Is your house suffering from subsidence? Don’t panic – there are solutions…

Subsidence is the gradual caving in or sinking of an area of land. When a house is built on this land, obvious problems arise. From diagnosing the issue to prescribing the cure, read on to find out about the housing ailment that’s got homeowners cracking up.

Diagnosis
The telltale sign of subsidence is cracking.Diagonal cracks that suddenly emerge on plasterwork inside, and brickwork outside, should wave a warning flag. New home buyers shouldn’t be too concerned about fine cracks in freshly plastered walls though – cracks caused by subsidence are usually wider than the thickness of a 10p coin. Weak points around doors and windows are a hotspot for cracks, with fixtures often sticking due to the distortion of the building.

Cause
Certain soils are more vulnerable to change than others. Clay soils, for example, shrink and swell according to the amount of moisture which is in the ground. Vegetation is also a key culprit, as trees and large plants suck the moisture out of the soil, especially during periods of no rain. Willow trees are the worst offenders, and should be planted at least 40m away from buildings. Oaks, poplars and horse chestnuts also cause drought in the soil, due to their sheer height and the amount of moisture they need. Keep an eye on your drains, too. Damaged pipes can cause leakages that will soften or wash away the ground, destroying your foundations and causing your house to start sinking.

Prescription
Here’s our step-by-step guide to solving subsidence:

1. CRACK THE WHIP: Check your property regularly for cracks. Although you may not be thinking about what’s happening on the outside of your house, it’s just as important as the inside.
2. Survey swot: If you’re buying a property, make sure you get a full survey done of the house and land. If you scrimp on a survey now, you could end up regretting the foundations you chose later. Similarly, if you’re thinking of extending or building a conservatory onto your house, check you’re on solid ground first.
3. Plant safe: When choosing shrubbery for your garden, think about the moisture demands of each plant. Magnolia or yew trees provide an attractive alternative to majestic oaks and willow trees.
4. Fast track: If you’re worried about your home, act quickly. Notify your insurance company so they can get professional surveyors to assess the damage before it gets any worse. 
5. Keep calm: Just because you’ve spotted a few cracks, it doesn’t mean your house is falling down. Subsidence is a common problem and can be dealt with by experts trained in the field. Removing trees can be an efficient solution, while pruning back can help reduce moisture loss in conservation areas that don’t allow this. Be careful, though, as trimming plants can also stimulate their growth and hunger for moisture. Underpinning may be prescribed for extreme cases – this involves stabilising the land with fillers. This may sound like an upheaval but in recent years, experts have developed efficient, less invasive and cheaper methods. 

Photograph: getty images