Insulation does not itself cause mould growth. But when conditions are right, particularly trapped moisture and perhaps temperature, mould growth will be encouraged in and on buildings. Allows passage of moisture up to its 2-1/2” height, important in the event of mortar droppings at bottom of cavity. It is important to maintain a clean, open cavity for weep holes to function properly. Low fiber density allows air to move freely through the product to help promote drying. The length of time moisture remains is in direct proportion to the amount absorbed into the materials. A bed joint of mortar needs to be re-spread in front of the air vent material (e).
Flashing at the Base & Weep Holes Featuring master mason Bryan Light, the “Brick Masonry Techniques for Builders” DVD …SDS Documents for MTI Drainage Products – Masonry Weep Vents Safety Data Sheet
Standard weep vents are 2.5″ x 3.5″ and 0.375″ thick. Available in 2 foot lengths and packed 50 pieces per bundle. When the wind-driven rain penetrates the veneer wythe, the cavity allows the water to drain down the back face of the brick. This article provides details about the importance of providing proper drainage for brick veneer walls. I think the weep openings in the veneer wall shown above, though properly located, are probably not working. Also suitable for top of wall venting. However, it was not necessarily all the water, always through the weeps, or a fast process. Mortar is displaced to allow for wee placement (c), and the air vent material is placed (d). Finally, a masonry unit is laid to the air vent material and into the bed joint of mortar (f). The masonry wall air vents should be spaced every third brick head joint, one to two courses above the bottom of the cavity, and above the weeps.
This may move moisture-laden air (i.e. Available in a large range of colours to blend with the masonry and mortar material. Featuring an integral front grille to prevent the entry of large nest building insects into the cavity. Is there a product missing from our list?
The intersection of the roof and bottom back side of the parapet is another moisture management detail with numerous roles. One should not be misled by the term ‘decorative;’ it is also a moisture-diverting detail and a ‘roof’ for the wall and windows below it.
There is a misconception patterns on the exterior of the building envelope veneers (e.g. In truth, their primary function is protection. Further, their proximity to one another joins them into one, unified moisture management risk zone. The explanation is obvious: water runs downhill. If the weeps installed on the radius were to be functional at all, there would need to be an upturned stop flashing at that point of the arch flashing to stop moisture, and the weep would need to be installed at the bottom of the valley in the flashing.
The skill to execute this type of detail is difficult, if not virtually impossible, to find. The gaping mouths in the heads of animals and gargoyles that serve as column caps supporting arches on ancient and medieval structures are actually the weep exits (holes) for the arches’ moisture management system.
This decorative band stone also has an aesthetic appearance aspect. In the case of the stoop platform and steps, the slope-to-drain of the surfaces and their ability to resist moisture penetration is absolutely critical. In all likelihood, it will need to be repaired or replaced before the other adjoining details. It separates the edges of the top surface of the stoop platform from the brick veneer and diverts water away from the intersection of this moisture sensitive detail.
The other obvious concern with windows in this location is security. The attachment and potential movement of these details will result in severe damage to the structure and the ‘at-grade’ details. This is what holistic and sustainable is all about—knowing that nothing is separate, all things are connected and nothing stands alone.
Archovations is CavClear CavQuiet and CavTherm
It should be emphasized, however, the ability of masonry cavity airflow to dry out or remove moisture is extremely limited. Could the brick veneer be removed from the spring line up, flashing and weeps installed and then brick re-installed? Form weep holes by leaving head joint free and clean of mortar, and raking out bed joint at weep hole. Analytical models for veneer wall systems are being developed based on these experiments to further study the vulnerability of this type of construction.
The Importance Of Weep Holes
What are weep holes and why do you need them? We explain that for you here including how to keep pests out and why blocking …
