Condensation has to be one of the biggest causes of damp in a property especially during the colder months of the year. This is often mis-diagnosed by un-qualified surveyors or rogue surveyors trying to push a damp proof course. To determine condensation on our survey we use thermal imaging cameras, hygrometers, infrared laser point measuring kit and our eyes. The great thing about using a thermal imaging camera is the customer can actually see the problem area with their own eyes on the screen so they know exactly what the problem is and the cure can be explained.
This is another common problem…..bridging render. As you can see the render is bridging the concrete path, which is potentially bridging the damp proof course causing dampness to rise up the wall. The cure is to lower the ground level 150mm below the damp proof course, and make sure the damp proof course isn’t bridged.
Wet cavity wall insulation, because of the terrible weather we have had lately with horizontal winds continually driving the rain into the wall, we have noticed a considerable increase in this problem. Penetrating damp is a very common problem that is also often mis-diagnosed as rising damp. We use thermal imaging cameras to locate where the dampness has entered through the fabric of the building.
The red circled area shows the remedial damp proof course that was never needed, look at the arrows showing the bridging render. The wall is still damp after the installation of the remedial damp proof course and this is because the bridging render wasn’t removed….
Can you drill a remedial damp proof course behind a bridging plinth and expect it to work, the answer is a big fat NO. Why did they do this? Either they don’t know as their not qualified members of the Property Care Association, or they simply don’t care about bodging up the work.
And again, if you live in an old house when you pop out next in your street have a look at your neighbours house, I bet you one of your neighbours houses will look like this.
Hopefully you now know what the problem is here…..
This picture is typical of a cowboy damp proofer that has under priced the job to get it and cut every corner possible!!! I was called to this property in Trowbridge Wiltshire to have a look at why the ground floor walls were still damp and the floor was rotting, the house still had 18 years left on the damp and timber treatment guarantee. Obviously the contractor wouldn’t go back and fix the problem and the guarantee was Mickey Mouse! The cause of the damp was never rectified in the first case, the problem was being caused by sub floor condensation, basically the sub floor ventilation needed to be increased, which is done by adding additional air bricks. But when you add air bricks most people actually take a brick out to increase the sub floor ventilation but not their damp proofer, he just drilled some holes and screwed a new grill on and jumped on his horse.
We all know gutters should discharge to a drain…… how often do I see this? Everyday, of course this is going to cause a damp problem to the ground floor walls. Make sure gutters discharge to a drain or a soak way.
This is a picture of a broken down damp proof course, it does happen but very rarely though.
This is my favourite picture of them all, this is just unbelievable, the reason this is in here is because every time these are installed the walls stay damp, because the re-plastering is never done. This so called damp proofing system is supposed to go on the external walls….well look closely this is on an internal wall, they told the old lady that because you have your back door open for your dog it will work!!! This product is marketed by saying that there is no mess as no re-plastering is necessary blah blah blah and the when it fails they can be taken to court for misrepresentation. So if you are on of the unlucky ones make sure you contact Graham Coleman
Have a look at our main website for further reading or to book a survey www.completepreservation.co.uk