There's Always a Bigger Hammer - The Paving Stone Demolition Experiment
'm trying to remove the cemented-in mystery stone from our pool deck. The same stuff is on our patio, so if I'm successful, I may go after that area too. Why would I do that? Cause it's ugly, bad stuff.
You can read about this delightful stone in my last post about our upcoming swimming pool renovation if you like, or you can stay here for the hard-core, hammer-slammin' action.
To update progress on the renovation, I've had two pool contractors give renovation options and quotes for a total pool re-do / repair. The first contractor thought we could remove the mystery stone from the original deck, and cover it with brick pavers. The second promoted jack-hammering the deck down to dirt and starting from scratch, with a new acrylic coated concrete cool-deck.
We're considering both approaches, but the paver idea hinges on successfully removing the stone, and they want $2,000 to do that.
Just to remove the stone, not to buy or install the pavers. Holy crap!
I decided to see if I could do it myself. I didn't think I had the proper tools for this operation, but a test run with what I had, could determine if it could be done at all. Of course, this job was too big for Sweetness, my trusty electrician's hammer, so I upgraded to a mini sledge and a mason's chisel. I'd used the duo years ago, to split bricks for a mailbox project. I figured they should at least get me started with the necessary destructive experiment.
Mini-Sledge and a Mason's Chisel
It was easy enough to chip the concrete off the edges of the original deck slab, but it was seriously tough going to get the stones to release. I had to chip along as much of the edge as I could, before driving the chisel under the stone. Finally, I'd give it a few solid whacks to break it free.
After a while, I got a small area cleared. A few stones were up, broken to bits, but there was some concrete bedding left behind. It probably wasn't the best hammer and chisel combination to be using, but it proved that the stone could be removed. It would only take a "short" 3 years of solid evening and weekend work to plink my way through all of it.
I chose to move up a level in hammer options. Tucked in my arsenal of hand-held concussive forces is Mjölnir, my mightiest hammer option. It is truly a hammer worthy of a Norse God, and it came to my possession through a character of mythological proportions, and I can't believe it's not been featured on this blog yet.
Mjölnir, next to a mere mortal's hammer.
Mjölnir is actually a weathered, full-size sledge hammer with its handle sawn off for one-handed use. It was given to me years ago in my brief tenure as a construction worker, by Joseph, a foul-tempered Lebanese construction electrician, with muscled, fur-covered forearms the size of gallon paint cans. He was an intense, scary dude, physically incapable of rendering a single sentence without at least four curse words. In fact, sometimes his sentences were artistically woven entirely from curse words. For some reason, he liked me and let me keep this bastardized sledge. I think he wanted to craft a larger one for his own use. I don't know why; he could slam an eight foot grounding rod all the way into the ground as fast as you or I could push a thumbtack into a bulletin board.
Just like the God of Thunder, eh?
Mjölnir does its job. It hit with a tremendous impact, driving the chisel under the stone with only a few swings. It was horribly unwieldy though. Swinging a full-size sledge with one hand is a little more intense than swinging a tack hammer. I even managed to treat myself to a ricochet shot that slammed the mighty hammer into my foot, nearly knocking me over. It didn't hurt a bit at all though. It didn't hurt because I am one tough DIY'ing action hero of a man,... who just happened to be wearing steel-toe boots.
Steel-shod toes are happy toes.
I proved it was possible to remove the stone with a chisel and hammer, even a big damn hammer, but it was slow going and tough work. It physically wore me out. I thought perhaps I needed a better chisel, so I called it a day.
I had muscle aches on top of muscle aches the next morning. I'm out of shape for sure, but swinging an overweight hand-sledge in a crouched over position for hours and hours, days and days was going to be miserable. I clearly needed a better setup. Luckily, I'd won a Home Depot gift certificate at work and it was positively straining to free itself from my wallet. I headed over to my friendly neighborhood, big orange box store to check out the tools,... and visit Bad Dogs in the parking lot, of course.
Naturally, I came home with a new power tool. Enter a big hammer drill, featuring 2.1 foot pounds of impact, 4,500 beats per minute. That's a pinch better than I can do by a hand. This bad boy is a beefy Makita HR2621 1" Rotary Hammer, with anti-vibration technology. A new self-sharpening SDS plus chisel bit came home with it.
An example of a well chiseled physique.
Unlike my 1/2 inch cordless hammer drill, this roto-hammer has a third setting:
- Drill Only - spinning for standard drilling through wood, etc.
- Hammer Drill - spinning, plus impacts, for drilling through masonry
- Hammer Only - the chuck does not spin at all, for chipping /digging, etc.
For this adventure, it was hammer only mode, the setting my cordless hammer-drill does not have.
Stop. It's Hammer Time.
Ohhh, hell yeah. This thing rippped up the "mortar bed" (?) of concrete the stones had set in much faster than the ol' hammer, chisel, and brute force I had been using. Unfortunately, it still took forever to pop the full size stones off, but it did it with a lot less effort. My visions or ripping through like a bulldozer, sadly, did not come close to reality. It was still slow going.
I switched to a stance I've learned from every single movie and TV show I have ever seen set in the streets of New York City, "jack hammering construction worker." I believe all aspiring, male actors in the city get their start in this role, well either that or "construction guy eating a sandwich, next to jack-hammering construction worker."
Either way, it was fun. It did make it easy to chip a few inches from the edge, fairly quickly.Still slow going, but again, less effort than swinging an oversize hand sledge. I even began thinking about a sandwich myself (I could totally nail that acting thing).
A friend at work had given me another idea to try. He'd thought that I should use a masonry blade in a circular saw to slice the top layer into pieces that would be easier to pop off. Maybe that would help. Of course, I didn't have a masonry blade on hand for the circular saw. I did, however, have a diamond blade mounted in my Cordless Cutoff Tool
It slices! It dices! It can even cut a tomato!
I did a decent sized section, but it really chewed through my batteries in the process. I guess the cheap blade and the heavy resistance of cutting a 3/4" thick stone and concrete really put a draw on the power. I emptied all three batteries. I had one on the charger as I tried whacking again with the big sledge and chisel, thinking I could simply pop the squares I had cut out. It was a little better.
That quickly led me to try sitting on the diving board breathing hard and drinking vitamin water, which worked nicely for me, but didn't accomplish any actual work.
Success at last!
The roto-hammer, made short work of it. I finally had the winning approach. The problem was, I couldn't charge batteries in the cut off tool fast enough to keep up with the cuts I needed. I'd need also to make more cuts to get the pieces to the best size.
In the end, it wouldn't be a problem, because fate had taken me by the hand and led me to the solution. Let me take you back in time to my the shopping trip, when I was literally standing in the checkout line of Home Depot with this:
After a few moments, the lady at the Pro Checkout called me over to her station, with no waiting in her line. As I walked over, I saw this:
Waszzat? A grinder included?
A speedy check of online reviews later and I'd added the first two Makita tools to my arsenal. At the time, I didn't know I'd want a grinder for this project. Sure, I've wanted one for a while, but "free" really closed the deal for me.
I switched the blade over from the cordless, and let this bad dog run free. With an inexhaustible supply of electricity and a much higher RPM, it tore through stone, rendering it into flying dust.
"All we are is dust in the wind,..dude."
-Bill and Ted
This was an easy tool to use, especially considering the incredible amount of work it does without much muscle power. It cut stone and concrete with almost no effort. I really like the second handle to keep it under control and prevent it from tasting human flesh. Its going to be active on lots of future projects around here.
I cut a grid-like pattern on both sides of the diving board, taking care not to cut too deep and damage the slab below. In hind-site, I think I'd make a good dentist. This is pretty much what they do right?
I had finally, finally arrived at a good demolition solution. I'd cut the grid roughly into 6 inch squares. The roto-hammer slid right under the corners at a low angle. Within just few seconds, I could hear the sound change and the "tile" would pop up, usually in two pieces.
It was way easier than the sledge hammer approach. Still it was hot work. I really wanted to jump in that pool.
After a quick clean-up the deck was exposed. There was still a fair amount of mortar, but it could be cleaned up later if we decide to go this route. I figure I'd chip up the high spots with the roto-hammer and then get one of those cup grinding-wheels to clean up whatever was left. It can be done.
With the final process discovered, I think I can at least get the stone up in a couple weekends. But, for now, I'm going to stop, until we decide if we are going to resurface this with pavers or a coating or if we are going to have the entire deck demolished.
That I'm not going to do. Sure, I could get my hands on an electric jack-hammer and bust it up, but I don't have the expertise to avoid damaging any underlying structure that may need to stay intact. Plus, that is a lot of material to cart to the dump.
For now, I have this little heap. I'll smuggle a little out each week in the trash if I have to.