How To Repair Grout On Flagstone Patio

Devin Devine, stone masonry contractor based out of Blakeslee Pennsylvania. Projects completed across the U.s.a.
devin@devineescapes.com

I took some photos during a contempo flagstone repair task, and thought I'd put together a tutorial on how to repair flagstone, function of my continuing DIY flagstone series. Please note, that if yous need individual help with your flagstone project, I now offer DIY telephone consultation services.

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Flagstone patio prepare in cement. The patio, In Ambler Pennsylvania, has a few years on it and now most of the mortar in between the stones is all croaky upwards. In fact, there were no sections of unbroken mortar that were longer than 10 inches. As such, my prescription was consummate removal of all mortar from between the flagstones and replacement with new, blazon South masonry mortar.

How to Re-point Flagstone

Then the showtime thing to do is remove the old mortar. The mode you do that volition depend on the project. How big are the joints, how broken upwards are they, are they regular straight lines, or is the flagstone irregular and natural shaped? Either way, the tool kit that I utilize will by and large exist the same: an angle grinder with a 4 and a one-half inch diamond blade on it and a hammer and chisel, maybe a large flat head screw driver.

Another earlier photo. Close upwards: yeah, that cement is all broken upward alright

One manner to remove the one-time croaky up mortar is to have your angle grinder and cut a line through the center of the mortar….merely every bit deep every bit the cement joint. You do not need to cutting all the fashion downward into the concrete. An inch deep will do information technology.

like and then

After that y'all can accept a chisel and hold it at a forty v degree angle, and come at the joint from the sides. Strike down upon the mortar from the right side and then from the left. Should pop out fairly hands. Again, the method you lot use will greatly be determined by the shape and size and condition of your mortar joint.

and here the mortar is completely removed

This was an 800 square human foot patio. We used different technique on dissimilar sections, simply the above method worked for most of it. Some areas, the mortar had enough cracks in information technology and was loose enough that we could simply wedge a small-scale chisel–or a large flat-caput screwdriver–and just pry out the loose mortar.

Actually, most of the joints could have been removed with just a hammer and chisel.  And that sounds attractive, correct? Less noise, less dust, more eco. However.A) that would have taken awhile longer and B) many stones would accept popped loose that way. Using the hammer and chisel creates greater impact. Now if we bosom upward the stones and take to re-lay them…that's more work, more than cement, less eco. So we'll ordinarily effort using just the chisel–when also many stone pop up loose, we switch to the grinder.

Delight NOTE: there are other methods, and other tools that can exist used to remove the old mortar, this is simply one method, and not appropriate for all flagstone patio repair jobs. Anyway, repointing a patio is a lot of piece of work, so permit'south just go along going then.

Okay, so you've removed all the old broken upwards mortar from between your flagstones. Good task!

Have a sandwich, yous deserve it.

But before we get to learning how-to repoint our flagstone patio, you demand to clean out them joints, remove whatever loose mortar that might exist remaining and clean out the dust. My usual method is alternating turns with the leaf blower and the hose. Use a broom to pick upward any larger bits of old mortar that is withal on the patio. Blow out all the dust, so spray it down, then blow it out again. Your mortar will not adhere to grit, so whatever method you lot use, merely be sure to get them joints clean.

Replacing the flagstone joints with new mortar

Okay, and so you've removed all the old mortar and gotten them joints nice and clean. Now it's time to learn how to repoint a flagstone patio. ***Hither'south my method:

Get-go thing I practice is load upwardly my diamond trowel in my left hand and hold it over the flagstone joint.

So I take my tuck pointing trowel and slide the mortar off of my diamond trow…

And button the mortar downward in-between the flagstones.

Really push it downwardly.

Then add more if you demand to.

Use the tuck pointing trow to go the cement nice and smooth.

And look at that–you've just filled in-between you flagstone with new cement! I e'er believed in you.

Essential tools needed:

• grabo, the hot new vacuum lifter that makes lifting flagstones a bit easier. My review tin can exist plant HERE.
• expressionless blow type mallet. Many types to choose from….lately I mostly use my rawhide mallet, just the safe headed modernistic manner .deadblow is in my tool bucket too, and I'll utilize whichever is closer on mitt.
• brick hammer, for cut flagstone.
• Bending grinder. Aforementioned ane I apply. Keep this on hand for cuts that the hammer won't successfully make, or that will accept as well long with the hammer
• Diamond blades.
• Brick chisel.
• Knee pads–admittedly essential.
• diamond trowel
• tuck pointing trowel

A note well-nigh the mortar.***

I like to employ a fairly dry mix of mortar for this blazon of work. Masons call this a "stiff" mix, or a "tight" mix. I go just a tiny bit wetter than crumbly…well, maybe a little bit crumbly. This makes less of a mess, than wet mortar will. Also, since the cement is fairly dry, I can really push it down into them cracks. With a wetter mortar, if you push it down hard, or even but go to polish information technology out besides much, you'll push the moisture upward to the surface–which will crusade problems, such equally spalling and slap-up, later.  Drier stuff is easier to make clean and volition be stronger. Years down the road, this patio will still exist in good status.

But despite the squeamish dry mortar that I used, there's still a flake of mess to clean up. Ideally, I'll do a quick clean right and so and there, while the mortar is fresh.

***I demand to get back and edit this post with photos and description of my current method. First I need new photos! Anyway, I've discussed re-pointing flagstone and other paving with other masonry contractors…I partially wrote this article in order to nowadays my method, self taught, to other masons and see what they had to offer. Since then, I've modified my technique. I've been experimenting with using much more than dry out mortar. This cuts style down on the make clean-up time. Use really really dry out mortar. Just add enough water that the mortar all looks darkened, only is not actually damp. Pile information technology upwardly around the joints, one foot or so at a time…..work information technology into the joints with your tuck arrow…printing it in really good…..my old way, the way outlined above works fine–but I believe the really dry method provides just as much strength and durability and much less make clean-upwardly.

UPDATE: my new method of re-pointing flagstone is described here. Basically information technology's the same as earlier, simply with a much more dry mortar mix, firmer pressing-down with the narrow trowel, and much less extensive cleaning afterwardsc

Other methods that I have encountered have varying degrees of ease–but do not provide much immovability. I do Non approve of any methods that use a) too much water, or b) is not compacted enough, pushed down into the joint actually well. The mortar, whether you are using the super dry method or and other dry out method, must not be plastic. It can be bone dry, crumbly, or slightly damp…just it must exist more dry than a block laying mix. The cement you utilize to lay a cinderblock is only style too wet for course level application.

Some other super dry out method involves only sweeping the mortar into your joints. I know guys who fit their dimensional ((pattern-cutting)) as tight equally possible, with 8th inch or less gaps–and so they sweep dry out mortar mix into the joints and and so lightly mist it. Later on on pressure washing whatever brume. This method is easy….but since the mortar never gets pushed down into their, never gets properly compacted…I'm just not feeling it. Not my style. Will crack up.

Sponge technique is of import!

(okay, so this photo was taken afterwards, non when the joint was fresh, only y'all get the idea)

Have your grout sponge and dip it in water–then squeeze it out real well, yous want a rather dry sponge for this. Take one corner of the sponge and wipe downwards the one side of the flagstone mortar joint.

Then, employ a different corner of the sponge and clean the other side of the articulation. Okay, now yous're good. motility on to other work.

When the mortar has go thumbprint dry you can return and sponge it off once again.

And then exercise some other work for awhile and return to the newly filled flagstone joint a couple hours afterward, or nevertheless long it takes, until when the joint has become "thumbprint dry". Heat and humidity and how loose or tight your mortar mix was volition determine how long this takes….on a perfect 70 degree day, y'all may be able to work all forenoon, filling the joints with mortar, and then later on lunch you can go dorsum amd sponge off the joints a second time. This is considering your first pass with the sponge, when the joints were fresh, got up the bulk of the spilled mortar. To try and get it 100 pct clean when the mortar is fresh…will brand a mess.

And so sponge it off once again…see them footling white spots on the left side of the mortar joint? That's what we want to clean off.

Hit both sides…..again, always using a clean corner of the sponge! Use the same corner twice and you lot will exit a mortar haze.

Use 1 corner, and then the next. I really mean it. Always use a clean corner, or side, of the sponge.You lot can purchase grout sponges similar this, here.

Fifty-fifty when your bucket is full of dirty looking h2o, that's no problem–only dip squeeze that sponge dry out and and so use it, i corner at a time!

And then, I like to actually sponge off the mortar joint itself. This will shine downward any trow marks and leave you with a much more than consistent looking mortar joint.

Sponging downwards the joint itself (when it is thumbprint hard) will also make full small-scale gaps that you may leave behind with the trow. Look, I'grand pretty proficient with a trow–but still, piffling tiny spots can go left, little voids, nigh one quarter the size of a lucifer caput…little spots, ordinarily along the edge of the stone, not in the middle of the joint. These are spots where water tin can infiltrate, and cause a mortar joint to fail, sometimes within merely a few years. Worse all the same, that h2o could even get underneath your flagstones, cause thing to popular upwardly and come loose.

I'm not really certain how many masons use a sponge technique similar I exercise. What I practise know however is that when I come in to repair these jobs, I e'er discover fiddling tiny gaps in the mortar–little tiny gaps similar the ones that I myself sometimes exit behind with my trow–but that I ever correct, with the sponge.

***once more, the sponge is used a flake less, if y'all go with a super-dry out method.

The following photo is of the same patio, In Ambler Pennsylvania, every bit the ane I showed y'all fashion up at the first of the article.

Tada! A once weathered and deteriorating flagstone patio, like new.

Thanks for taking the time to read this commodity on how to repoint flagstone patios. Now go forth into the world and repair some former flagstone patios, similar a pro, like a real rock mason. Like Devin Devine.

Thank You

Delight note, that if yous need individual aid with your flagstone projection, I at present offer DIY phone consultation services.

DIY Hardscape Assistance

Telephone Call Rates:

$lxxx.00 for a one-half hour consultation.

$115.00 for a full hour.

These consultations tin also be conducted via email.

Monies are payable via paypal.

Related articles, DIY and hardscape how-to:

• • how to build a dry rock wall
  • how to build a flagstone patio
  • pre-winter one thousand maintenance
  • how to build a natural stone birdbath
  • what to use for under flagstones, concrete, sand, gravel, or what?
  • should you seal your stone patio?

Also, check out my sculptural forms in blue stone and slate:

Rock Sphere, private committee, Lehigh Canton Pennsylvania

Source: https://www.devineescapes.com/replacing-the-cement-between-flagstones/

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