weep holes in brick

DexterII

When we added onto our house several years ago, I installed weep holes with screens in the bricks, and since this particular area was to have flower beds up to the house, I simply made sure that the soil sloped away from the house, and that the screens were above grade, and life was good. Now we are going to build a small patio with some pavers that we salvaged from another job, so the question that popped into my noggin was whethere there is a specified distance, i.e. minimum or maximum, that the weep holes are supposed to be above the ground, or, in this case, the pavers.

stuart45

Your codes are probably different to ours, but as long as they are above ground or paver level to allow water out it should be OK.

Thurman

As stated, local codes will be different. Case in point: In my are there must be "weep-holes" a minimum of six inches (6"), of ground grade, and between six inches (6") and twelve inches (6'--12") of the top course of brick also. Now we have a new rule/amendment to this code: Hollow tubing will be required to be put into the "weep-holes" starting Jan. 01, 2012. What's the difference between the open weep-hole and the hollow tubing?

JoJo-Arch

Weep holes are supposed to do exactly what they mean, let water out from the wall cavity to the outside. For this to work, there must be metal or membrane flashing at 45 Deg. from the inside wall skin, across the cavity and checked into the course at bottom of the weep hole. Once installed, weep holes cannot be raised, as you can't get access to the internal flashing. So the outside finished level must be below the bottom of the weep hole. Bricks are actually porous, as are concrete blocks, and with a brick veneer wall, the bricks subject to direct rain, will absorb moisture and carry through the brick to dribble down the inside of the brick. At the bottom, this 'weeping' will be caught by the flashing barrier and directed to empty out from the weepholes. Water can also arise from condensation in the cavity if warm, moist inside air touches the cold outer brick skin, and again, dribbles down the inside of the brick. Blocking a weep hole causes water to build up and transfer to the inside wall, causing damp and mould to grow. Worse, it could also start salt efflorescence and spalling of the brick surface.

DexterII

Thank you. You're right; I'm sure that it will vary somewhat by lcoal code, so I'll ask my local inspector. I was actually going to do just that this morning, but then things changed, and I didn't have to go for the other thing, so thought I'd post here. All I was required to use was a screen between the bricks, and that passed at that time, but now that we are putting pavers there I figured I may as well get the elevation where it is supposed to be. I don't know about the hollow tubes, but if I can remember, I will ask Bruce about them when I talk to him.

jomama45

Likely, the hollow tube language was merely added to keep folks from using rope, which was common years before. The rope does OK at wicking water out of the brick but, especially in a case like Thurman's where the code recognizes the value of air circulation via upper air holes as well, havign a clear hole that can pass small amounts of air is superior.

As for the height, I can't think of any reason why simply keeping them above grade would not be enough. If you're concerned about it, you could always drill an additional set of holes in the joint in the course above, but it would likely be unnecessary.

TrapperL

Most building codes say that the grade must be 8" below the finished floor. Considering that most brick lugs are 1 1/2" deep, the grade or dirt should be at least 6 1/2" below the weep holes. The slope should be 6" in 10 feet in most codes. Around here, that screen would get you a big red tog and a failure at inspection. Nothing is allowed in the weep holes. We see a lot of the pest control folks stuff the holes with steel wool which filters out a lot of dirt causing the weep hole to become plugged. A good mason on new work will leave out every 3rd brick and when the job is finished, will come back, clean all of the excess mortar from the lug and install the missing brick with zero mortar on the sides making the weep holes.

JoJo-Arch

Hi, I'm getting the impression from reading the posts that cavity flashing is not used or common in the US. No one has commented on flashing. If this is the case, weepholes are useless and may as well not be provided, as all they're doing is letting in insect vermin like termites, ants, wasps, snails and the like. If no flashing is provided, water will simply go past the weepholes to a lower brick layer, and no water will come out of the holes. Again I ask, am I missing something?. In parts of Australia, code requires a fine continuous SS mesh be provided in slab construction to stop termites penetrating the weep holes and feasting on the timber studs. Weepholes stop one problem and create another. Cheers from Melbourne, Australia. Enjoy the day to come.

jomama45

You have to remember that the majority of posters here aren't in Texas, and subsequently don't have a slab-on-grade foundation. On a home with a crawl space or full basement, you have the height of the floor joists, rim, floor sheating, finished floor material, etc... plus a drop down brick ledge to the height. It's not uncommon for that dimension from grade to finished floor to be 24" plus. What really matters though is the finished exterior grade to non-treated lumber, which is usually the wall sheating in this scenario. Here in WI, the min. is 6".

Not sure what a 1 1/2" brick lug is either...........



Yes, base flashing is required here with weep holes, at least in all the codes I've seen. Here, we have minimum height requirements for the flashing, as well as the material used for the flashing.

DexterII

Sorry if I injected any confusion when I said that I only used screens. I was trying to picture the hollow tubes at that point, and skipped past the base flashing. Anyway, yes, I did provide a base flashing as well, which was inspected and approved at that time. However, for what I am doing at this time, I assumed (apparently correctly) that the weep holes were the affected point of reference. And, as an update, for whatever it is worth, I talked with my inspector this morning, and he said that as long as the weep holes are visible, even if the pavers or grade are at the bottoms of the holes, it meets the requirement. I am in MI.