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The Technical Corner; Will it ever stop raining?

It's common knowledge that builders hate the rain, but it's not just that it can stop us working (it has to be a real monsoon for that!) it's also due to the affect it has on buildings themselves. We have seen a huge spike in water ingress jobs and not just roof leaks, this year we have seen a huge rise in wall leaks. The trouble for buildings is they rely on a mix of wet and dry weather to maintain their health, much like their owners who may be partial to a break in warmer climes, buildings also don't cope well with relentless wet conditions. Take a normal brick wall for example. Most properties built after around 1910 will have a cavity wall comprising of two skins (sometimes called leafs) with a gap (cavity) between. This keeps your home dry as the outer wall gets wet whilst the gap allows the inner wall to stay dry. This construction method has barely changed in nearly a century; the cavity has got wider and is now insulated but the principle is still the same. So what's the problem? Well, water often gets through the outer leaf for a range of reasons from poor pointing or render to bad detailing around windows and doors. However, when we have consistent wet weather like we had in December and early January, the outer leaf becomes fully saturated for prolonged periods without any sunny, windy days that help it to dry. This means that without any major defects the wall can still allow a reasonably large amount of water into the cavity. In the most part this will drain out, but what we are finding at the moment is that window trays are failing that might have otherwise not been relied upon in years. A window tray is a lead (or sometimes plastic) liner that sits over any external doors and windows acting like a bridge to the cavity wall, thus when any water gets into the cavity it is pushed back towards the outside wall and not against the inside wall where you would start to see a leak. The issue is that these trays are actually rarely relied upon but this prolonged wet weather means little hidden bits of lead, sometimes nearly one hundred years old are the only thing between your wall and a dry house! How will you know you have this problem? Look at the areas above your windows and doors, especially if you have bay windows or a conservatory/extension. These areas should all have trays above them and this weather will have really tested them. If you are worried about any leaks at all, give us a call for a free survey.

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