Weep vents are strategically placed at the bottom of exterior masonry walls, directly above the foundation, shelf angles, and window or door lintels. They should also be placed at the very top of a wall cavity to promote optimal drying and convection.
Installation: Best Practices
It's essential that weep vents are placed at regular intervals along the base of the wall and above windows and lintels. This ensures optimal drainage and prevents water accumulation in any one area. Typically, they are placed every 45-90 centimetres for optimal use.
A 2022 National Association of Home Builders report says homes missing proper weep vent installation face a 50% higher chance of long-term damage. That's no joke! Weep vents in brickwork are your wall's BFF, keeping building envelope issues at bay and your home looking sharp.
Weep holes are drainage and ventilation openings typically placed near the lowest points of a structure to allow moisture to escape. Their exact placement depends on the building component, varying across exterior masonry walls, windows, and retaining walls.
They may be designed to drain the cavity but prevent the ingress os wind-driven rain. The IG Weep-vent provides all functions and can also be used as a perp ventilator. Vents are required at 450mm intervals and each opening should have at least two weep holes.
Plastic or Metal Weep Vents — Prefabricated vents, often made of PVC or stainless steel, slot into the mortar joint. They maintain a small opening for water egress while featuring a grill or slat design to discourage blockage by dirt or insects. Many of these vents are colour-matched to the brick for a discreet finish.
The weep holes also provide wall cavity ventilation. Drainage and ventilation help prevent the growth of structurally damaging and unhealthy mold and leaks into a home or building.
Yes, weep holes can cause leaks, but usually only if they are blocked, incorrectly installed, or overwhelmed during severe weather.
Weep hole spacing varies depending on the structure, but for standard brick veneer and masonry walls, code requires a maximum spacing of 33 inches on center. However, experts often recommend spacing them every 16 to 24 inches for optimal drainage.
Weep holes are commonly used by snakes for a shelter site over winter! The weepholes lead to the cavity between the outer brick layer and the internal wall of the house.
The Weep Vent should be spaced at no greater than 900mm centres to meet N.H.B.C guidelines, which state, “weep holes are recommended to be sited at every 450mm maximum with at least two per opening above all windows and doors.”
Yes, a shower, sink, and toilet can absolutely share the same vent, often referred to as a "wet vent" configuration. This setup—where the sink drain also acts as the vent for the toilet and shower—is highly efficient and saves space, but it must strictly follow specific plumbing codes regarding sizing, slope, and distance.
Trickle vents are required in doors and windows to new build homes or new extensions unless there's a suitable alternative method of background ventilation meeting the current Building Regulations.
Yes, mice can easily crawl through vents and ductwork. Because their skulls are highly flexible, a mouse can squeeze through any opening that is just the size of a nickel or a pencil (about 14one-fourth14 to 38three-eighths38 of an inch).
Yes, bugs frequently get into homes through weep holes. These openings—designed to let moisture escape brick walls—act as a 24/7 highway for ants, roaches, spiders, and even rodents.
If water does not exit the weep hole, or if visible debris is present in the weep hole, cleaning is necessary. Figure 3. Pouring water into the window track and checking for drainage at the weep holes can reveal if weep holes are draining properly (Source: PNNL).
This research demonstrated that even under truly extraordinary conditions water rarely enters the weephole and even if it does it cannot be blown high enough up in the cavity to create internal damp problems. To understand why, it's important to look at the details of a correctly constructed cavity wall.
Concrete is not waterproof. It is porous by nature, and over time — especially in older homes — concrete foundation walls absorb moisture from the surrounding soil. When hydrostatic pressure is sustained, water doesn't need a crack to find its way in.
Signs of an Underground Water Leak
Mold is generally at its worst from early spring through early fall (specifically July through October), peaking during the warmest and most humid months. Mold thrives in warm temperatures (60∘F to 80∘F) combined with relative humidity levels above 60%.
If brick weep vents become compromised, several issues can result such as rot and decay, mold and mildew outbreaks, and pest infestations.
Research has shown that English Ivy can eliminate up to 78% of airborne mold within 12 hours. This makes it particularly useful in humid areas like bathrooms and basements where mold growth is more common.