Blocked or Missing Weeps in Brick Veneer Walls

Masonry veneer wall drainage omission or blockage is risky

Above we illustrate a double-fault at a brick veneer wall weep hole found on a New York Home. This "Do-it-yourself" excuse for veneer wall drainage is too small, placed above the level of the wall base flashing, and is completely clogged.

All of the weep holes we found in this wall were in the same condition.

Faux Bond Courses May Confuse the Identification of a Brick Veneer Wall - but is it a problem? Not Necessarily.

The brick walls of the New York home in our photo at below left contain no weep openings.

Bricks were laid tight against a solid masonry block wall with "faux" bond courses to the left of the chimney and all stretcher brick courses to the right of the chimney.

Walls both left and right of the chimney were constructed with no drainage. Bricks were mortared against the masonry block structural walls of the home with no air space and no drainage provision.

This is a brick veneer on block structure approximately 30 years old. While the mason omitted weep openings, we did not find any evidence of water or frost damage to the brick veneer except at another wall where splash-up from roof spillage had worn mortar joints.

This is a barrier wall design, not a cavity / rain-screen wall designed structure.

Traditional structural brick walls such as at the building shown at above left are comprised of two or more wythes [defined below] of brick laid in parallel and reinforced by bond courses at regular intervals.

Such walls typically include an air gap between the exterior wythes of brick - the wall outside surface, and the wall interior. At above right the mason actually built a brick veneer wall over solid masonry block.

That space allowed water that leaked into the wall to run down the wall interior and drain at the wall bottom - provided that the wall bottom included weep openings or drainage.

At BRICK FOUNDATIONS & WALLS we describe the collapse of the structural brick walled building shown at right.

Definition of wythe or brick wythe

1. Each continuous vertical section of masonry one unit in thickness
2. The thickness of masonry separating flues in a chimney - Masonry Design Manual

If you look at a brick masonry wall, one brick thickness of the wall is one wythe. A brick veneer wall constructed using full-dimension bricks will be one brick wythe in thickness (of the veneer). The total wall thickness will include the veneer wythe plus the thickness of the wall structure itself.

A structural brick wall is normally two or more wythes of brick in thickness, usually separated by an air space of about an inch to form a thicker, more dry wall. In the cross section of the collapsing brick structural wall at above right you can see multiple wythes of brick.

More brick and brick wall definitions and details are

at BRICK VENEER WALL LOOSE, BULGED.

How are brick veneer walls usually supported?

Carson Dunlop Associates sketch (below) illustrates the usual manner in which a brick veneer wall is supported.

On occasion we find an "add-on" brick veneer supported by a steel lintel bolted to the building structural wall bottom.

Details about brick veneer wall support, bulge & damage, fasteners, and repairs for attached veneers on wood frame construction are found

at BRICK VENEER WALL LOOSE, BULGED.

Is it OK to Seal Weep Openings in a Brick Veneer Wall?

Reader question: can I seal off weep holes where flashing is wrong and the wall leaks?

4/18/14 Ted Asked:

[paraphrased]

The weep holes over our windows and doors are leaking into the building interior. I think the flashing was not done right. Can I just close them off to solve this problem?

Reply: no

Ted, I agree that it sounds as if the flashing above windows and doors was omitted or not properly installed or punched or damaged during construction. I can't see how to fix this easily without some exploring into the wall cavity to see what's going on. Check out Carson Dunlop Associates' page top sketch (click to enlarge any image) to see what the flashing position should be.

Keep in mind that even if the flashing is properly installed, if a lot of water is leaking into the wall from higher-up, the water might be running down the wall sheathing and behind the flashing and out from underneath it. That diagnosis is what's needed before we try to fix anything.

Reader Question: wicks instead of flashing and drain openings in veneer walls?

(May 12, 2014) Norma said:

My daughter's house was finished in August 2013. It is located in Oklahoma. The bricklayer did not install flashing behind the weep holes. To make matters worse, the weep holes are less than 6" from the soil. Some weeps are at ground level.... Someone has suggested installing wicks to wick away any moisture. What is your opinion on wicks?

Do you have another suggestion other than removing portions of brick and installing the flashing?

Reply: no

In my OPINION this is a mess. I'm worried that wicks won't allow sufficient drainage, that close to soil is an insect attack risk. If it's not reasonable to lower grade (and slope away from the home), we need to investigate further: is there a basement? can we see the house sills from inside?

Question: interior floor damage after sealing brick veneer weep openings

(Oct 6, 2015) Diana Persh Bogden said:

I had wood flooring installed in a new home for a builder client of mine. The homeowners had a raised concrete patio installed and all the weep holes along the back of the house were covered by concrete after we installed the floor.

Several months later they called the builder and complained that the wood floor about 3 feet deep along the whole back of the house was buckling and heaving. I went to inspect it and attribute the problem to the covering of the weep holes thus preventing ventilation and moisture build up. Am I right.

Reply:

Not exactly, Diana. "Ventilation" in the sense of a moving air current through the veneer wall, or loss of it, may not be the exactly-correct explanation of the buckling wood floor, though there can be little doubt, given the timing you describe, that adding the raised concrete patio and sealing off the veneer weep openings led to the floor buckling.

The purpose of weep openings is to let water out of the veneer wall rather than sending it into the building wall (and possibly floor) structure. That drainage is needed when wind-blown rain (or possibly significant amounts of condensate) in the cavity space between the veneer wall and the exterior sheathing of the wood framed wall behind needs to get out.

I see that more as water drainage than as air movement. Air movement might address or reduce condensation IF there were a lot of air movement but with just weep openings at spaced intervals along the bottom of a masonry veneer wall, there's not much air flow in that cavity space.

I would want a further on-site investigation to understand what happened. I suspect that actual water entered the wall cavity and the floor structure at the bottom of the wall.

If the floor is built on a slab then we can't see into that space without a borescope or some demolition, but I'd bet that if you did look into such a cavity for the case you describe, you'll see water stains (and maybe rot). Water and high moisture can indeed cause severe buckling of a wood floor, more so if the floor was installed without an expansion gap around the floor perimeter.

For the case you describe, I doubt that the floor buckled from normal expansion from normal moisture level variations - otherwise the buckling ought to have occurred when moisture levels changed (perhaps seasonally) even before the patio and outdoor raised slab installation were completed.

I suspect that water from rain penetrating the veneer wall, or perhaps even excess water from the add-on slab itself are what entered the wall and floor of the home.

Also see BRICK VENEER WALL LEAKS in FLOOD PRONE AREAS

...

Reader Q&A - also see RECOMMENDED ARTICLES & FAQs

On 2020-05-28 - by (mod) -

OK Anon,

So for this situation you may want to install retrofit weep hole covers; see the products available at

BRICK WALL DRAIN, FLASHING, VENT SOURCES

inspectapedia.com/structure/Brick_Wall_Weep_Vent_Screens.php

In my photo below the left hand gray plastic weep opening screen is intended for retrofit while the right-hand model is one inserted during new construction.

You want the left-hand model.

On 2020-05-28 by Anonymous

The cut off in the black plastic in image. This image there is a scratches but others have holes done by the drill.

Some of them the upper part of the veneer filled up with morter. Thanks a lot for your help!

On 2020-05-27 by Anonymous

Yes what I did I drilled the clogged the weep holes to remove the mortar from it and while I was doing that, I found the blastic cover got holes and cut off from my drilling. Thanks a lot for your help.

On 2020-05-27 - by (mod) -

Anon

Did you actually pull the entire piece of flashing out of the wall? That seems unlikely and almost impossible. Or did you cut off the flange at the very outer edge of the flashing that was bent down and extended slightly past the face of the wall?

On 2020-05-26 by Anonymous

Hello sir, in my house the weep holes was clogged by mortar I opened it but I am worried because I accidentally ripped off pieces of the flashing underneath the brick any advise will be appreciated. Thanks

On 2020-04-08 - by (mod) -

Anna

One or two sealed weep holes in the veneer is not likely to be critical as long as they're not immediately adjacent to one another. But if I hit my dog mistake I would probably simply try to drill out the sealant that I pushed into the opening.

On 2020-04-07 2 by Anna

Hello, I accidentally sealed a few weep holes on the porch with a MorFlexx Grout Repair. The porch is about 4-5' wide and 3' deep. How do I remove it, and do I need to? The rest of the house is fine. Thank you.

On 2020-02-17 - by (mod) - We pulled out of buying the home,

Stone

It would be helpful to have details about how the stone veneer and wall behind it were constructed, whether or not a drainage plane was installed, and how the veneer is supported, above or below ground, etc.

Properly located and installed weep openings reduce rather than increase damage to buildings, but there are potential issues with or without weep openings, such as for homes located in a flood plain.

No one with any sense would condemn nor approve the wall about which you ask when there's no information about its construction.

On 2020-02-1 by Stone Veneer

We are looking at a home build in 2003, the inspector noted the stone face lacks weep holes. We've read not to install as you may cause more issues.

We pulled out of buying the home, until other inspection issues could be further explored, however this is one we are unsure how to fix.

Really like the home, just debating on how to tackle this.

Stone appears intact w/ intact mortar without any interior issues. What should we be looking forj? Were there types of installation that didn't require a drainage system? Or does this need a rip and replace correctly?

On 2019-10-21 by Anonymous

Anthony,

The article above discusses the problem of blocked or missing or undersized veneer wall drains and

There are retrofit veneer wall weep hole products on the marker

BRICK WALL DRAIN, FLASHING, VENT SOURCES

Essentially you use a masonry drill at mortar joints to make the opening and insert the weep hole screen.

There are limitations in effectiveness of adding drain openings if in-wall flashing was omitted, if the wall cavity bottom was overfilled with mortar, etc.

On 2019-10-21 by Antony

How to rectify the problem of missing weep holes in the house ?

On 2019-05-18 - by (mod) -

Stone veneers need to have a drainage system and the inserts that you talked about her usually good for keeping those openings clear.

But that would not be likely to explain the diagonal cracking. I would look closely at the support for the veneer as well as looking carefully at the foundation itself.

On 2019-05-17 by realcounty1

I have a 2 Story Limestone Veneer Brick home located in Texas Hill Country where I retired. The home is around 8-10 years old. Last 2 years I've noticed a diagonal crack and separation from top to bottom of home on South side. Doesn't appear to be a foundation problem since no jammed doors or windows

. I noticed though that their are no weep holes. Should they(weep holes) be added before re-tucking and pointing the mortar? Also what is your opinion about weep inserts as to keeping insects/varmits out?

James L Gayhart
IMAGE LOST by older version of Clark Van Oyen’s useful Comments code - now fixed. Please re-post the image if you can. Sorry. Mod.

I purchased a 2 story limestone veneer home in the Texas Hill Country in 2015. Home is about 8 - 10 years old. Within last 2-3 years a diagonal crack and separation 1'4 to 1/2 inch has occurred. I don't believe it's a foundation problems since I'm not seeing any weird cracks or having window and door closure problems

. I did notice that no weep holes are present? Should I have them installed along with the damaged motar to be tucked and repointed? Should inserts also be considered to prevent insects, etc from getting in?
IMAGE LOST by older version of Clark Van Oyen’s useful Comments code - now fixed. Please re-post the image if you can. Sorry. Mod.

Question: Leaks & mold growth in brick veneer walls that admit water during flooding

(Mar 13, 2012) WEill said:

if water enters the weep holes during a spell of high water, and allows some water into the building. if the sheet rock is not wet, will mold still grow inside the wall? if so how should i dry it out?

(Feb 18, 2013) Levertis Steele said:

Water rises above the weep holes when it rains in my backyard for several hours. Water seeps in from somewhere and covers most of the room it enters. After the rain stops and the water level outside recedes, the water drains from the room in the same direction from where it came. I thought that it was coming through the weep holes. What is wrong?

Reply: lower the water or raise the house

Will:

Even with a lot of experience with mold detection and remediation in buildings I can't say for certain that mold will or won't grow at a specific location on a house I've never seen. But certanly drywall is very mold friendly. If drywall is wet or even if it's not, if there is water inside a wall cavity that sends moisture higher in the wall cavity to where drywall is located, you can expect problematic mold growth to show up.

You can explore the suspect area for visible mold by making a test cut into the most-suspect location. Check the cavity side of the drywall for visible mold and also check nearby wood framing and insulation.

Levertis:

Periodic area flooding that is submerging a building wall to heights above the top of the foundation wall suggests some more serious steps are needed to control floodwaters, or if that's not going to be reasonable or reliable, to live with water entering the property, structural design changes are needed.

In an area of very limited water and rot problems on a flat site in New York, I addressed a water entry and related rot/insect damage problem by chopping off the bottom two feet of a wood frame wall and building up the wall base with a couple of courses of solid concrete block.

Question: ok to cover up weep openings ?

(Sept 11, 2012) Anonymous said:

I have weep holes located on the 2nd floor of my house. above and below a window and also a few towards the base of the 2nd floor. Can these be covered up?

Reply: no, probably not

Closing off weep openings in a masonry wall, presuming that they were properly located, installed, and flashed in the first place, risks trapping wind-blown rain or other water inside the wall cavity, inviting structural damage, rot, or mold contamination.

Question: Masonry wall weep holes vs Wind-blown rain water entry

(Sept 22, 2012) dena said:

we have water after a blowing rain coming over the brick ledge which sits on the basement foundation .the water did not drain out due to the builder installing the flashing wrong it is on the outside of the tyvak.the moisture caused the vapor barrier to condense and now we have a mold problem. can we remove several couses of brick to repair the flashing?

a builder wants to remove all the brick around the house which is very expensive and money we don't have as we are senior citizens and in bad health.

a masonary man says he can remove several courses by leaving some of the bricks every 5 feet.can this be done?

Reply:

I think your mason may have more experience with brick veneer than the builder, and his suggestion is worth a try. But be careful. 5 feet as the drainage opening interval may be too big a gap.

An unknown is the number and spacing of ties to the wall structure. If the wall is not supported enough and thus cracks you'll end up removing it all. Try working on just one segment at a time and perhaps leave more bricks loose but in place, removing the temporary support ones just briefly during repair and re- flashing. Send me some photos and perhaps we can comment further.

Question: flashing snafus mean leaks blamed on weep holes

4-17-2014 Ted said:

I have weep holes above my windows and door. The rear of the house is exposed to blowing wind and rain. I have leaks in three windows, one easily seen dripping from the top window frame the others I suspect are running down around the edge of the window and coming out below the window from the lower trim, running down the inside walls.

I had the windows caulked and as an add on the contractor, as a favor, added metal wrap to the lentil and caulked around that too. First really heavy wind and rain storm came and now the leaks seem worse. I suspect the flashing must have been run out through the lentil and that wrap and caulk job are the reason it's worse. Am I correct in that thought? Should I take the wrap off of the lentils? How should I check for proper flashing as I had leaks before the wrap and caulk job?

Reply:

Ted, I agree that it sounds as if the flashing above windows and doors was omitted or not properly installed or punched or damaged during construction. I can't see how to fix this easily without some exploring into the wall cavity to see what's going on. Check out Carson Dunlop Associates' page top sketch (click to enlarge any image) to see what the flashing position should be.

Keep in mind that even if the flashing is properly installed, if a lot of water is leaking into the wall from higher-up, the water might be running down the wall sheathing and behind the flashing and out from underneath it. That diagnosis is what's needed before we try to fix anything.

Watch out: Certainly we don't want to just close off weep openings or caulk in the wrong place or we risk either water accumulation in the wall or severe rust and lintel damage.

Question: do weep hole vents extend from foundation to roof line?

4/18/2014 Rodney Thompson said:

Have you ever heard of a weep hole extending in a straight verticle line from the foundation to the roof?

Reply:

Rodney,

A weep opening in a brick veneer wall is placed at intervals and at one or more location heights always including the wall bottom and possibly at higher points in the wall depending on how the wall is constructed.

The open space behind a brick veneer wall is typically intermittently partially obstructed by extrusions of mortar in the veneer, depending on how the wall was built, but hopefully nowhere is the air space totally obstructed across the whole width of the wall - so moisture can find its way to a weep opening for exit.

SO yes the air space behind a veneer wall extends, though irregularly, from wall base to wall top. But no, not explicitly in a "straight line".

The "wall top" may not extend to the roof line - that depends on how the building is designed and how high the veneer wall extends.

Question: dirt coming out of retaining wall drain openings

(June 1, 2014) Kathryn Mundy said:

dirt is coming out of retaining wall weep holes in patio. I have tiny patio that abuts earth -- the top of the wall is at ground level of a row of neighbors that live up a hill behind me. I had this home 15 years. In last month I now have large piles of Dirt at openings of the 3 weep holes (I have photos) .

We recently had 3 days torrential rain; also possible there are mice (I live very near a river in a small town and river redraws rats and mice) also last year neighbor behind me built picket fence at top of wall (the earth behind wall is a dirt path with landscaping that leads out to parking area. What would suddenly be forcing so much dirt to come out of the weep holes at bottom of my retaining wall?

Reply:

Kathryn,

It's common for soil to wash through drain holes in a retaining wall, especially after heavy rains. If the wall has not moved, bulged, cracked, then it sounds as if the drainage openings are doing their job.

I'm not sure why there would be a sudden change, perhaps settlement or a surge in water behind the wall.

To avoid confusing other readers, a retaining wall is NOT part of a building structure, it is a wall built to hold back earth.

See RETAINING WALL DESIGNS, TYPES, DAMAGE

Question: when to close off weep or drain openings in walls

(June 4, 2014) Virginia P. said:

I am converting my front porch into a room. The contractors says we can leave the existing brick walls with the weeping holes in place. He wants to keep the wall, and built over it. Some people tell me we should have the brick wall removed so moisture will not built up and create mold. The contractors says its not necessary. I don't know what is correct. What should I do?

Reply:

Virginia,

I don't understand how your existing porch is constructed nor where the weep holes are located in it. If you are describing drain openings in a masonry wall that is earth filled, over which a porch slab was poured, leaving them in place is harmless. In any event the intent of drain or weep openings is to allow rain or other water penetration to exit the structure. Sealing them, in general, risks future trapped water and a moisture problem or in freezing climates, frost damage.

Question: increasing the length of brick wall weep tubes: owner pouring water behind brick to test for leaks

(July 22, 2014) Anonymous said:
Stucco Tec / I am a brick mason we are laying 60000 brick and using weep tube the home owner has been running water behind are brick to see if the weep tub is working 80% of them are working the others are plugged with mortar that has fallen behind the brick which will happen I am now going to make my tubes longer what do you think is a good idea. Thank You Stucco Tec

Reply:

Anon,

I think the owner is not doing a very good thing to pour water in volumes far greater and at a greater rate than the brick veneer wall design would anticipate - a result risks leaks into the wall cavities, floors below, mold, insulation damage.

It is common for some weep hole openings to become clogged with fallen mortar. If it's just a very few and if weep openings are frequent enough along the wall bottom, it's not likely to be a concern. More important is proper flashing at the wall base to be sure that water is directed out to the weep openings.

However if you detect a clogged weep opening before the mortar is hard-set you might be able to just clear the existing opening or cut it bigger and insert one of the retrofit weep opening products in this article.

Longer tubes at weep openings may still become mortar clogged and certainly you don't want the end of the tube to be jammed up against the sheathing of the exterior wall.

What do you think about using some of the other weep opening products shown in the article above. There are products for both original installation and for retrofit.

Question: how to stop interior wall rot *& plaster damage behind brick walls in Salt Lake City

(Sept 1, 2014) Susanora said:
What can I do to stop the wall rot (interior crumbling plaster & also some crumbling of interior ferrocement) behind my 1938 brick - lath walls?

The brick frame house has no weep holes, and the problem is only on the west side along about a 15 feet section, all above grade. I think condensation may be part of the issue - this is in Salt Lake City and driving rains are not frequent.

I have had the house for 24 years and the problem has been continuous - I repaired the interior plaster several times, then gave up & hung cloth over the mess. No mildew or mold, but it is a significant cosmetic problem. Is there any way I can add ventilation from the inside of the house to the airspace behind the brick? It is so arid here (average humidity 15% - 20%) wouldn't it be possible to ventilate the cavity from inside of the wall?

Reply:

Rot, which refers to organic materials like wood, is caused by a combination of water and wood destroying fungi, often basidiomycetes, sometimes more serious Meruliporia.

The right epair is to stop the source of water entry and to determine if structural repairs are needed.

I'd also look for insect damage in the same areas.

If you think condensation is occurring in the wall from indoor humidity I'd look for and fix any sources of indoor moisture and I'd seal penetrations into the wall such as around receptacles.

I would not try venting the wall cavity to the indoors - you may invite IAQ problems.

I would look at some of the brick veneer drain retrofit products we describe in this article.

Question: why need flashing as well as brick wall weep or drain openings?

(Sept 6, 2014) JJ said:
Why is there both weeping holes AND flashing? Can't water get out through flashing alone? I am not understanding the logic: do they both perform the same function? Thanks!

Reply:

No the flashing would be sealed by the mortar course.

The weep holes are the water exit; the flashing is the water director.

Question: ok to omit masonry wall drainage openings in short sections?

7 January 2015 Anonymous said:
I have a long brick exterior wall. Near the end of the wall is a double door and then just a few more lengths of brick prior to the termination of the wall into hardi-plank. Is it needed to install a weep hole in the brick in this short length. There isn't one currently.

I feel there is plenty of weep holes on this wall on the other side of the door to allow for air pressure equalization, but I don't see how moisture could escape between the door and the end of the wall (moisture can't go up and over the door opening to the other side to travel out of those weep holes).

Reply:

Anon

The weep holes' job is less air pressure equalization and more water drainage.

Obviously we don' t need continuous weep openings at the bottom of a masonry wall, the openings are spaced at intervals. However an individual wall section bordered by other structural elements, that is not connected to drained wall sections, should have its own weep openings even if only one is fitted.

Having a weep hole in even that short wall section would reduce the chances of water accumulation therein and thus related building damage.

You can make a further risk or needs assessment if you can inspect the building interior walls below the section you are talking about - e.g. from a basement or crawl space where you'd look for leak signs, and you can also assess risk by noting conditions outside that increase the risk of leaks into that section of wall cavity such as an un-flashed or leaky window, door, or cracks in the brickwork.

...

Continue reading at BRICK VENEER WALL THROUGH-VENTILATION or select a topic from the closely-related articles below, or see the complete ARTICLE INDEX.

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• STUCCO WALL WEEP SCREED DRAINAGE

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