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Redoing a Previously Sealed Surface!

If the surface has been sealed in the past, a different assumption takes over the process. That is, - this is not the same flooring as when first installed. However, you can successfully restore that floor.

If you will read this entire page you will save yourself time, money, and frustration. It is easy to redo another companies failed sealer, but we want you to understand the conditions and the logic of the process we discuss.

You are no longer considering sealing a "Mexican tile floor", a "brick" floor, a "flagstone" floor. It is now flooring that might contain a sealer which creates different absorption characteristics.

Stripping only removes sealer to the surface, not what is below the surface. Therefore, the stripped surface must be considered, potentially, - partially sealed. The job of a sealer is to "repel" things. This can include a new sealer. If the bond between sealers is not good, the result may be some degree of separation of the two sealers, i.e. peeling.

Here is an example showing that even though a stripped floor looks perfectly natural, that may not be the case. This is a red brick - "common" type.

A = Sealed     B = Raw (unsealed)
clean, protect, seal tile - stone - pavers - brick

A strong stripper applied to part of the sealed half.
clean, protect, seal tile - stone - pavers - brick

3 minutes later: wiped off and the sealer is removed.
The stripped side looks the same as the raw side.

clean, protect, seal tile - stone - pavers - brick

They are not the same!
Note the water drops do not absorb into the stripped half,
but immediately absorb into the raw side at arrow.

clean, protect, seal tile - stone - pavers - brick

Conclusion: Stripping will make the floor ready, but no stripper can reach a sealer below the surface. Therefore, you only need to understand the floor as it exists after stripping and choose the sealer accordingly.
After stripping, test the absorption range ........ Click here

Usually, problems are due to lack of information before starting the job. It really is a simple, satisfactory, and rewarding project with a little preparation.

Keep in mind:

The secondary goal is the appearance.
The primary goal is a problem free sealing job. This is the reverse of the way a project is usually addressed. However, the pretty appearance will not be so important if the job needs to be redone in a year or less. Remember, you have to move furniture again. You will see how to achieve the appearance goals in other ways than just the sealer.

Before deciding how to proceed - evaluate the following criteria:

Do You Really Need To Strip The Old Sealer?

If the existing sealer is not well bonded to the surfacing, there is little point to putting anything on top of it. It will continue to lose bond over time and wear and peel from the surfacing. A good way to evaluate the quality of the existing sealer bonding is:

If there are already areas of peeling, it is reasonable to assume there will be others and the bonding overall is risky.

Use a piece of tape to see if you can lift the sealer from the surface. You should not be able to do this "forced peeling" if there is a good bond.

The Old Sealer Has To Go, Now What?
Choose a stripper from our suggestion list here.

What if the surface had a color material applied before it was sealed? Will the stripping hurt the color?
It could!  Therefore, you want to test a small out of the way area first. If that does happen, here are the options:

If the old sealer is a water based coating type - test a wax stripper from the sealer preparation section here.

If the old sealer is a solvent base, you can drop many levels of aggressiveness of stripping by trying mineral spirits, then moving up to lacquer thinner

Choosing The New Sealer
Before stripping, identify the old sealer type per these tips so that you maintain compatibility as much as possible Click here

An option for tough situations where you really cannot figure out what was on the floor before!

When the known, or unknown, conditions have created a situation where sealer bonding is risky, we always suggest the use of a petroleum solvent based acrylic sealer. Sometimes you need to dilute it a bit per the manufacturer recommendations to lower the solids level to get good deep penetration and bonding.


The immediate beauty and ability to bead water are not very important. Patch test and allow ample time to evaluate the results. Re-seal projects are potentially so touchy that a test area should be evaluated after a month or more during which the flooring has been subjected to all future abuse including traffic wear, sun, heat, rain, sprinklers and maintenance procedures. Remember that a newly sealed surface always looks beautiful, but a marginal application of sealer under adverse conditions of weather, moisture, preexisting non-compatible sealer, etc. can be at high risk of future peeling. As with a new application, risk approaches zero if the correct sealer is selected and applied according to directions. Follow all directions and cautions on the package except as might be modified by the above information for redoing old sealers.

CAUTION: Regarding tile that has been sealed with oil and wax:

If the tile had been sealed with an oil (linseed oil, motor oil, etc) and wax technique that was popular years ago - you need to consider the following:

There are still companies that supply tile they call "sealed", but the technique is to use oil to saturate the pore structure of the tile and support a subsequently applied film of wax. This is quite attractive, but does not last. The wax requires a high level of maintenance and the technique does not impart any of the other benefits to the flooring as do modern sealers.

You do not want to reseal with a water based sealer as it will not properly penetrate and/or bond - very high risk!

Resealing with a solvent base sealer may re-liquify the old, dried out oil and cause patchy discoloration ( see below ).

Therefore, you may want to stay with the wax and put up with the high maintenance requirements. However, if that is not an acceptable answer, then there is another option for you to test and evaluate. It is to use a sealer that indicates "color enhancement". These have a natural tendency to darken the tile a few shades. This darkening will tend to mask patches of discoloration if they occur.