need to replace expansion joint filler

Hello,

I need to replace the expansion joint filler where a sidewalk (about 2’ wide) goes between the garage and brick stairs and also wider area (about 6’) between the garage and the house. I believe what was there (which has mostly disintegrated) was a fiberboard/asphalt material. The joints average 3/4” wide by 4” deep and the longest run would be about 14’. I’m in New York City, so the weather varies widely in terms of temperature and humidity during the year.

Would it be best to replace with the same material or is there something better now?

If it is best to use the fiberboard, is there a particular caulk or sealant I can put on top to help prevent water seepage?

The joint widths average about 3/4” but vary from 1/2” to 1” in some areas. Is it better to overfill or underfill the gap if the board isn’t a snug fit?

Thanks in advance for any and all answers/advice.

ddr

 

http://forum.doityourself.com/showthread.php?t=278179&

 

Tscarborough,

Thanks for the link. I had actual read this thread but wasn't sure about a couple of things:

"If you ensure that the joint design is correct, you should be OK. It is not a matter of filling the joint with goo and hoping for the best.

The depth of the backer should be half the width of the joint, and if the joint widths vary by a significant amount it is worth getting the proper sized backer rod. The joint material MUST form an hour glass shape, so be sure and tool the joint as the material sets. It is also worth buying a primer and coating the edges of the joint. NP1 by Sonneborn is an excellent sealant; the ones carried by the big boxes in a quart bottle are junk."

As I mentioned, the open joint is about 3/4" wide and 4" deep. From what you said above, does that mean to just put the backer rod in about 3/8" below the surface, leaving the joint empty from the backer rod down, and then put the sealant over the backer rod? Won't that leave the joint fill in danger of caving in under weight (snow, ice, etc)?

Sorry if this is a dumb question; never worker with this stuff and want to try to get it right the first time.

Thanks.

 

No, for 3/4" joint, you would use 1" backer rod, and that combined with the sealant should be sufficent. If you like, you can remove the old expansion joint filler, and replace with sand to the level of the (bottom of the) backer rod.