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Tar stains onyboat

We're getting tar streaks on the side of the boat from the stove chimney. Three things; what causes it, how can I prevent it happening, how can I clean the stains off ( nothings worked so far!).

Asked by: Paul Taylor  | 5.32pm, Tuesday 28 March


WW says:

It is usually caused by the smoke and fumes from the fire condensing on the cooler upper parts of the flue/chimney and running down the side. If the chimney is the single skin type, this means that it soon gets onto the roof.
This problem can be cured - or at least minimised - by fitting a double skin chimney in which the inner skin goes inside the flue pipe from the stove and the outer skin goes over the chimney collar on the roof. The idea is that the condensation runs back down the inner skin, into the flue pipe and not onto the roof. The inner skin has to be a fairly good fit in the flue pipe otherwise the smoke and fumes can get into the void between the two skins. They then condense on the outer skin and run down onto the roof.
It's best to wipe off any stains as soon as they appear and they are not too difficult to remove. If they have dried, you might try T-Cut or even a lightly abrasive metal polish. However, if the stain has got into the paint, you may be too late.
In some cases, the staining runs along the roof and down the cabin side where a drainage gap in the handrail occurs. You can reduce this problem by positioning one of the vertical divisions between the cabin side panels where the staining runs down. If the division is a dark colour, the stain won't show too much or, at worst, you only have to repaint a relatively small area to cover the stain.

Graham Booth  | 6.45PM, Tuesday 28 March

Burning poorly seasoned wood and coal will produce smoke and tarry deposits inside the flue, especially if the fire is burning slowly.
Dry wood and smokeless fuel will produce fewer deposits. Running the fire nice and hot for a couple of hours each day will help burn off any flue deposits that form whilst the fire is just "ticking over".

Rupert Smedley  | 11.44AM, Wednesday 29 March


Readers say:

We use if we get any a degreaser spray from screwfix rub in with a piece rope so as no to dull the paint

mick turner  | 11.19AM, Wednesday 29 March

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