you want to fill it I would use paver sand from home depot and just sweep it in there, it will allow for expansion etc. If you use some sort of synthetic sealant, you want it to be fairly pliable so the concrete can expand and contract with temperature change.

Around here, and when in Mn. for years it was not unheard for concrete paving to buckle at the expansion joint next to the bridge decking during the summer. The DOT says it is because the expansion joints fill with sand and road dirt over the winter, spring brains packmit down, and this inhibits proper expansion at the joint. Also occurs at expansion joints between concrete panels without a bridge deck involved. These failures are often dramatic blowpots when the temperatures rise during the summer. Products suggested previously, self leveling, and backer rod, are the typical products used.

quote:

Originally posted by Black92LX:
Not familiar with backer rod. Is this what I need?
http://m.homedepot.com/p/Sika-...Rod-108130/202523820

Correct (size is important)

quote:

Originally posted by Censored:

quote:

Originally posted by Black92LX:
Not familiar with backer rod. Is this what I need?
http://m.homedepot.com/p/Sika-...Rod-108130/202523820

Correct (size is important)

How should one measure for proper size?

quote:

Originally posted by Black92LX:

quote:

Originally posted by Censored:

quote:

Originally posted by Black92LX:
Not familiar with backer rod. Is this what I need?
http://m.homedepot.com/p/Sika-...Rod-108130/202523820

Correct (size is important)

How should one measure for proper size?

What is the largest and smallest opening?

I just did our driveway last summer. Cleaned all cracks with a pressure washer / broom / screw driver / putty knife first, let it dry, then used a dense foam to fill all the cracks to about 1/4" below the surface. Some types of foam / backer rod was very dense and round. What worked for me was a roll of 25' x 6" x 3/4" dense foam similar to backer rod but that let me easily cut pieces to size. Some cracks needed larger sizes than others.

Once the cracks were filled with the foam using an exacto knife and putty knife, remember to add barriers to the edges of the cracks so the caulk doesn't all drain away. After that, use vulkem, silex, or other self settling caulk. Make sure it'd dry before driving on it. Pick one type of caulk as their colors vary after they dry.

quote:

Originally posted by Black92LX:
Not familiar with backer rod. Is this what I need?
http://m.homedepot.com/p/Sika-...Rod-108130/202523820

Yes, you use that to fill in the bulk then apply the cauk in over the top with > THIS

quote:

Originally posted by Censored:

quote:

Originally posted by Black92LX:

quote:

Originally posted by Censored:

quote:

Originally posted by Black92LX:
Not familiar with backer rod. Is this what I need?
http://m.homedepot.com/p/Sika-...Rod-108130/202523820

Correct (size is important)

How should one measure for proper size?

What is the largest and smallest opening?

Largest crack is about 1/2" though the widest opening is 1"