Help! Advice on identifying damp source at high up!

[Jackish]

Hi all,

Apologies for this sounding like a silly question but we're first-time homeowners and have noted that one wall of a room in the loft conversion has random damp patches (kind of yellowish). Tapping around the wall, we can hear some parts are more hollow-sounding. Suspicion is that it is penetrating damp..?

The issue is identifying the source. This wall is next to an external wall and looks like it could be a roof, brick or some kind of leakage from the outside. However, it's far too high up for us to get a ladder to investigate, plus being newbies we don't know what to look for.

In this case, who should we get in to have a look without being charged a fortune? Damp proofing company? Damp surveyor? Roofer? Help! In the London area.


Thanks,
Jackish

 

[mointainwalker]

Do you know if there is a chimney there ? What is the wall made of ?

 

[Jackish]

Do you know if there is a chimney there ? What is the wall made of ?

Hiya, think it's a standard wall - bricks and plaster on the inside. No cavity I believe. Edwardian property from 1900s in London, in case that reveals anything useful about construction from the time.. Oh, and no chimney on that side of the house. Chimneys on the opposite side only.

 

[^woody^]

Stains in the ceiling of a loft conversion is most likely a roof leak somewhere, so you need a roofer

 

[tim00]

1. Was the loft conversion there when you bought the house? Any documentation or drawings?

2. Does the wall in question have a roof dividing parapet from your neighbour's, or is this a gable wall?

3.If you are newbies to this game then dont go up ladders or on the roof. Get some bino's and stand back and view the roof from various angles.

4. As has been said above, it's typically a roofing matter.Dont go near any damp companies. Roof leaks are notorious for starting in one place and showing up in another.

5. The hollow sound you hear is due to plaster board dry lining, and perfectly normal.

 

[Jackish]

1. Was the loft conversion there when you bought the house? Any documentation or drawings?

2. Does the wall in question have a roof dividing parapet from your neighbour's, or is this a gable wall?

3.If you are newbies to this game then dont go up ladders or on the roof. Get some bino's and stand back and view the roof from various angles.

4. As has been said above, it's typically a roofing matter.Dont go near any damp companies. Roof leaks are notorious for starting in one place and showing up in another.

5. The hollow sound you hear is due to plaster board dry lining, and perfectly normal.

Thanks for your thoughts, tim00. The loft conversion was done some 20 years ago so not a whole lot of documentation available. The wall is a gable wall. Like you, we suspect the damp is a result of water ingress originating from somewhere along the roof but having tried to take a good look by sticking our heads out of the skylight window and using a good dSLR camera to take hi-res shots, we found nothing. Essentially, we think a proper physical poke about is required but of course we don't have a ladder that high nor the guts to climb up on the roof since we don't know what exactly to look for (photos showed up nothing 'obvious' to the untrained eye). The patches of damp on the wall sound hollow when knocked on, whereas the dry areas of the same wall are solid sounding, so we know that at least isn't right.

Taking your advice to steer clear of damp proofing co.s and started contacting building contractors to see if any can come to take a look and provide some thoughts and quotes. Cheers!

 

[tim00]

Thanks for your reply. Go below the gable and with bino's if possible examine the barge board, and the edge/verge detailing - is it pointed-up or does it have a custom dry-verge detailing? what material is the roof cover eg slate or conc. tile?

What type of "skylight" do you have? Put your head out and examine how the skylight is flashed.

Can you post pics?