Water infiltration through windows and doors

Water infiltration can be a major problem that requires attention, care and fast response. An infiltration can occur when melting snow or rain water slides on the walls, roof and other building components looking to find its way in.

The damages of water infiltration

Any openings in the envelope of your home could be promoting an infiltration that can result in:

  • Damages to your home or building materials and contents.
  • The appearance of mold, rot, and fungi.
  • Health problems such as asthma, allergies, difficulties breathing, and pulmonary infection.

Caulking around the windows and doors

Water damage to your home or building can be costly and may compromise the integrity of a building. At calfeutrage Apex, we advise our customers to be aware of any deterioration of the sealants and caulking around the windows and doors. Caulks and sealants protect the home against water infiltration that may occur if the home has one or more openings such as gaps, cracks and holes.

How to detect water infiltration?

Water can enter from different places. Walk around your home and inspect these places:

  • A crack in the foundation walls and plaster.
  • A broken or dysfunctional French drain.
  • A damaged concrete slab.
  • A roof, if it is due for replacement, defective, or poorly protected.
  • Doors and Windows – that are no longer airtight due to loose or deteriorating caulking.
  • Exterior sidings – If they are not well sealed.
  • Brick joints that are no longer waterproof.
  • Gutters that are clogged or dysfunctional.

This article will talk about water infiltration due to poor, deteriorated, old or non-existent caulking.

Window water infiltration

It is crucial to regularly inspect window caulking to ensure that the sealant joints are airtight and waterproof. Any crack or gap around the window can potentially allow water to drip through the window frame in small amounts and at a constant pace over a period of months or even years before it is noticed/detected.

Be sure to check your sealant joints if you notice leaky windows, water in or around your window or on the surface of your interior windows sill. Do not forget to inspect your basement for window leaks.

Watertight window and door sills

When the expansion joint of a window sill is done with mortar, it is destined to fail as the mortar has no flexibility characteristics. Once a micro crack has formed, it becomes an entryway for water and melting snow. As soon as the temperature increases below the freezing point at night, ice formations will expand and increase the size of the gap, leading to a crack that will dig its way all the way down in the masonry.

By replacing the top flat expansion joint with flexible caulking, it will allow the window sill’s stones to expand and contract with the temperature fluctuation and remain sealed just the same.

The water around the exterior door.

The caulking of your exterior doors protects against water leakage resulting from the presence of water around the doors or by heavy rain. ( You may also notice water infiltration under the front door, patio door or back door if your weather stripping has been torn or ripped). Water infiltration through the bottom of the door is pervasive since most people neglect to inspect the waterproofing sealant joints for gaps or cracks around the doors.

Make sure your exterior siding is watertight.

Unnoticed water damage can easily hide behind the siding materials without being detected. Long ongoing water infiltration can cause big enough damage to compromise the building’s integrity.

To create a water-resistant building exterior, caulking should be applied around openings that go through your sidings such as trim boards, window frames, lights, electric outlets, thermo pump entries etc… Any cracks, nail holes or gaps must be caulked as well, in order to prevent water from seeping beneath the siding.

*** To allow water to escape or exit the building, caulking should not be applied to the bottom of the siding, window weep holes or trim boards above the siding.

Water infiltration through expansion joints.

Most expansion joints are vertical joints that run along 2 masonry walls from top to bottom on high buildings above two levels or between 2 types of masonry (Ex: 2 different size bricks). If the joint is done with a mortar, it is prone to split prematurely.

An application of high-quality and greater flexibility sealant between the two brick walls will allow movement and prevent a joint from splitting.

The sole application of caulk in the expansion joint is not merely enough by itself. The caulker must properly tool (shape, tighten) the sealant material all along both surfaces to ensure a perfect waterproof seal.


  • Humid basement
  • Water inside double pane of a window
  • Heavy condensation in your windows
  • Mould spots on your walls and ceilings
  • Water accumulation on your floor
  • Musty odours
  • Humidity under windows
  • Paint that is peeling off
  • Moisture on the ceiling
  • Cracks in the foundation
  • Weak brick joints

Finding a long-term solution against water infiltration: CAULKING !!!

As we mentioned earlier, water can infiltrate your building through the smallest holes or cracks. Unlike the rare event of a one-time massive and noticeable infiltration, slow seepage of water through tiny holes or gaps over a long period of time may go unnoticed for months or even years and cause massive and expensive damage.

The windows, doors, sidings and roofs protect your home against the weather elements but can not prevent water seepage through small gaps found around these elements. Therefore, caulks and sealants are essential to waterproofing your structure.


UV rays, snow, rain, ice, extreme heat, air pollution, dust, contraction, and expansion of structures deteriorate the seals around your building. High-quality caulking products have to be replaced every 10-15 years to maintain their ability to properly waterproof your home.

It would be best to always remember to inspect the caulking joints every couple of years.

Calfeutrage Apex is waterproofing joints on the south shore of Montreal.

Caulking, sealing, and waterproofing buildings is our main expertise! Our caulking inspector, a graduate of ACQ (Association de construction du Québec) and a member of the APCHQ, inspects your building and provides a detailed report of every building caulking joint that is faulty and has to be replaced. Our reports are thorough and precise and include the proper colour match of the caulking product most suitable for each building element.


Located on the south shore of Montreal, calfeutrage Apex caulks condo buildings, residential, commercial, and industrial buildings as well.  We follow the highest standards of the construction industry. We execute each project to satisfy our customers while following the proper steps of caulking windows, doors, expansion joints, balcony joints, roof joints, lights, electric outlets, window door sills, siding, masonry.

Get in touch for a free quote today: 438-288-0338