Biocide roof clean

[Gordon roof]

Had a biocide roof clean done by a local contractor around four months ago, and had a few problems since. He done the job with spraying method.

The lead started streaking down the slates within a month, and now our slates have started rusting/have rusty spots all over.

The house is only five years old, and had no problems prior apart from some algae.

He is not answering any calls, and has since moved away from the area. Are our slates ruined?

 

[The Makie]

Had a biocide roof clean done by a local contractor around four months ago, and had a few problems since. He done the job with spraying method.

The lead started streaking down the slates within a month, and now our slates have started rusting/have rusty spots all over.

The house is only five years old, and had no problems prior apart from some algae.

He is not answering any calls, and has since moved away from the area. Are our slates ruined?

Your slates are fine, they are just a cheaper quality slate. The rust will happen now, nothing you can do except replace them.

The lead is an issue, whatever they have used is reacting with it badly.

 

[JohnD]

Lead should be cleaned and treated with patinating oil

Probably the sprayer washed off the original oil

 

[datarebal]

Cheap slate, rusting pyrites..
Lead run off maybe it was not oiled after fitting .

Fyi the rusting will get worse and eventually form holes.
The slating is pretty rubbish too , and slate missing next to dormer

 

[Gordon roof]

Can I put a sealer on to stop the water penetrating the slate?

 

[datarebal]

unfortunately not. this might help understand, http://www.sigaslate.co.uk/knowledg...ation-natural-slate-avoid-rusting-slate-roof/

interesting to see rubbish workmanship on these roofs too. obviously the roofer was not informed.