Testing Your Brick Structure

Bricks

Bricks

One of my favorite Sunday activities is to take a drive with my wife around neighboring communities. Having worked in construction management for years and now in real estate, it’s interesting to converse with her about the market, design trends and current conditions that affect both my job and our home.

On a recent trip through southern Vermont, we stopped on a quaint street lined with brick houses (beautiful examples of masonry). It had been a particularly blustery day and my wife asked me: What’s that white coating on the side of the building? Is it frost? Clinging snow? Some kind of damage?

Hoping that she was ready for a 30-minute explanation, I launched into my speech about masonry and the power of water:

When a masonry structure in moderately good condition suddenly develops a white substance, or even a crust, you have an indicator that moisture is moving through its surfaces. The white material could be free lime or latent salts deposited as efflorescence on the bricks’ exterior.

Unless a building comes with its own umbrella, it’s going to get wet, which leads to ill effects over time. This moisture can damage the interior of your building or cause odors, amplified freeze-thaw processes, rot, mold and corrosion.

The water is carried by capillary conduction (suction) through the bricks’ interconnected pores, usually between the brick and mortar and through cracks in the mortar or masonry units (vertically, from the ground or leaky gutters, and horizontally, from driving rain).

To determine how much moisture is moving through the edifice, and to help you choose the correct waterproofing material, a certified architect or engineer can perform a RILEM test.

After a visual inspection (feeling, listening and smelling the affected area), the RILEM test will help a professional evaluate the structure’s resistance to wind-driven rain (up to 120 mph), points of entry and the rate of entry - a quantifiable look at the speed of moisture passing through the brick construction.

The RILEM tube/test looks like a small top hat with a long cylinder protruding upward; it’s placed with the hat-like opening against the surface of the masonry wall at the joints. The shaft is marked with measuring units that an expert will use to fill the apparatus with water and gauge the rate of absorption at different points along the wall.

Starting with a baseline and/or unweathered areas should give the technician an idea as to whether the amount of damage needs treatment and if one area is more vulnerable than another. For example, areas having an absorption rate of 5 mL of water in five minutes or less are more likely to leak during wind-blown rain. An absorption result of 5 mL in 15 to 25 minutes is less in danger. If your weathered area absorbs water twice as readily as an unweathered section, then weathering, and weatherproofing, should be a concern, given all other factors are equal.

The RILEM test will also help a professional try different products on the exposed section(s) of your masonry to see which one is best suited to your situation; comparing the rates at which the water is absorbed at different sites will gauge the relative degree of protection afforded by a water-repellent treatment or sealer.

The results of this test will hopefully confirm any initial suspicions, eliminate other possibilities, both in damaging agents and repair options, and provide a baseline for the structure in the future.

When real estate is one of your most expensive investments, you shouldn’t leave anything to chance. It’s important to consult an expert as soon as you notice problems or changes with your home and about the best preventative and treatment options for long-term success.

This article was also published in the Stowe Reporter.