Pavers Over Concrete?

[Pelican]

I'm bidding a job where the homeowner wants a paver overlay on both the horizontal and vertical surfaces of his concrete stoop/steps. Unilock advises strongly against this procedure and voids their warranty on any pavers installed in this manner.

Trouble is, I've got competitors who routinely do this work and the jobs seem to last. I think I've seen work by some of the guys here that illustrates this. How is it done?

Keep in mind that I'm in the northeast where we experience multiple freeze/thaw cycles per season plus this stoop has full exposure to the elements, no roof over it. My fear is water getting between the pavers and concrete, then lifting the pavers from the frost.

Any suggestions?

[Bill Schwab]

Pelican:

Who is you rep at Unilock? Is it Len Browning? He used to work at UNILOCK Chicago then relocated to NY...Is Lyle Selk still the GM there? He too was in Chicago.......And, with that, unilock had best get it's signals straight...We were authorized contractors in chicago before moving west...We routinely bonded pavers to front stopps, in the manor you mentioned...OUR SALES REPS recommended this, the engineers told us this was OK, and we did it....You mayb have better results using latex concrete (Laticrete) rather than using Unigoop, as every time we bonded a verticle surface, we would have to make forms to hold the brick and stake them against the sides otherwise they would slide down and set in wierd positions...

My questions would be to Unilock, 1) have they changed thier recommendations in the last 2 years, and 2) why is this process recommended in Chicago, when it is not in NY?

By the way, there were jobs we did 10 years ago, where pavers were laid directly on top cement...Not one flaw has happened...So, what is the beef?

Hope this gives you some insight to what need be done...

[Pelican]

Lyle is no longer at the Brewster plant, I haven't met the new manager yet. The new guy has really turn the place upside down, I can't say it's been an improvement. My rep now is Michelle Duarte, she's been there as long as I've been doing this work. I don't know Len, but he may be at Brewster. They're in the process of building another plant in Goshen, NY, he may be there.

It's curious how the Chicago a New York plants have different recommendations. I've been using Liquid Nails construction adhesive with good results for my work. About 1/3 the cost of the Unilock glue and same performance.

Are you saying you glue each paver in place? You mention latex concrete, is this glue or actually concrete? You don't have problems with frost popping the bricks?

[Bill Schwab]

Pelican:
First, you want to lay the verticles. What we did was took the extra brick you would use on the horizontals and used it to brace the verticles until the next day. Most of the time, you can jam them into the verts and they will stay. When they get stubborn, use concrete type forms and stakes. Let the goop set, then come back and lay the horizontals.
On the horizontal concrete, you lay pavers from the toe of the landing in to the house. Make your cuts at the threshold. Bond only the outer edge bricks and use only a few squirts, so the goop will form small pockets under the stone so water can drain out. The center you just use sand like on top of gravel. Let is set, keep traffic off for a day, then turn over the job.

As far as Laticrete goes, you first have to seal the stoop with approved mix. Packeaged Concrete corporation has this product, kind of a milky white stuff, just read the directions and you will be fine. Then mix the laticrete,trowel it on and set the brick...

I personally like to set the edge stone just a tad over the verticles so it looks like a bull nosed effect. Occasionally, you may have a stone come loose, so go back bond it down and you rarely ever hear from a client. We have even set these over steel stairs and they are still there....

I am saddened to hear Lyle is no longer at Brewster....He was a great guy, deeply missed when he left Chicago, but Scott is good there and we all liked him as well....I wish Unilock would get out here, we have a great supplier now RCP block and Brick, who makes Keystone, but, I sure miss my Unilock!

[Will Pacala]

Is there any reason you can't tea r up the old sidewalk and start with a new base and build up? That would be easier, and you shouldn't have any up-front trouble or call-backs.

[Paul]

It's done all the time here. Follow Bill's advice and it will go down quick. We use epoxy on the edges in high traffic areas, it isn't affected by freeze thaw as much as Paver bond or other softer glues.

[Stonehenge]

Will, you could tear down and rebuild from scratch, but there's no way that way would be either easier or faster.

Pelican, I think that over time companies look to find ways to block off paths leading to financial liability. The more exclusions, the easier it is to defend. Each year my contract with clients gets a little longer, adding a new blurb to better protect me. I'm not saying they are doing right or wrong, just giving MHO about what I think is happening.

And when it comes to this kind of install, we don't have a call to do it very often, but when we do, we'll either glue it, or now that we have a mason on board that has taught us a great deal, we'll mortar it.

[Will Pacala]

I just thought that the quality of work would look better when it's done the real way. But if you say that it's been used before and with no problems than try it and tell me how it worked.

[Bill Schwab]

Will:

So long as the concrete stoop or flatwork you are bonding to is in good shape, all you need do is follow what I posted. If you arer bonding over a stoop that has been cracked up, you need to decide weather or not you can repair it, or you need to jack it out and rebuild it.

[Will Pacala]

Ok, Thanks for all the info. I'll keep that in mind but don't plan on doing any paver jobs in the middle of December.

Thanks

[Stonehenge]

It's funny you mention that - we had a client that as we were building an arbor, they were finishing up putting thin brick on their existing poured stoop. Nothing was plumb or level to begin with, and it was reflected in the thin brick. The worst part was, they went to grout the thin brick, and I'm not sure what they did, but when we came out the next day, the brick looked like they had been painted over in a thick grey paint. And they had a portable heater, with the area enclosed in tarps, evidently to dry it. It was very dry....

Looked to me like the grout 'painting' was the final blow to an already shoddy project...too bad they didn't call us for that....

[Rex Mann]

Out here overlays are very very common. We even did them in Northern Ohio. Bill's advice is on the mark. However, I also include in my contracts on overlays....

"...the paver overlay will mirror what the concrete does under the pavers. Therefore, there is no installation warranty on overlays..."

As for the vertical overlay...we sometimes make veneer out of the pavers and use those for the verticals but, that depends on the layout and situation. The veneers are much less weight to hold up while the adhesive sets up.

Peace,

Rex

[Will Pacala]

It's not too big around here although I've seen it done once or twice. Never is it done on a driveway.

[Bill Schwab]

There is something else I just thought of as well...There are certain paver companies that make what they call "splits." Simply put, these are brick pavers 3cm thick, with the intent that you will be mortaring them down. Rex had a great idea by cutting them in half, as the weight will be easier to work with on the verticles.

[Will Pacala]

Never heard of them. Do they have a website?

[Stonehenge]

You can get them from many of the same companies that make clay brick. In Wisconsin everyone calls them thin brick.