Proper caulking around windows helps keep homes and properties damage-free for a long time. Caulking around the windows involves sealing cracks, weatherproofing the property, and preventing several external risks such as moisture intrusion.
All caulk has a shelf life, and you need to replace old caulk after 5-7 years. Outdoor caulk typically only lasts 3-5 years since it is exposed to the elements more often. Without replacing the caulk, the risk of water damage to the window sill increases.
Whether you are looking to seal off all the joints around windows or are replacing an old window, removing the old caulk sealant will ensure that the new caulk effectively protects your home from heat leakages.
Removing Caulk From Window Frames
Whether you are looking to seal off all the joints around windows or are replacing an old window, removing the old caulk sealant will ensure that the new caulk effectively protects your home from heat leakages. Learn about the following steps below.
- Soften the caulk before removal
- Remove old caulk without damaging the window sill
- Clean the window sill
- Decide what type of caulk is best for you
- Apply the new caulk
Soften Dried Caulk
Before removing the caulk with a putty knife or pliers, you will need to soften the caulk. If you try to remove the caulk without softening it or not removing all of it, you risk damaging the window sill. The best two ways to soften dried caulk from window frames are with heat or by use of a chemical compound to weaken the integrity of the caulk sealant.
Softening Caulk Sealant With Heat
This method mainly involves using a heat gun or a hairdryer to soften the old caulk from window frames. It generally requires a higher proficiency level because a slight oversight can badly damage the window sills or even harm you. So, remember to take the necessary precautions when using this approach.
Turn the hairdryer up to high and keep it 6 inches away to soften dried caulk sealant with heat. It should take ~30 seconds for the putty to form a malleable clay-like substance for removal. But if the hairdryer and heat gun do not begin to soften the old caulk, you may need to turn to a chemical compound.
Softening Caulk Sealant with Chemical Compounds
If heat fails to work, there are several other chemical options to use. This method mainly involves using any known caulk removing solvents such as rubbing alcohol, vinegar, and sometimes warm water. The caulk softening process generally requires that you rub the caulk down by soaking a rag in the rubbing alcohol or vinegar solution. Make sure to wear gloves when using the solution so it does not touch your skin.
We recommend Motsenbocker’s Lift Off Caulk Remover when going with this method.
Stripping The Old Caulk & Cleaning The Windowsill
There are few ways to strip the pliable caulk. Putty knives, utility knives, and pliers are all good options to remove old caulk with. The first two are suitable for stripping and peeling, whereas pliers work best with caulk with multiple layers. These tools are particularly sharp, so you need to be cautious when handling them.
After the caulk is primarily removed, there will still be caulk residue. Make sure to clean this off before applying a new layer of caulk. Failure to remove caulk residue usually reduces the effectiveness of the newly applied sealant. Use sandpaper for wooden window sills and brush for metal window frames.
After cleaning & scrubbing the window sill, wash it with soap and water. Once it has completely dried (ideally during a nice warm sunny day), you can reapply the caulk.
Selecting A New Type of Caulk
Before you begin ripping out the old caulk, you need to be ready to replace it. The ideal condition to caulk is when the weather is dry to prevent moisture and water from ruining your caulk.
There are so many types of caulk in the marketplace, and not all of them provide the best protection against moisture intrusion and air leaks around the windows. Below are our top three recommendations for you to consider when selecting a new type of caulk:
- Silicone Caulk: This is a type of caulk sealant that is purely made up of silicone material. Its inorganic nature makes it both waterproof and robust enough to withstand extreme weather conditions. This property further makes silicone caulk highly adhesive (except on wood surfaces), can last up to twenty years, and is ideal for sealing exterior window joints. The best way to remove silicone caulk from aluminum window frames is by applying a commercial sealant remover before scraping it away.
- Acrylic Latex Caulk: This type of caulk comprises synthetic materials that resemble natural latex. It is a water-based type of sealant that is paintable and mainly intended for sealing molding gaps around interior windows (especially along with wood trims). Acrylic latex caulk usually forms stiff joints when dry. Using isopropyl alcohol or a commercial caulk remover is the best way to loosen and remove this type of caulk.
- Butyl Rubber Caulk: Due to the Plastic-sealing compounds, butyl rubber caulk is an excellent caulking option for outdoor window frames. It is highly resistant to aging, UV radiation, and moisture. Its chemical makeup makes it resilient, paintable, and perfect for masonry siding. Unlike the other two, this type of caulk is best removed by a combination of heating and scraping.
Applying The New Caulk
Freqently Asked Questions
Caulk can be softened and prepared for removal by either using a heat gun 6 inches away from the caulk or chemical compounds. Choose a reputable caulk removal product, wear gloves, apply and let the solution soak before scraping.
Start off by scraping any caulk you can with a scraper or knife. If any caulk remains, wear gloves and apply a caulk removal product to the remaining caulk.
Yes, the acid found in vinegar helps break down caulk materials to a point where you can scrape or scrub the rest off.
Yes, rubbing alcohol is a good first step to softening caulk from a window frame. This will loosen the caulk and make it easier to scrape.
Using a heat gun 6 inches away from caulk. Using a heat gun and then scraping the majority will produce the quickest caulk removal. After doing an initial pass, go over the caulk with the heat gun again and scrape with closer detail.
It’s highly recommended to remove the old caulk.
- New caulk sticks better when removing the old caulk
- Final result looks cleaner
- Removes any potential mold or dirty caulk
Most caulk removers are not recommended on painted surfaces. Mask off any painted areas if you plan on using caulk remover around any surfaces that are painted.
You might start noticing leaks or drafts coming into your home. In less serious cases, you may visually see that the caulk is starting to break and dry out in certain parts. It’s a good first step to test the caulk by trying to pull it with your fingers. If the caulk starts to come off easy, then it is time to think about removing the caulk around your window.