How to tell a drainage problem from a masonry problem

When something built out of stone, brick or block starts to look wrong, the stonework gets the blame. It is the visible part, so it is the part people photograph and point at. But in most of the jobs we are called to assess in Bergen and Hudson Counties, the masonry is reporting a problem rather than causing one, and the problem is water.

Retaining walls: holding back soil means holding back water

A retaining wall is not really holding back soil. It is holding back soil plus whatever water is in that soil, and water is heavy. When rain saturates the ground behind a wall, the pressure on the back of that wall rises sharply. If there is nowhere for the water to escape, the pressure keeps building until something gives.

The classic symptom is a wall that has bellied outward in the middle while the ends stay put, because the middle is the least restrained part. Another is a wall that leans progressively rather than suddenly. Neither of those is a sign that the units or the stone were poor. They are a sign that there was no drainage behind the wall, or that the drainage that existed has silted up.

A wall built properly has clean drainage stone against its back face, a filter fabric between that stone and the soil so fines cannot migrate into it and blind it, and weep holes or a drain that actually discharges somewhere. If you have a wall with weep holes that never run after heavy rain, that is not a good sign. It usually means they are blocked, not that the ground behind is dry.

White bloom on new masonry is usually not a defect

A powdery white deposit on new stone or brick worries people more than almost anything else. It is called efflorescence, and it is salts within the masonry being carried to the surface by moisture and left behind as the water evaporates. On new work it is common, it is cosmetic, and it generally weathers off over the first year or two.

What is worth attention is efflorescence that keeps returning heavily, year after year, in the same place. That suggests water is moving through the masonry continuously rather than simply drying out after construction, which points back at drainage again. Whatever you do, do not attack it with acid. Acid etches the surface of the stone permanently and you will be looking at that damage long after the bloom would have gone on its own.

Patios and walkways: the fall was set, or it was not

A patio that has one rocking flag has a base problem in that spot. A patio where water stands in a puddle after every shower has a fall problem across the whole area, and that decision was made before any stone was laid. It is very difficult to correct afterwards without taking the surface up, which is why it is worth asking about at the quoting stage rather than the snagging stage.

The fall needed is small. It is not something anyone should be able to see or feel underfoot. But it has to be there and it has to run somewhere sensible, away from the building rather than toward it.

A simple diagnostic you can do yourself

• Go outside during heavy rain rather than after it, and watch where water actually travels
• Check whether downpipes discharge away from walls and paving, or straight down beside them
• Look for weep holes at the base of any retaining wall and see whether they are running
• Note whether damp patches on a wall are highest near the ground or spread evenly
• Check whether garden beds or gravel have crept up above damp proof level against a wall

That last one catches a surprising number of problems. Ground levels rise over the years as mulch and topsoil are added, and eventually the outside ground sits higher than it was designed to, giving water a route it never used to have.

Why the distinction changes the job

If the masonry genuinely failed, the fix is masonry. If water caused it, then rebuilding the masonry without addressing the water rebuilds the same failure with newer materials. That is the single most common way people end up paying for the same wall twice.

It also changes the cost in both directions. Sometimes a drainage correction is much cheaper than the rebuild the homeowner was braced for. Sometimes it means a job that looked like repointing is really an excavation job behind the wall. Neither is good news or bad news until somebody has looked properly.

Because we run our own excavation and site work alongside the masonry, we can look at both halves of that question at once. Call (201) 945-0064 with the address and describe what you are seeing.