Mastic removal

[HH @ 24]

I have just removed an old conservatory. Where the roof sat against the wall, underneath the lead flashing was a thick layer of tar-like gluey substance (is this called mastic?) I have scraped most of it away by am left with a thin layer of sticky tar. Does anyone know the best way to remove this? Thank you

 

[housewinnie]

If your not in a rush let it dry and weather for a while as it should become a little more brittle in time.

 

[Cubist]

It's probably one of the forms of 'pitch' often used as water-proofing in variety of settings. Once applied it can be extremely difficult to remove. Don't be tempted to use any kind of solvent as it will make a terrible mess as it will simply wash on the brick-work below. A wire brush will help to remove the residual expanding foam but will have little impact on the pitch. It will peal - with a lot of time - but the only method I can think of that would not produce collateral damage to the surrounding areas would be heat. A blow torch and scraper might work but it would be a slow and painful exercise to clear it all.

This may be one of those instances where a little lateral thinking may be in order - how about finding a solution to turn it into a feature of the building? Lame, I know, but best I can offer in the circumstances.

 

[HH @ 24]

Thank you, yes may need to think outside the box and embrace it as part of the building's history. Hadn't considered that, so thank you for the creative thinking!

 

[RBailey]

I'd be tempted to wait for a COLD winder day and then try with a small triangle carbide scraper to scrape it off. The cold will make it more brittle and hopefully "break off" and not smear.

Cheers,
Richard B.