Rising damp?

iamlucky18

Hi guys. I think I have an issue.

I didn't notice it before, the internal wall of our living room (underneath the bay window) has very slight light and dark patches of magnolia paint. If you look at it straight on, you won't notice it, but from the side you can.

I have some pictures, but as a new user I can't post them unfortunately.

The paint is on plaster, I think. I'm not a good diyer or have good knowledge on buildings.

The paint is slightly rough in some spots but there is no significant blistering.

The difference in color doesn't have a particular pattern. I would have thought that the wall would have a tidal pattern and a distinctive orange hue around the edges. From what I can tell, there is no rot on the skirting board or underneath the window cill.

So, is this rising damp. If not, what could it be?

Thanks in advance.

firefox1956

Could be that you are seeing some patching of the plaster through the paint ??
Has the bay window been replaced at any time ??

cyclonebri1

It is highly unlikely that it will be rising damp.

My guess;

Your windows have been replaced before you bought the property.
Some tw!t! in the building team has poured crap into the cavity, thus penetrating damp.

Please discuss

iamlucky18

As far as I can see, the bay Windows have not been replaced recently. They're not double glazed, don't seem to have air gaps between the panes and there are black mastic seals on the inside as well around the outside edges. You can also tell the age by the shoddy handles.

The previous owner had got insulation done as you can tell from the blocked off air vents (we're having to get dry rot treated in the lobby area at the mo) and I saw some pale yellow insulation on some of the bricks after lifting up a section of floor board.

So there must be insulation. I don't think there is DPC around the bay because you can see growth in the mortar on the outside. Somebody did a shoddy job of pointing it as the new mortar is falling out. The growth is up to the window, but not all around the bay.

cyclonebri1

iamlucky18 wrote: »

As far as I can see, the bay Windows have not been replaced recently. They're not double glazed, don't seem to have air gaps between the panes and there are black mastic seals on the inside as well around the outside edges. You can also tell the age by the shoddy handles.

The previous owner had got insulation done as you can tell from the blocked off air vents (we're having to get dry rot treated in the lobby area at the mo) and I saw some pale yellow insulation on some of the bricks after lifting up a section of floor board.

So there must be insulation. I don't think there is DPC around the bay because you can see growth in the mortar on the outside. Somebody did a shoddy job of pointing it as the new mortar is falling out. The growth is up to the window, but not all around the bay.

I still think the cavity is bridged by rubble or mortar on brick ties.
You need to check the pointing in detail, infact it needs to be redone.
You also need to check all around the bay, water may be running in that way.

It's not difficult these days to find someone with an endoscope that can be inserted through a hole drilled in the pointing, will give a good view of whats happening in the cavity and further down.

iamlucky18

Ok. I'll try get that looked at.

The other thing that I am worried about is dry rot in the living room. The bay has
two air bricks. One has been unblocked (by me), but the other is blocked by the bricks of a porch built by the owner or a shoddy builder. I know for a fact that one section of the room (underneath the floorboards) doesn't have a problem, but the other I'm not so sure (divided by a partition wall) where the air vent is blocked off by the porch's brickwork. Thankfully, there is no growth through/underneath the skirting nor through gaps. There is no damp or musty smell.

So I'm hopeful there is no issue.

cyclonebri1

The air bricks should always be tunneled under the porch to a new vent under the porch, or if the levels are wrong, ie the porch is lower, then double vent in to porch itself.