The last six months of 2020 seem to have gone by in a blur as a result of the restrictions and complications of COVID-19. This really hit us all on 23rd March 2020, when the country was put into lockdown, which, because it went through the whole of spring and parts of the summer in 2020. We all experienced some lovely dry, sunny weather for long periods of that time.
However, with the colder temperatures and very wet weather over the past week, it has seemed like we’ve leap-frogged from the end of last winter to the start of this autumn and winter.
This seemed like a good time for a reminder to check around your property externally, to make sure it is water-tight from the outside before winter really sets in.
This was brought to mind over the last few days when after seeing water pouring over the edge of a gutter onto a flat roof (see picture below), which is a recipe for all kinds of problems.
The problem here is that the gutter looks like it has become twisted and water is simply cascading off the roof behind the gutter and running down onto a flat roof covering. This is something you would not necessarily notice unless it is pouring with rain.
You will notice some tall deciduous trees nearby which means the gutter may also be blocked with leaves from last winter. There is also a cable, which seems to have been taken up into the gutter, which will also block the flow of water draining properly from the gutter. If this were left un-checked for a long period of time, it is possible that water could penetrate the flat roof covering, leading to fungal decay in concealed roof timbers and the splashback from the water hitting the roof is likely to soak the house wall.
Here are a number of items it would be very sensible for you, the property owner, to check over the coming weeks to make sure water does not penetrate into the building’s fabric. The best time to have a walk around your property and check some of these things is when it is pouring with rain.
Rainwater goods – gutters, downpipes, hoppers etc.
Water could be leaking from gutters as a result of defects in the joints between gutters, blockages in the gutters (leaves, moss etc.), poorly fittings gutters and twists in, or misshapen gutters. Down-pipes could be leaking around joints and if joints have become detached. Hoppers could be over-flowing if they are blocked at the top or, if too many pipes go into one hopper.
Drain gulleys
At ground level, make sure the drain gulleys are clear of leaves and other debris which will prevent water getting into the drain system. Make sure the surrounds to the drain gulleys are in a good condition and not broken.
Pointing between bricks and low level rendered plinths
If pointing between bricks is missing, have it repaired because the underlying mortar course is more absorbent and water will penetrate this far easier where pointing is loose or missing. Where there is a low level rendered plinth, check it is not cracked or blown, because water ingress can occur and it will be trapped behind the plinth. This can also lead to “bridging” of the damp proof course.
External render coatings
Make sure the render is in a good condition and has not blown (from the substrate) or cracked. As stated above, water will end up being trapped behind the render and will penetrate the wall substrate.
Brick surfaces at low level
Check for “spalling” of bricks, which usually occurs more in Victorian properties, which have been built in traditional London stock bricks. This tends to occur when the bricks have absorbed water, which then expands when it has become frozen during winter months. The external face of the bricks is then forced off, which leaves a much softer and absorbent exposed surface.
Check for “spalling” of bricks. When the bricks have absorbed water, the external face of the bricks can be forced off, which leaves a much softer and absorbent exposed surface.
External decorative finishes
Have a look at door and window frames, fascia boards, soffits and painted bricks / render. If the paint is flaking, water ingress could occur.
Roof coverings
Have a look at flat roof coverings, tiled roofs, parapet flashings, valley flashings, the flaunching around the top of chimney stacks etc. Make sure they all appear in good order and if not, enlist a reputable roofing contractor to inspect, as these are often the areas a property owner cannot get to.
Ground levels against the house walls
Have flower beds been built up around the property and are they now higher than the line of the damp proof course? It is usually possible to work out which course is the damp proof course (DPC) because it tends to be a wider mortar course than the others. When the property was built, the damp proof course would have been at least 150mm above the external finished ground level and below the line of the internal floor levels. Trouble is, over the years, external ground levels get built up as a result of flower beds, path levels, decking etc. All of which can result in the DPC becoming “bridged”. If the issue is a flower bed, this can often be lowered to expose the DPC level but it may not be as simple where paths have been laid.
Hopefully, this gives a bit of an insight into what you should be looking for. If we may be of assistance, please do contact us on 01276 66466, or email on info@preservationtreatments.co.uk
