How It’s Done: Exterior Caulking

by | May 31, 2019 | Knowledge Base, Uncategorized

While caulking can often be overlooked in the grand scheme of condo maintenance, caulking can be an easy and budget-friendly way to solve some common problems within your condo.

For one, it helps to save money, energy, and ultimately the environment.

It also keeps residents happy and provides additional protection against water leaks and mold growth.

When properly applied, exterior caulking should last around 10 years or so depending on the weather, substrate, and type of caulking used.

Improper application of caulking may not only nullify its intended benefits, but may also lead to more damage within a structure – especially in the case of water leakage.

Here is a glimpse of an actual re-caulking project by ArmourCo.

We were contracted to fix the caulking at a condo due to complaints of water leakage. The picture below is one example of the windows that needed to be redone, and why.

Soft and Peeling

The vertical area on the right is soft and easily peeling as there is a gap between the window frame and brick that needs to be filled with a properly fitted backer rod and then caulked over to reduce the 3-way adhesion between the surfaces to 2-way adhesion.

Improper Application

It is vitally important to take into account the different types of substrates involved in a caulking project. Simply picking out any type of caulking and applying it will likely yield less than favourable results. There are different types of caulking that are best suited for wood on wood, glass on aluminum, brick on aluminum, and so forth.

In this example, we have glass (the window) up against aluminum (the window frame).

Because aluminum and glass expand and contract at different temperatures, we will need to select a caulking that adheres to both of these surfaces that not only provides an exceptional seal, but is also flexible and durable enough to account for the shifting of the surfaces.

Due to the thinness of the material, there is not enough surface area to achieve the ideal amount of adhesion on both surfaces. To make up for this, you will need a skilled caulker to properly lay a cap bead. This type of application lays a bead that makes up for the lack of surface area with a larger than normal sized bead.


The bottom caulking here needs to be replaced as it is cracking due to weather, UV degradation and time.


For all surfaces in this project the old caulking is removed with a blade, thoroughly cleaned with chemicals, repainted, and then replaced with all new caulking.

If you suspect that your property is due for a new caulking upgrade, please contact us for a consultation.