Any property can suffer from damp problems depending on the moisture content within the rooms. Excess moisture in any room can cause mould, wet rot/dry rot, or rising damp. But structures with rooms or spaces below ground level are at greater risk of water ingress, leading to severe damp problems and even structural damage.
Basements and cellars were once a common feature in years gone by when coal was the main fuel, and basement flats were often built in places where land prices were more expensive. They were made purposely to be cool so that certain foods could be stored in a time before refrigerators and modern preservatives. Many people had a 'root cellar' which was essentially a deep hole in the ground to store root vegetables over winter.
These days, many people are renovating old basements and cellars to use as extra living or storage space. Even some new builds are going underground, either to maximise space or in keeping with eco-living projects that use an earth bank for thermal mass.
All buildings have some moisture content, whether left over from the construction process, through the use of the rooms or simply through the everyday processes of living. On floors at ground level or above, we can regulate this more easily with effective ventilation. It could even be as simple as opening a window.
Clearly, this isn't an option below ground. Then there's the water table to consider. This is the natural level at which ground water sits within the local area. You may have come across this when digging a deep hole as water starts to accumulate, which means that you're probably in an area with a high water table.
When the earth surrounding a property becomes saturated, either because of a high water table, excessive rainfall, leaking downpipes and so on, hydrostatic pressure can force water through cracks in the basement wall (or foundation wall).
Older buildings with brick-lined walls allow moisture ingress through the lime mortar, which often carries salts (efflorescence) that accumulates in white deposits. Mildew and mould growth can blight the walls, and the surface of the bricks begins to crumble.
Also, a change in the ground surface or water table around an old building can have a dramatic effect, as can blocked or broken drains. Leaking pipes (especially sewage conduits!) can be a significant cause of damp within basements.
The main aim is to stop the ingress of water so that the humidity and moisture content can be properly regulated. Keep in mind that you are not trying to dry it out completely as this would result in an uncomfortable environment.
First, the cause of the problem needs to be correctly identified. Is it a fluctuating water table? Has hydrostatic water pressure pushed water through porous materials and into the basement? Are there leaks or visible cracks in the walls? Damp Hero are qualified damp-proofing surveyors and will be able to determine this and recommend an effective course of waterproofing.
There are a few different types of basement waterproofing options, each one depending on the use of the space, the age of the building and construction materials, the extent of damage, and the level of access to external walls (for example, in urban settings with a footpath directly outside, or if the property is within a row of terraced houses). There isn't a single solution that fits all cases, and each building is assessed individually for the best approach.
The most commonly used method these days is the Cavity Drain System, which is a water management system. Instead of stopping liquid water penetration, this method uses a series of wall membranes, drainage channels and sump pumps that allows water to be collected and directed away from the property. Natural drainage will be used if possible, but if not then a pump will be used to take the water away. This method is an excellent way to transform basement flats and musty old cellars into beautiful, dry, modern spaces!
Alternatively, a tanking system will be used. This can be either a cementitious solution that involves the foundation walls being coated in a waterproof slurry, or a waterproof membrane (often referred to as barrier protection). Sometimes, a combination of tanking and water management is recommended to provide the best protection in cases where the basement construction materials are very porous and the flow of water may be too great for the Cavity Drain System to cope with.
It's true that some of these methods can involve significant cost, and there may be disruption to your daily life for a few days in some cases, depending on the level of work involved (particularly if external excavation has to take place for things like perimeter drainage channels).
However, when weighed against the potential for improving your home or business premises, adding extra space that is clean, dry and usable as well as adding value to the property, then the benefits far outweigh any negatives. Just imagine, that musty, drab, neglected and unusable basement could provide a much-needed storage area, a playroom, an office, an extra bedroom - the possibilities are almost endless!
Besides all this, ignoring a damp cellar or damp basement won't make it go away. The problem can and will only become worse over time, potentially leading to major structural damage that will incur even more cost.
Whether you are planning a basement conversion, a new build with underground levels, or simply want to resolve a damp problem that is damaging your property (and possibly your health!), then you should contact Damp Hero a specialist basement waterproofing company without delay.
Damp Hero will provide you with all the information and advice you need, will carry out an extensive survey of the property, and install the most effective and efficient method of waterproofing to suit your requirements.