Have you spent any time walking through old cemeteries? If so, you know the effects the elements can have on headstones. Damage from surrounding flora and fauna, contaminants in the atmosphere, animals, and people can cause the stones to become unreadable over time.
Jump ahead to these sections:
- Step 1: Obtain Permission
- Step 2: Make Sure the Stone is Secure
- Step 3: Check the Outdoor Temperature
- Step 4: Look for Plants Stuck to the Stone
- Step 5: Inspect the Stone
- Step 6: Wet the Stone with Water
- Step 7: Gently Scrub the Stone
- Step 8: Rinse the Stone
- Special Considerations for Each Gravestone Type
- What Not to Use When Cleaning Gravestones
Want to preserve your great-grandparents’ legacy or fix a community treasure? Kudos to you for researching this subject before you gather your household cleaners and other materials — which, as we’ll cover, can often do more harm than good.
Know this for sure — it’s not going to be anywhere near the cost of a funeral to fix one. Here are some basic steps and special instructions for each type of stone.
Please note that these are basic instructions, and each stone should be individually evaluated. Treat aged stones delicately. Cleaning them requires the skill of an expert who has been appropriately trained by a conservationist.
You might be most interested in learning how to clean the gravestone of your loved ones or ancestors. You only have to ask the permission of your other family members to clean these headstones if this is the case.
On the other hand, are you interested in cleaning stones for historical or altruistic reasons? Make sure you get permission from the deceased’s descendants. They may be impossible to locate, so in that case, obtain approval from the cemetery superintendent or the municipal employee who oversees the cemetery. Know ahead of time that these individuals may not feel comfortable with an untrained person cleaning the stone.
Old gravestone bases may be unstable after hundreds of years. Make sure the marker you’re working with is secure and isn’t going to fall. Remember — you want to remain safe throughout the process.
Touch the surface of the gravestone with your bare hand. Is the stone hot to the touch? If so, do not clean it with cold water. This could cause cracks.
Consider covering the stone until the temperature lowers. You could use warm water to clean it if this isn't an option.
Also, don’t attempt to clean a stone when there’s any chance of freezing temperatures in the forecast. Water expands when it freezes, so the water could get inside the minuscule cracks in the stone and grow.
Your natural instinct might be to pull any plants off a stone as soon as you see one — but expert stone cleaners caution against this practice.
Instead, cut the plants, particularly ivy, at the root and periodically along the vine. Some plants’ suckers can damage stones. You can remove the suckers but it’s best to wait until the plant is dead to complete the cleaning.
Stop and scrutinize the stone before you begin the cleaning process. There may be indicators that you need to call in a stone preservationist to handle the job of cleaning the monument. Here are some things to look for on the stone:
- Delamination: Some stones are layered. Do not begin the cleaning process if you see that the stone’s layers are starting to separate. This is a job for a professional.
- Hollow sounds: Do you hear a hollow sound when you tap lightly on the stone? If so, don’t attempt to clean it.
- Large cracks: Whether the stone is cracked from an intrusive tree root or another source, do not attempt to clean the stone. The fragile stone may chip easily and should be repaired before cleaning begins.
First, it’s worth noting that you should never use a power washer to clean a headstone. This would do irreparable damage. Instead, use a pump sprayer set on a mist setting.
Gently wet the stone with clean water and watch as it dries. Look for stress cracks on the stone. If there are many cracks or they seem unusually wide, don’t continue the cleaning process.
Have you determined that the stone is in good enough shape to be cleaned by an amateur? If so, you can move on to the next step. Soak the stone and wait for a few minutes. Scrape the moss and other plant growth off of the stone with a wooden or plastic scraper.
Rinse the gravestone of any debris that you brought to the surface from your gentle scrubbing. You will notice that there was no mention of any cleaning products in this article. Most sources recommend not using any cleaning products until you have received training on which products will not harm the stone or the surrounding vegetation.
These instructions can be used to clean most gravestones but there may be special instructions to consider for specific materials.
Granite can become very hot in the summer and cleaning it on a hot day may be problematic. It’ll be difficult to keep the surface wet when water evaporates so quickly. The monument could end up looking streaky.
Marble is especially susceptible to damage when you use cleaning agents. Take care when cleaning a marble surface. Do not use wire brushes or aggressive scrubbing methods.
Bronze is different than cleaning granite, slate, or other natural stone. You can use the same steps when you clean a bronze monument — just add an extra step at the end.
Some experts recommend adding a protective coating to a newly-cleaned bronze monument. Some websites recommend adding a thin layer of wax paste. Buff the surface to a smooth finish once the surface dries.
Avoid vinegar solutions when you clean slate gravestones. The method listed in the steps above is appropriate when working with this natural stone.
Sandstone is soft enough to carve and hard enough to last for centuries. The problem with using sandstone is that delamination often occurs and it crumbles when moisture gets into the layers.
Be very careful when you work with sandstone headstones.
Professionals in the past used the following products and tools to clean monuments. Unfortunately, experts today agree that you should never use these products to conserve gravestones.
People have cleaned gravestones with bleach for years. In fact, you can still find some websites that recommend using this household product to clean marble and other stones. This is a mistake — bleach leaves salt deposits on headstones, which can break down stones’ surfaces and cause them to crumble.
Avoid using wire brushes. A wire brush will remove any algae that covers a stone but it will also remove parts of the stone as well.
Do not use power washers to clean gravestones. Power washers will remove contaminants from the surface of stones but will damage headstones in the process.
Finally, avoid using any power tools to clean a gravestone. Some companies use nylon wheels attached to a drill to clean the surfaces of stones. This does irreparable damage and can render stones unreadable.
Most people have good intentions when they clean a gravestone. Just make sure your good intentions don’t cause more harm than good. Follow the best practices when you clean your loved one’s stone.
Are you interested in preserving gravestones in your local community? If so, look for preservation groups that work in your area. Some groups host classes to teach others how to properly clean old monuments.