Are you worried about cracks in your old house’s wall? It is essential for preserving any place, but mainly a period home, to spot the signs of structural issues.
These are just some of the things that can lead to structural problems: overgrown trees and shrubs, cracked drains, leaking rainwater products, missing roof tiles. If left unchecked, this will entail expensive repairs and could even cause structural problems such as subsidence and movement that sound more frightening.
Prevention is crucial, so you need to stay on top of external maintenance (use our guide to find out how), but when you think the harm can already be done, there will almost always be a solution for structural issues.
WHY MIGHT YOUR HOUSE HAVE STRUCTURAL PROBLEMS?
While a degree of movement in an old house is unavoidable, cracks should not overlook in the plasterwork or brickwork, and the maintenance problems that cause them should not be either. Even so, it is worth noting that traditional buildings were designed using lime and other materials, allowing the structure to be modified somewhat.
Other reasons for movement may be that a structural feature has failed or alterations have been undertaken that have been improperly considered. Due to insufficient help during the work, this may have undermined the system or placed loading or tension where none was present before.
It should also remember old mine operations and springs. If in any doubt, seek advice from a structural engineer specialising in buildings of the same age and type as yours.
Where serious problems are evident, it may be necessary to temporarily prop the building, but this should be done by experts.
HOW TO SPOT STRUCTURAL PROBLEMS
- Cracks and bulges appearing in walls both internally and externally. In new work cracks may occur due to shrinkage during drying; they are common after central heating has first been installed.
- Doors and windows that bind can indicate structural movement but the problem may be due to damp weather.
- Tapered cracks running diagonally from the corner of doors or windows. Movement tends to show here – as openings in walls are weak points.
- Cracked render or plaster around the top of a window might mean that the bearing end of a timber lintel is rotten.
- Cracks between a bay window and the building indicate that the bay window isn’t tied correctly to the structure.
- Sloping floors could point to subsidence or other structural problems.
CRACKS AND BULGES IN WALLS
Suppose structural problems are suspected, and a hairline crack is visible. In that case, it is essential to track the issue over time to determine its severity and determine whether the movement is ‘live’.
If the crack continues to expand, place a pencil mark at the point where the trial ends, date it and repeat the process regularly. Check if, with the seasons, the crack opens and closes. Take notice that an expert should often examine larger cracks of 5 mm or wider.
Look for signs that may mean it is benign before worrying. For instance, finding cracks that have been repointed, but have not opened up again, is comforting, as this is a sign that movement has stopped.
They have settled into their new place in several instances, despite doors, windows or floors being at odd angles. It is probably safe to say the issue has resolved if there is no sign of new movement.
Spreader plates can be visible on specific structures. These were commonly retrospectively fitted to restrain a bulging wall. Although they have probably resolved the problem it is worth periodically checking that nothing is untoward.
*contoh gambar*On many old buildings ‘spreader plates’ will be visible. These were usually fitted retrospectively to restrain a bulging wall
STRUCTURAL PROBLEMS RESULTING FROM DAMP
Due to rot, several structural issues arise. It will undermine roof rafters, lintels above doors and windows, floor joists, or even the actual structure of a timber-framed house, so it is crucial to deal with damp issues before becoming serious.
Means replacing missing tiles or slates, repairing and clearing gutters and downpipes, and generally looking for areas where moisture may penetrate and cause damage to the building’s structural elements.
Another source of harm to walls caused by water is iron corrosion. ‘Ashlar’ or smoothly cut stone cladding was often secured with iron ‘cramps’ or links on the exterior face. When the water reaches the wall, it rusts and expands, creating structural issues.
Other iron fixings embedded in a building’s structure are equally vulnerable, so should periodically be checked for signs of trouble.
HOW SHRUBS AND TREES CAUSE STRUCTURAL PROBLEMS
One of the most frequent causes of structural problems is shrubs and trees. Their roots can damage drains or suck moisture from the soil, and this can cause downward movement or subsidence of the ground supporting the building, especially in clay areas.
It is beneficial to prune both their crown and roots as this decreases the amount of moisture taken from the soil.
It is not always a good idea to cut down a tree as this could mean that the land becomes waterlogged, and the roots no longer retain water. This, in turn, results in soil expansion and an upward movement or heave that can damage a building as much as subsidence.
*contoh image* Ivy and other climbing plants might add character to a house but, over time, they can destabilise walls
HOW CLIMBING PLANTS CAN DESTABILISE WALLS
Climbing plants should be overseen. In particular, Ivy can destabilise walls as its roots find their way into cracks and crevices, particularly where pointing is flawed, and they push the masonry apart as the tendrils grow and spread.
Established plants should be cut off and poisoned close to the root. Then, once the vegetation has died, it can be removed carefully.
*contoh gmbr* Subsidence and structural movement can cause door and window frames to sag
HOW TO FIX YOUR HOME’S STRUCTURAL PROBLEMS
Where structural problems are suspected, you should inform your insurance company who will investigate further. Generally, the homeowner has to pay the first £1,000 of any claim. Your insurance premium is likely to increase, and it may be not easy to move to a new insurer in the future.
If subsidence or heave is suspected, trial trenches will probably be dug and root and soil testing undertaken. Nearby drains and pipes will also be investigated to ensure they are not leaking or blocked.
Dealing with damaged drains or invasive trees or shrubs is often the solution, but underpinning might be recommended. This is an expensive and disruptive process and, unless the whole building is underpinned, there is the danger that it will impose rigidity on a localised area.
This could potentially cause differential movement between the now solid section of the building and other more flexible parts to which it is attached, thus resulting in further problems.
When structural damage has occurred, always try to retain the structure’s integrity through careful repairs rather than rebuilding. If walls have cracked and repairs are necessary, traditional lime mortars, renders and plasters should be used to allow breathability and a degree of movement.