Heritage Restoration, Inc.

What kind of Basement Do I have?

Basements come in all shapes, sizes, materials, conditions, uses, and most of all, smells. The best health analysis tool is a nose. It may be somewhat unscientific and simple, but it works. I am not a born and bred yankee, but I learned from some of the best darn yankees out there.

Basements are extensions of a foundation; a hole in the ground designed to keep the dirt from falling in. Yet they can become more complex after they are built; the siting, soil, materials, and construction methods all effect performance and health.

The basement’s precursor, the cellar, served a very important historic function, or else why would someone dig a huge hole by hand? These cellars were not meant for utilities, mechanicals, or even (gasp) living. They were damp and cool spaces, perfect for summer cooking, as well as for root and vegetable storage. By the mid 1800’s other functions were introduced like potable water, sewage, and coal storage. By 1900 and beyond, heating systems, hot water, and other utilities were put in the basement. But the modern day expectation is for a basement to behave like the rest of the house. We force it to act like it was not designed to be, sealing airflow, removing moisture, and adding insulation. But is that right and OK? For that, I go back to the nose.

In Rhode Island, we have foundations of every kind: brick, sandstone, granite, marble, the all-encompassing fieldstone, concrete, cinderblock, concrete masonry units (CMU), and everything that can take compression and not rot as quick as wood. While there are many varieties of foundation materials, there are even more factors that dictate the health of the foundation, as well as the space it encloses.

The symbiosis between stone, brick, or rock and mortar is critical. The mortar is the softer, sacrificial part, allowing the harder building material to perform its critical compression job. Water will eat the softer mortar and create leaks. And when that symbiosis is compromised and a harder mortar is installed, the building material becomes the sacrifice and bad things happen. The moral is do right by your building material, and don’t slap just any stucco or mortar on it, especially when it says it will keep water out. The newer, harder stuff will keep water out of itself, and redirect the water to go thought the building material. And stone, brick, and rock “rots” and deteriorates. Not good.

A homogenous concrete pour should be the best and mostly is. But the weak points are in the construction. A bad footing, bad concrete, or a bad seam can wreak perpetual havoc. Movement can be monitored and rectified, but it is a long and arduous process. Stable cracks and holes can be properly dealt with from the inside, but if water wants come in, it will.

The site where the building was built is the first factor of health. Bristol’s soil is perhaps the most challenging around. Bristol’s clay was not an easy place to dig 300 years ago; so many “basements” were shallow. Clay does not allow water to travel vertically but rather horizontally, thus coming right through the rocky foundations. Also, when a basement is dug in clay, it forms a bowl for water to collect, and water forces its way through the weak point: the foundation.

Sandy soil with small rocks is best, like in South Kingstown. Here the water can travel down vertically.

Proclaiming a single treatment is like saying I want a wood floor. There are countless ways to remedy porous, moist basements, but the best treatment is based on analysis. Beware if you call a basement waterproofing company, they will waterproof your basement. A single solution disregards the problem and its source, neglecting to consider new and existing material, sealing it from the inside so the water sits in between layers. At best waterproofing keeps water from showing up inside; at worst it rots your material where you cannot see it.

If the house is less than 60 years old and concrete, you may be OK for basement waterproofing. If you house is older and a stone or brick, you may need to get a variety of opinions. First, a generalist who understands existing, older buildings can help figure out the problem, like fix your gutters and downspouts. A mason can tell you how to treat the material. Then a basement drainage specialist can direct inside water to a sump pump. A dirt floor can be covered with plastic to prevent evaporation. And lastly, buy the right size and quality dehumidifier. A cheap one will not suffice, since it will not remove enough moisture, eat more energy, and die prematurely.

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