Apartment insulation, air-tightness issues

[tea drinker]

Hi folks, my apartment has pretty severe air tightness issues, and as a consequence is eating a lot of cash to eat especially these days.
I have wrap around windows on 2 sides, they are close to floor to ceiling but not quite.

There's an exterior wall part above the windows. It's I think somewhere here the air-tightness issue is.
Bedroom 1 - I had a hole beneath one of the windows, it would blow a LOT of cold air into the room anytime there was wind on that side.
Bedroom 2 - The plasterboard moves a little when there's wind on that side, but it's nowhere near as cold as bedroom 1.

Living room - has a false chimney breast where the gas boiler is. I can see up into the roof, see some of the insulation and past it too.
There is an electric heater mounted on the Chimney breast, if there's a strong wind then cold air is ingressing the room from the heater.

How to remedy this?
I guess the whole chimney breast area, needs to be covered over somehow i.e. have it's own "ceiling" ?
The top of the walls where draughts get behind the plasterboard, can that be filled in with foam?
I know foam is usually between blocks but I don't think that's the construction used here

As a side issue I'd like to upgrade to a condensing boiler (no more grants for that ?) but I understand the water condensate from those boiler is acidic and so can't be just dumped to terrace, needs to go to a water drain? Terrace is ~2 metres from this chimney breast.

Apologies for the long winded post, any advice greatly appreciated.
I'm in D18 if that makes any difference for recommending someone.

PS. I might add some photos later to give an idea of the shenanigans

 

[Micks'r]

It looks like you think you know where the issues are but I would still advise having the apartment tested for air tightness. This will allow you to gauge how severe each weakness is and also ensure that you have found them all. It is also very important that the tester has experience in how to remedy the various issues and can give good advise and options to ensure a significant improvement.
To demonstrate what can be achieved, I was recently involved in an apartment reno project where the measured airtightness was improved by close to 80% (from 10 to 2.2 m3/hr/m2@50Pa) by paying attention to detail and carrying out some very simple, inexpensive but very effective measures.

 

[Leo]

I'd suggest talking to other owners in the same development as this is likely a widespread issue that might be cheaper resolved en masse, and then raising through the management company.

Remember you will need management company permission before you go about fixing most causes of these issues as they own the structure.

 

[tea drinker]

Thanks for the replies folks, let me give you a tour of the living room ;-)
Here the "Chimney Breast" in question:

New item by Martin D

photos.app.goo.gl

On the right of that is the inset gas boiler:

New item by Martin D

photos.app.goo.gl

See insulation and attic space above, also missing insulation etc.

New item by Martin D

photos.app.goo.gl

New item by Martin D

photos.app.goo.gl

New item by Martin D

photos.app.goo.gl

You can see the breezy electric heater I mentioned. It's not totally opened, there are some plasterboard internally but there's plenty of large holes punched through for cabling or possibly just the craic.
Here's a view from the recess of the electric heater, looking up (through one of the holes)

New item by Martin D

photos.app.goo.gl

Same deal, gaps in insulation and no actual capping of the internal to prevent air movement.

Now you've got a better picture what do you think for this guys? For me I can easily hit the holes with expanding foam fill the air gaps around the plasterboard etc but sure it's still open at the top, I've practically got an exterior wall in the middle of the living room ;-)
Is that up to spec for 2005... or any year really, is it more an issue for the builder?

 

[Micks'r]

Some interesting pics there!
In my experience, using spray foam in these types of situations is not effective, it is better to use proper airtight tape / membrane depending on hole size etc. (Imo, sprayfoam is a filler, not a sealer)

A key consideration in all of this though is to first determine where / what your air tight barrier is and then figure out how to ensure it is continuous. Concentrating on one area such as the false chimney breast while good in its own right may not yield much results if all you are doing is diverting the air leakage to other areas / weaknesses. This is where, in my experience, the value in the full survey comes into play where all the issues should come to the fore and a plan of action drawn up to tackle them in a methodical manner.

It is also very likely that the same weaknesses are present throughout the development.