I've recently moved in to a house with cavity walls. I've noticed that the internal faces of the walls are freezing cold in the mornings, so I started wondering if cavity wall insulation would be a good idea.
Looking carefully at the outside however, I could see what looked like the pattern of filled holes to indicate it had already been done. I then noticed that along with a few airbricks through to the house, there were a couple of strange 'extra' ventilation points on the outside that didn't correspond with anything on the inside...
One at a low level on the side wall looks like an old flue from a boiler (presumably at one stage there was a floor mounted boiler) - I can't see much more on this without taking it off the wall, so I don't know if the hole has been filled etc. The house side is behind wooden tongue&groove boarding in the hall. I know it is definitely redundant, as there is a separate flue for the current boiler, located directly through the wall from where the boiler is mounted in the kitchen.
The other one is located on the wall outside the front door, and is just a plastic ventilation cover. I shined a torch through this (will look properly in the daylight as well tomorrow), and could see in to the cavity, where I could see what appears to be some form of insulation, and then the inner wall. Feeling closely on the inside of the house, it appears that there must at one stage have been a full vent, which has then been filled in on the inside. My question is, should the outside hole have been filled as well (and should I arrange filling it), as I was under the impression that a cavity wall was designed to prevent air circulation, so surely having a vent that is venting the cavity will be encouraging it?
Looking carefully at the outside however, I could see what looked like the pattern of filled holes to indicate it had already been done. I then noticed that along with a few airbricks through to the house, there were a couple of strange 'extra' ventilation points on the outside that didn't correspond with anything on the inside...
One at a low level on the side wall looks like an old flue from a boiler (presumably at one stage there was a floor mounted boiler) - I can't see much more on this without taking it off the wall, so I don't know if the hole has been filled etc. The house side is behind wooden tongue&groove boarding in the hall. I know it is definitely redundant, as there is a separate flue for the current boiler, located directly through the wall from where the boiler is mounted in the kitchen.
The other one is located on the wall outside the front door, and is just a plastic ventilation cover. I shined a torch through this (will look properly in the daylight as well tomorrow), and could see in to the cavity, where I could see what appears to be some form of insulation, and then the inner wall. Feeling closely on the inside of the house, it appears that there must at one stage have been a full vent, which has then been filled in on the inside. My question is, should the outside hole have been filled as well (and should I arrange filling it), as I was under the impression that a cavity wall was designed to prevent air circulation, so surely having a vent that is venting the cavity will be encouraging it?
