Retaining wall Autopsy

What we have here is 20 year old landscape masonry which has failed.  Some walls are leaning where corners have broken.  In other places they bulge where the mortar joints cracked and the visible portion of the structure is slowly sliding away from the buried half. The footing appears to be in good shape as there is no sagging or signs of settling. Overall the mortar is in fairly good condition, the wall just wasn’t up to the job.

It is my opinion that water destroyed this wall. More specifically, trapped water due to poor drainage. Freezing can cause similar damage when water freezes and expands exerting additional force. I am fairly certain that this was not the case here as the plants in the planters would not have survived. Also water can be seen seeping out of the broken spots.

The importance of proper drainage in retaining wall construction cannot be overemphasized.  A retaining wall or in this case a raised planter is a container designed to resist a certain amount of force. For example a paper bag is a container designed to hold a load, but if you over fill it, the bottom falls out.  Luckily paper bags are cheap and easy, brickwork is slightly more involved.

Back to the Rain…

So ends a beautiful stretch of spring weather. Imagine feeling like it’s July in April. But now it is back to the rain, the weather Seattle is most renowned for. This weather often reminds me of masonry problems, as many are water based.

Now imagine a bathtub full of water and you open the drain (assuming the drain is clean) that is a lot of water going through a relatively small hole in short order. This example is difficult for me because I get hung up on the fact that water weighs eight pounds and some change per gallon, pressure, velocity losses of the pipe etcetera. It just doesn’t translate well into the way water enters a masonry structure. But the fact remains that you can get a lot of water through a small hole.

So how does water get in? (and what you can do about it)

1)      Down the chimney unless you have a cap installed. Seems like a no-brainer, but it is a commonly overlooked item. Take a look around Ballard, Madison Park, or Queen Anne and see how many chimneys have caps. My own chimney went forty years before it got capped. A puddle in your chimney can soak into porous mortar, transferring moisture into your house, and also greatly reduces the service life of your chimney.

2)      Through defective, improperly installed, or missing flashing. Although flashing (and associated problems) are not unique to masonry construction alone, it is nevertheless a very important part of a masonry structure. Flashing is especially critical around chimneys (roofs are very wet places), but is also important on lintels and copings, really anywhere there is a ledge for water to sit on there should be flashing to keep water out of your house. When water gets around flashing and enters the home, it can lead to mold and mildew problems and rotting wooden framing.

3)      Water can also enter through cracked or missing mortar and bricks. Remember that bathtub? A lot of water can get through a small hole and it doesn’t just rely on gravity to get there, strong winds can blow rain sideways. That is why tuck pointing (the process of removing and replacing old, failing mortar to weatherize a structure) is such an important maintenance step to keeping your home dry. Once water gets into masonry walls it absorbs into brick and mortar leading to more cracks holes and broken bricks… and more water coming in.

4)      Porous masonry materials act as a sponge drawing water into your home. Poured concrete is notorious for letting water in, especially in poorly homogenized areas where you can see a lot of rock and gravel. It is not unheard of for streams of water to run from such spots. Concrete Masonry Units (C.M.U.) or as I like to call them “concrete blocks” also absorb water. While mortar joints have the same problem it is not an issue if they are in good repair and properly struck. Mortar joints are struck (shaped) in a generally concave manner so they are not directly exposed to rain. Because concrete absorbs water it is important to waterproof it using sealers and other means.

Stay dry.

Water can be dangerous – treat the cause not the symptom or pay thousands of dollars!

Masonry walls can be very beautiful and last hundreds if not thousands of years if maintained correctly. This is exactly our problem, they are not maintained! We live in a state where rain is a norm. Water loves to find its way into things and often cause us problems. Nonetheless, water is not the problem, we are. For many of years I have blamed water as the cause of deterioration of many beautiful historical masonry buildings. Water causing flooded basements, dismounted bricks, collapsed walls and ceilings, efflorescence, and many other pricey issues to fix. Although water might have seemed to be the cause, it was actually just a symptom of a bigger cause: decline and neglect by the owner. So many cases I have seen where the owner noticed a problem but decided to dismiss it. If this is neglect due to lack of money, knowledge, or simply disregard for the life of the masonry structure; the problem will not fix itself unless something is done. Make it a habit to fix these issues before water becomes your issue. Trust me, once water becomes your problem it WILL cost thousands of dollars to fix! Waterproofing is the best method of extending the life of your masonry structure. Flashing, tuck pointing, water barriers- can all be applied to shed water. Take a look at your structure and see what is missing BEFORE problems occur. If your masonry wall has a few dislodged bricks or crumbling mortar, take care of these issues before water makes its way. Remember, structures that seem to be cover from the rain often are not. Wind driven rains have a tendency to find their way into places where it seems impossible. For older masonry structures that seem too old to fix, tuck pointing is probably your solution. Tuck pointing can make your masonry structure look like new construction. Renovation is also quicker and way cheaper than if you were to replace a masonry structure.

Things to look for when examining your masonry structure:

Missing joints or seams,

Crumbling bricks or mortar,

Dislodged or missing bricks,

Missing or incorrectly installed flashing,

Lifting or missing silicon or caulking,

Improperly installed gutters or downspouts,

Mold and mildew,

Constant wet spots,

Large amounts of efflorescence (white powdery substance on bricks),

High ground level (pulling moisture from soil),

Improper slope,

Damage of any sort to the masonry structure.

If you notice these or any other issues when examining your masonry structure it is best to fix them immediately. If you can not do it on your own, call a masonry specialist for an inspection and estimate. You can visit our website at brickmaster.biz and fill out our free inspection and estimate form and a specialist will contact you promptly to schedule a time to meet. Hope this information was helpful and remember: Water problems are only symptoms to your own neglect. Good luck.