Question on filling gap between driveway and garage


Old 10-16-12, 08:17 PM
Thread Starter
Join Date: Oct 2012
Location: USA
Posts: 10
Question on filling gap between driveway and garage

Hello, first time home owner who has been getting into the diy work. We just recently had our driveway mud-jacked. It has improved the gap in terms of height; however, there is quite an opening in between the concrete slab and the garage. I want to know from those who have dealt with something similar what is the best approach? My concern is water getting down there and causing issues that could lead to the concrete slab sinking again.

I have thought of dropping some pea gravel down there to help with the water absorption or sand for that matter? I also am curious to is there a special caulk or filler I can buy to make this easy? I live in the midwest in IL, so we'll see freezing temps to the heat extremes.

To note from thje pic, the previous owner had some of that black stuff (tar?) in that area; but, since it has crumbled.

Also, there are small pot holes in the driveway as can be seen in the pic, if anyone has any ideas on how to fill those as well, that would be useful.

Thanks in advance!
Attached Images  
Sponsored Links
Old 10-17-12, 02:48 PM
Temporarily Suspended
Join Date: Jul 2008
Location: NY
Posts: 10,986
There is some caulking available at a local hardware store or Home Depot. I wouldn't pour cement in the gap but you can use cement in the other holes, depending on the size.
Old 10-17-12, 03:03 PM
XSleeper's Avatar
Group Moderator
Join Date: Dec 2004
Location: USA
Posts: 22,540
Likes Received: 104
As mentioned, they make a sealant for this. Look for PL Polyurethane S20 Self Levelling sealant. (Concrete or Grey). Clean the gap out so that its clean, then pour some clean silica sand (you can buy bags of this where bag cement is sold) into the joint until you are about 3/8" from the top. Take a thin board (such as 1/2" plywood scrap) and tamp the sand down. You want the self levelling sealant to be no more than 3/8" thick.

Block the ends by driving a stake tightly onto each end. If there are any cracks or dips anywhere in between you will want to block these with sand because the sealant will run out of the crack and make a giant mess.

Apply just a little at first... maybe filling it halfway, then when you get to the end come back and fill it the rest of the way. The joint will look better if you fill it slowly and let it flow out before adding more, and don't get it too full.

Once you're done, sprinkle more sand over the top so that no one steps in it and tracks it into the house. If you're worried about driving over it, lay a couple boards down to protect it. It will be sticky for a week or so.
Old 10-17-12, 03:05 PM
Gunguy45's Avatar
Super Moderator
Join Date: Dec 2007
Location: USA
Posts: 21,105
They make specific stuff for this though I'm not sure you will find the best product at a HD or hardware store. A specialty supplier might be better.

From what I remember the experts advising, you need to clean the gap of all debris. If it's quite deep due to all the movement it might be best to fill to an inch or so below the surface with pea gravel or stone chips, then insert an appropriate size backer rod, the apply the sealant.

I'm no expert but they will be along and give more specific info. I wouldn't rush to do anything til you hear from a Pro.
Old 10-17-12, 03:35 PM
chandler's Avatar
Banned. Rule And/Or Policy Violation
Join Date: Dec 2005
Location: USA
Posts: 39,967
Likes Received: 1
Vic, Brant beat you to it while you were "speed" typing . I have also heard of using butyl rubber in caulk form to fill concrete cracks like this. I do believe the pourable sealant made for it may work better, though.
Old 10-18-12, 10:01 AM
Join Date: Jan 2012
Location: USA
Posts: 147
If you feel more comfortable with a caulk gun in lieu of the pourable sealant you could use Sonneborn NP1 sealant. It is a polyurethane sealant that should serve your purpose. I would still fill the gap with sand but you do want to be carful to not over tamp the sand. This joint still wants to be able to allow for some movement.
Old 10-23-12, 07:12 PM
BridgeMan45's Avatar
Join Date: Oct 2011
Location: USA
Posts: 3,196
You may want to leave the top of the sealant about 1/4" below the level of the surrounding concrete, especially if placing it during moderately-cool temperatures. If you place it flush with the surface now, come next summer when the gap closes up as your driveway slab expands, it will squeeze the sealant you installed up and out of the opening, making it easy to tear out and off with wheel traffic going over it.
Old 04-10-14, 06:51 AM
Thread Starter
Join Date: Oct 2012
Location: USA
Posts: 10

Thank you guys very much for the sound advice, especially XSleeper. I proceeded with the project 1.5 years ago using the guidance here and it's still holding up great. Attached is a pic showing the PL Polyurethane S20 (great product!) still holding up, even with spring leaves and a bunch of rain overflow last year in the center for when the gutter can't handle the heavy rains it's still held up well without cracks

Some tips for others doing this after my experience:

1.) Buy an extra bag of sand! I barely, just barely had enough sand, a 2 car wide driveway for this small gap ate up an entire 50lb bag of sand, I hate running out to pick up stuff during a project and never did I think this much sand would be needed.

2.) I used garden stakes to secure the edges, make sure they are really flush against the sides of the driveway, I had a little overflow, not too bad; but, had a little more time in setup would have avoided clean up time later.

3.) Tamping down the sand is extremely important, in many areas this got into more crevices and cracks. Go slowly and let the sand flow down into the crevices.

4.) Buy the large caulk versions of the PL S20, more economical, I went through about 5 tubes of the regular stuff (my local store did not have it in stock, had I planned out better I would have waited; but, I needed to get it done before the cold weather hit).

I did the vertical section last fall as well to prevent water from getting in and it's still holding too, it's visible in the pic as well.

Name:  pic.jpg
Views: 40284
Size:  47.4 KB
Old 04-10-14, 04:17 PM
XSleeper's Avatar
Group Moderator
Join Date: Dec 2004
Location: USA
Posts: 22,540
Likes Received: 104
Glad its lasting. If you ever see any edges that are letting go, take time to do a little maintenance... cutting back the sealant with a utility knife and putting some new in. It will make it last a lot longer if you do. Thanks for the feedback.

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off

Thread Tools
Search this Thread
Display Modes