Balcony acting as a thermal (cold) bridge?

[garyd001]

Hi All,

I have done a search and can't find anything directly relating to my issue.

I have a second (top) floor 1960's build flat (originally crital windows) and the two walls immediately adjacent to the uPVC balcony doors are suffering from some kind of mould (not black - almost like efflorescence), two to three feet across and no higher than two feet from floor level. This was cleaned, repainted but has eventually reappeared. I purchased the property in 2007 and replastered all the walls. One of these two had a polystyrene barrier plastered in which was removed (seems like a mistake now!).

There are definitely no concealed water pipes in the vicinity and the roof is in good condition.

My uncle knocked a small hole through the left hand internal wall (thin-ish block) to confirm a cavity. The debris was dark grey but didn’t ‘dry’ to a lighter shade so we assumed not overly damp.

The property management board finally(!) sent a surveyor round. He looked at the walls and asked whether we kept anything against them. NO. He shone his torch through the small hole and concluded that it would need a borescope to ascertain whether any moisture was bridging the cavity from the balcony, which admittedly is not in the best cosmetic condition. The pebble dash around the external is in need of replenishment. The floor is sealed with bitumen based paint though has fine undulations and peaks (almost crack-like-but not as far as I can tell).
I have chased and chased the board until I have now received a letter advising it’s thermal bridging and I’m on my own!

Obviously I shall be questioning the diagnosis based on what the surveyor told me. However, in the meantime would anybody be able to advise on a ‘best’ solution.
I do feel that if it is thermal bridging then that should be part of the fabric of the building and should be resolved by the freeholder.

Any advice and comments will be much appreciated.

Many thanks.

Regards,

Gary

 

[AronSearle]

Seems a reasonable conclusion to draw.

I do feel that if it is thermal bridging then that should be part of the fabric of the building and should be resolved by the freeholder.

Not really, as at the time of construction it probably complied with thermal regs, freeholders have no obligation to keep the thermal envelop up to modern regs, it's also not a 'fault' but just a characteristic of typical **** UK housing construction.

Squirty foam around the windows in the cavity will help, which you can do probably do yourself, as will blown cavity insulation *properly* installed. The latter probably needs to be agreed by the freehold management company and fully funded by the leaseholders, (freeholders typically won’t pay a penny for anything they don’t have to).

Someone will also be along shortly to tell you to ventilate more.

P.S. Welcome to the joys of owning a leasehold flat!

 

[jeds]

Very common. I can almost picture the flats, the balcony and the mould. My advice (after you have 100% checked the cavities) is hack the plaster off the external walls and re-board with thermal laminate plasterboard.