Did you know that 25% of heat loss during winter is a result of cold draughts seeping through your window frames? Professionally applied window caulking regulates cold air and moisture infiltration. 

Caulking is an essential part of home maintenance. It’s important to do your research before taking on this type of project by yourself. So, keep reading for some expert advice.  

Understanding the process will help you achieve work that’s done properly. South shore caulking in particular comes with its own challenges. Knowing what to look out for will go a long way to a guaranteed good job on your windows.

The Dos of Caulking Windows

Let’s discuss some standard tips that you should do when caulking windows.  

  • Do remove old window sealant. This allows the new product to adhere to the surface. You might need to use a solvent to clear away all traces of the old caulk.

In this video we remove a sealant from a window.

Shortcuts don’t actually save time. Applying new sealing material over old caulk doesn’t work. The old caulk will shrink away and the new caulk will come right out with it.  

  • Do apply the new sealant to a clean surface. Window surfaces mustn’t have any dust or any particles contaminating them. Use solvent to wipe the areas clean before beginning the re-caulking process.

It’s important to use the correct solvent. Look for one that doesn’t create stains or prevent adhesion with the new sealant. A product such as Methyl Hydrate is a good option.

In this video we clean the surface:

  • Do use the right caulk. Window caulking is most effective when you use high-quality products. Sealing agents work hard against many different conditions and need to last a long time.

There are a few different sealant products available, so you’ll need to make sure you get the right one. Here is some information about the product we use :


  • Do complete the tooling to give the window caulking a sure finish. It forces the sealant into every section of the surface, making it adhere properly. Tooling presses out hidden air bubbles or invisible gaps in the sealant. 

Additionally, it makes the job look neat and professional. Tooling smoothes and levels the appearance of the caulking product. This gives away whether the job was professionally done.

In this video watch how we tool a caulking joint.


This is a brief run-down on the basic requirements of window caulking. If you’d like a more in-depth guide, you can find out how to apply silicone caulk here.  You don’t want your window caulking to look amateur or messy. 

The Don’ts of Caulking Windows

Applying caulking is one thing. It’s another thing to know exactly what you shouldn’t seal. Your home’s envelope is important in maintaining the lifespan of the structure. And, it reduces your home’s energy consumption

Certain built-in vents protect the structure of your house from moisture damage. Do you know what these vents are? It’s important to be familiar so that you don’t mistakenly seal over them. 

Don’t caulk weep holes. These are small vents or openings in bricks that allow for proper airflow and water release.  Don’t seal them up because they are a required part of the structure preventing rust, mold, and rot.

weep holes

Don’t caulk trimmed-out windows. You don’t need to because the trimming is designed to drain moisture away from the window. So, don’t seal the joints, or you’ll be trapping water inside. 

Don’t caulk your windows shut. Take note of all the window sections. Some parts move so that the window can open, if you seal the moveable parts you might damage the window itself. 

Additionally, The ledge above the window frame has a drip edge which works to keep the frame dry. So don’t caulk the top of your windows. 

Window flashing

What You’ll Need 

You’ll need a suitable caulking gun that provides a smooth, consistent bead. A dripless, smooth-rod type, with a spring mechanism, is the one to go for. 

The caulk needs to be applied evenly with an angle of 45°. You’re not just filling in a gap between two surfaces, the material needs to bind the window to the wall’s surface edges.

Another necessary item in your toolkit is the backing rod. This building foam creates a backing when gaps are wider than a quarter inch. And, it prevents caulk from sinking too far into larger spaces. 

Here’s a quick list of what you’ll need to caulk a window:

  • A utility knife or scraper to help you remove the old caulk
  • Solvent for cleaning 
  • Caulking gun
  • Backing rod
  • A small spatula for tooling
  • Silicone-based caulk of the correct grade and color

It’s recommended that caulking projects get completed in spring, summer, or fall. However, if you go with a silicone-based caulk you can do them in winter too. All you need is a dry environment and temperatures between -20℃ and 43℃. 

Here are a few reasons why silicone-based caulk is the ideal option for the south shore of Montreal: 

  • It’s flexible, expanding and contracting in different weather conditions 
  • A wide range of colors are available 
  • It’s easy to remove, replace and apply
  • Cleaning it is easy
  • Silicone-based caulk can be applied to a variety of different surfaces
  • It has a long lifespan of 10 to 20 years and it can be applied in any season

Hiring a caulking specialist may save you time and expense in the long run. A specialist will give you a guarantee on your caulking. This gives you peace of mind that your window caulking will look neat and last as long as it’s supposed to.  

A Final Word on Caulking 

If eyes are the windows to the soul, then windows are the eyes of your house. It’s a silly comparison, but it means that windows should be attractive. How your windows look determines the general appearance of your home. 

Window caulking is straightforward, but that doesn’t mean it’s an easy job to get right. Proper caulking should blend into the window, being all but invisible. 

Window caulking is not something to neglect. It’s important for the look of your home, as well as its general upkeep. If you’d like an expert opinion, you can get a free quote here.