If you have ever lived in a home with vinyl siding, chances are very good you have seen the damage a flying rock can do. Vinyl siding is very durable and resistant to UV and water damage.

However, impacts from stones and baseballs tend to crack the siding, and will often do so much damage the siding must be replaced. In other situations, vinyl siding may not be physically damaged, but simply detached from the structure.

Today we will discuss the process of resolving these issues the way a professional craftsperson would approach the repair and offer a few “pro tips” to make the project easier to complete.

How Do I Get Started Repairing Vinyl Siding?

To make a repair to vinyl siding the first step is to decide which method to use. Vinyl siding can be repaired (or replaced) fairly easily, but the project can appear initially daunting. Since vinyl siding is designed to hide the nails or staples holding it to the structure, vinyl siding can seem confusing to remove.

Thankfully, in most cases, the siding can be repaired in place. However, in some cases the damaged vinyl siding must be replaced, so we will discuss the process of removal and replacement as well.

Repairing vinyl siding using repair kits is often the most practical solution for vinyl siding repair. However, these kits have disadvantages as well, so the installer should make an assessment of the issue before assuming a kit can solve the problem.

How Do I Know If I Can Use a Repair Kit?

The professionals working with vinyl siding every day will usually not attempt to repair a section of vinyl siding, but rather just replace the damaged section. This approach has both advantages and disadvantages depending on the situation, so here we will view a typical repair from the viewpoint of both a homeowner and a professional vinyl siding installer.

For this example, let’s say the home has horizontal lap siding (by far the most common) and was impacted by a rock thrown from a lawnmower. Most vinyl siding thicknesses range from about 35 millimeters to 60 millimeters.

The difference is important, as the thicker the vinyl, the more resistance it offers to impacts. In most cases, horizontal lap siding will be somewhere between 35 millimeters and 45 millimeters thick, where other profiles (such as those that replicate the look of cedar shakes) are usually closer to 50-60 millimeters thick.

Repair kits can usually be used regardless of the thickness of the vinyl, however aesthetically, larger repairs can appear unsightly. For this reason, most professionals will opt to replace a section of vinyl whose damage exceeds more than an inch or two. 

How Do I Know Which Vinyl Siding Repair Method To Use?

The most likely vinyl siding you will encounter is horizontal lap siding. The two most popular designs are shiplap and dutch lap, which will represent the vast majority of vinyl siding on homes today.

These profiles vary slightly, but both shed water very efficiently. Dutch lap siding is usually the easiest to repair using a kit because it offers a flatter shape than shiplap. To identify if you have either of these designs, the easiest way is to hold a flat object, like a level or straight board firmly against the siding.

If a considerable amount of light can be seen between the flat object and the wall, you probably have shiplap siding. Conversely, if very little light passes through, the siding is probably dutch lap. If you are still unsure, a smart move is to remove a piece of siding large enough to show the profile and take it with you to your local supplier. They will know which you have by looking at your sample.

Vinyl siding repair kits usually come in one of three versions. These include fiberglass, tape, and caulk. Other repair methods also exist, but most consumers opt for a version of these methods because they are simple and easy to install. Here we will discuss these methods and the tools often required to complete them.

One of the oldest and most used methods used to repair vinyl siding is fiberglass. Fiberglass is a mixture of fiberglass strands and resin, which when mixed with a hardener, becomes very hard and durable.

Fiberglass repair kits usually involve fiberglass cloth as well, which is embedded into the resin mixture and forms a surface even harder than the vinyl itself. This is one reason why most professionals will not attempt a fiberglass repair on a hole larger than a couple of inches. Vinyl siding is designed to remain flexible as it absorbs both heat and cold to prevent cracking and splitting of the panels.

Fiberglass also remains somewhat flexible, but not to the extent of the vinyl. Unfortunately, when the vinyl expands or contracts with the ambient air temperature, often the fiberglass does not. This can cause puckers in the siding panel as the vinyl tries to move around the repair. This is why smaller repairs are often more successful than larger repairs, as the puckering is minimal and less noticeable.

One disadvantage of using fiberglass repair kits is that in most cases, the fiberglass will not match the color of the siding. Fiberglass usually takes on the color of the hardener used, which is often white or red. The fiberglass itself is usually gray, so when the two are mixed, the result is often unsightly and must be painted.

This can be tricky, as vinyl siding is not only flexible, but the color will usually fade over time due to exposure to UV light from the sun. Therefore, matching the color can be a challenge. In addition, the fiberglass cannot simply be painted over as the material will require some amount of sanding after it dries.

To complicate matters, nearly all vinyl siding will have some form of texture, usually designed to replicate wood grain. This can be extremely difficult to match seamlessly, so these types of repairs are often made when the damage is not at eye level. Most of these fiberglass kits will follow the same installation procedure, but the directions provided by the manufacturer of the kit should always be closely followed. 

In this section, we will describe the typical processes used to make a fiberglass repair. This method will use more tools than a comparable repair using tape or caulk, but will also offer the most customization of the repair because it can be shaped after it dries.

Here are a few common tools employed while using a fiberglass repair kit, but others are available:

  • Pry Bar
  • Flat Bar
  • Siding Removal Tool (special tool for detaching one panel from another)
  • Hammer
  • Sharp Utility Knife
  • Scissors
  • Putty knife
  • Sandpaper
  • Ice cream stick or another disposable mixing paddle

Step 1. Loosen the Siding

This is done to gain access to the backside of the siding. Part of the process is to apply fiberglass cloth to the backside of the siding to facilitate adhesion to the vinyl. This is usually done by using the siding removal tool to disengage the panel from the section below it, however it is not typically required to completely remove the siding panel. 

Then, the small mixture of fiberglass is mixed using the fiberglass, hardener, and mixing stick. Fiberglass has a very short work time, which means the fiberglass begins to harden immediately after mixing. 

The work time is usually only about five minutes, so the fiberglass cloth should be cut and dry fitted to the repair before the fiberglass is mixed. Otherwise, the fiberglass will likely harden before it can be applied to the vinyl.

Step 2. Apply the Cloth

Once the small amount of fiberglass has been mixed, it is then applied to the cloth along its perimeter, which causes it to act as an adhesive. The cloth is then secured to the back of the siding, allowing the cloth to work as a backstop for the rest of the repair. It is important to smooth out the cloth, as wrinkles can protrude through the final repair resulting in a very rough appearance.

Step 3. Apply the Fiberglass

With most kits, the next step is to wait about thirty minutes to allow the cloth and fiberglass adhesive to stiffen, but not cure. This is designed to prevent a “cold joint”, meaning the fiberglass on the cloth is still chemically active and tends to bond well with additional fiberglass. The next step is to mix more fiberglass using the same technique as before, but mixing just enough to make the repair.

Adding additional fiberglass beyond the surface of the repair usually results in additional time and effort, as it must be eventually removed to avoid a visually unattractive repair. After this fiberglass has been allowed to cure completely (often 24 hours or more), it can be sanded and painted.

Step 4. Sand and Paint

After the fiberglass has completely cured, it is sanded, primed, and painted. Generally speaking, the more time spent smoothing and replicating the texture of the vinyl, the better.

After the fiberglass has been sanded, it can be primed using a high-quality exterior primer/paint, usually made just for painting vinyl. This primer/paint typically includes a polymer that allows it to not only adhere very well to vinyl but also remain flexible so as not to crack when the vinyl expands due to heat.

Professionals will often spray this paint, but since most DIYers do not have a paint sprayer, it can be done with a brush or roller. 

For do-it-yourselfers, this can prove to be the most difficult part of the repair. As mentioned previously, vinyl siding will fade in color over time as UV damage from the sun takes effect. This fading can make it very difficult to make a seamless repair, as even a new piece of the same siding will be noticeable because it will not be faded.

In these situations, most professionals will have special paint mixed as closely as possible to the existing siding color, even though it has faded. This is usually accomplished by computer scanning of the siding to determine the shade.

If the computer has done a good job in matching the color, a couple of coats should be sufficient for a permanent repair. If the color seems off, the paint can be remixed and applied again.

In recent years, other repair options have become available to help resolve the issues surrounding fiberglass repairs. One of these is repair tape kits. These kits employ transparent tape designed to adhere to vinyl and can be cut and shaped to match the damaged area. Tape is usually easier to install than other repair methods, as it can literally be installed in minutes.

Tape repair kits will often come with a vinyl siding cleaning solution to facilitate adhesion to the vinyl siding. This greatly increases the effectiveness of the repair and helps provide the best connection to the surface.

After the area has been prepped with the cleaning solution, the professionals will cover not just the hole, but will often extend the tape under the section above the repair. This recreates the shingle effect of the siding and helps ensure that the repair will be long-lasting.

Tape repair kits have the advantage of being both temporary or permanent, which allows homeowners to prevent additional damage when making a permanent repair is impractical. For example, some homes have an uncommon siding color that is not available locally.

In these cases, although replacing the siding may be the best solution, the siding must be specially ordered. Depending on the geographical location of the home, this can be very inconvenient as additional damage from inclement weather can occur while the homeowner waits for the new siding.

This situation is a perfect application for a tape repair, as it will prevent water from getting behind the siding via the hole, yet it can be removed later with common solvents. After the tape has been applied, it can be painted using the same techniques as when painting fiberglass.

Probably the easiest way to repair a hole in vinyl siding is to use a color-matched caulk. This approach can be very simple if the siding is a commonly available color, such as white. However, uncommon colors will usually result in special ordering color-matched caulk, which can be relatively expensive.

The most important consideration, however, should be the quality of the caulk.

Using silicone-based sealants, like kitchen or bath caulk is strongly discouraged to repair vinyl siding. There are two reasons for this. First, these types of sealants will usually degrade in sunlight, as they are designed for use only indoors. Secondly, silicone-based products are usually resistant to paint (unless they are designed to be painted) and tend to make the repair unsightly.

Therefore, when using color-matched caulk it is a good idea to purchase the best available.

Once the caulk has been obtained, the application is no different than any other caulk, although a thorough cleaning of the area to be repaired is recommended. After the caulk has been applied, it can be smoothed with a putty knife to improve its appearance.

Today’s Homeowner Tips

The most conscientious professionals will often go the extra mile and stipple the wet caulk with a wet paper towel. This allows them to create textures in the repair that would be very difficult with a smooth tool like a putty knife.

How Do I Match the Color of My Repair to the House?

Undoubtedly, the best way to repair as seamlessly as possible is to have special paint made just for the repair. The pros will typically do this by removing a section of siding and taking it to a paint store with computer-matching machinery.

These machines are available at nearly all large home improvement retailers as well as specialty paint stores. This is not necessarily just as simple as removing the siding, however, as the sample should be carefully selected. Color matching computers scan the color sample (in this case, a section of siding from the home) and determine which mix of colors are necessary to match the siding color shade.

However, these color-matching computers cannot distinguish faded siding from shadows, so the sample should not include any texture if possible.

Today’s Homeowner Tips

If a section of siding is used for the scan, in most cases the paint will be too dark as the computer will mix the shade of the shadows caused by the texture with the actual color of the siding.

This begs the question “how can the installer use a section of siding for color matching when the siding is textured?”. The answer is surprisingly simple. Since vinyl siding is colored all the way through the material (as opposed to having the color just on the surface), the solution is to scan the backside of the siding. This side will be very smooth and will be much less likely to confuse the computer.

How To Repair a Loose Vinyl Siding Panel

As mentioned earlier, in most cases professionals will avoid repairing vinyl siding altogether and simply replace the damaged section. In other cases, the siding panel has simply come loose from the structure and just needs to be re-installed. The process is essentially the same for both projects, so we will discuss them both.

Although it is obviously possible to make spot repairs on vinyl siding, generally speaking, the fastest and easiest way to make the repair (at least for professionals) is to simply remove and replace the panel(s). This is because the siding will generally have a wood grain texture, which is extremely difficult to replicate with fillers, such as fiberglass.

Since the siding section above the repair must be loosened to access and tighten the nails for the section below, we will discuss the process of removing the damaged siding and replacing it, using the same tools and methods as the professionals.

Here are a few common tools used in repairing vinyl siding, but others are available:

  • Pry Bar
  • Flat Bar
  • Siding Removal Tool (special tool for detaching one panel from another)
  • Hammer
  • Sharp Utility Knife
  • Shears
  • Siding Nail Punch

Removing the damaged panels is simple, but care should be taken to not damage good panels in the process. This is often done by using a siding removal tool, often available at home improvement stores.

This tool has a thin, curved blade designed to slide behind a siding panel and disengage the locking tab from the panel below it. This avoids having to apply greater force on the surrounding panels, reducing the chances of accidental damage.

After the damaged panel has been unlocked from the panel below it, the panel can be gently raised to allow the use of a flat bar. A flat bar is usually a short (12”-18”), flat pry bar with a hook on one end and a sharp edge on the other. Usually, the sharp edge will also include a nail removal notch.

If a panel is not damaged but just loose from the fasteners, sometimes (especially in very warm weather) the section above the damage can be bent upwards enough to allow new fasteners to be installed. This usually requires a very long nail punch, which is long enough to allow a hammer swing to set the fasteners.

In these cases, the old fasteners are usually just driven up flush with the wall and new fasteners are used in their place. In these situations, once the new fasteners are installed the siding sections are snapped back into place.

In cases where the siding above the repair cannot just be bent out of the way, the siding surrounding the damaged area must be completely removed and re-installed.

To remove a panel, the flat bar is slid behind the panel being removed, between the locking tab and the wall. Gentle pressure is then applied to loosen the fasteners. Fortunately, most installers used roofing tacks, which tend to come out easily. 

Today’s Homeowner Tips

If the fasteners holding a section of vinyl siding have loosened, it is usually the result of the wrong fastener being used to install the siding. Many professionals will install vinyl siding with ring shank or screw shank nails as they are very unlikely to loosen over time.

After the fasteners and the damaged panels are removed, the area should be inspected for any water damage or tears in the house wrap (if the home has it), which is fairly uncommon if the home is older.

If the house wrap has been damaged or must be removed temporarily to make a repair, it can be re-taped, installed with button cap nails, or stapled back into place. However, any fastener used must be weather and corrosion-resistant.

On older homes, the house may have several layers of tar paper (the underlayment beneath asphalt/fiberglass shingles) instead of house wrap.

This was common before house wrap was available, and it was usually installed with staples. If the home being repaired has tar paper, repairs can be made using the same material if it is more convenient than using house wrap.

The final step is to replace the siding panel. Horizontal lap siding is installed from the bottom up, much like a shingle, so the next step is to lock the new piece of siding to the course below it by deploying the locking tab.

Then, using gentle pressure, the new piece is lifted and nailed in place using a galvanized roofing tack, or other weather-resistant fasteners. These must not be driven up tightly, however, as this will cause the piece to buckle when exposed to intense heat or cold. Most manufacturers require about ⅛” gap between the head of the fastener and the siding, but each manufacturer will have their own installation directions.

As a rule, the new section of siding should look exactly like the original, but should it become necessary to overlap two pieces horizontally, it is important to keep any vertical joints separated by at least 6” to 8”. This will allow the siding to shed water more easily and will often prevent water from curling behind the siding. The same procedure is then used to install each subsequent course until the project is completed. 

Can I Repair My Own Vinyl Siding?

In most situations, a do-it-yourselfer with a few tools can repair their own vinyl siding. Using the processes described, making repairs to vinyl can be simple and cost-effective. 

Non-professionals, however, should consider the inherent dangers of using ladders and other tools often involved in vinyl siding repair projects.

Today’s Homeowner Tips

Sometimes, even though the repair is simple, hiring a professional is the prudent option. These professionals will not only have all the tools needed to complete the project, but the experience to use them safely.

However, for those homeowners with the tools and the experience, repairing vinyl siding can be a very rewarding and confidence-boosting project.

Editorial Contributors
avatar for Matt Greenfield

Matt Greenfield

Matt Greenfield is an experienced writer specializing in home improvement topics. He has a passion for educating and empowering homeowners to make informed decisions about their properties. Matt's writing focuses on a range of topics, including windows, flooring, HVAC, and construction materials. With a background in construction and home renovation, Matt is well-versed in the latest trends and techniques in the industry. His articles offer practical advice and expert insights that help readers tackle their home improvement projects with confidence. Whether you're a DIY enthusiast or a seasoned professional, Matt's writing is sure to provide valuable guidance and inspiration.

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