How should I clean this roof

EastBelfastian · 1 May 2020

This is the roof outside my bedroom window. I was thinking of pressure washing it - but should I use some pre-treatment? Should I pressure wash it at all? I would like to do a super duper job on it if I can!

[GALLERY=media, 104385]IMG_20200501_163314 by EastBelfastian posted 1 May 2020 at 5:48 PM[/GALLERY]

Open to tips and suggestions

noseall · 1 May 2020

Leave it alone.

Johnny Allround · 1 May 2020

If you really need to it will brush off when it’s dry.

Nige F · 2 May 2020

As per Nose ... don't wash it , you'll get water forced in round those velux. Modify a brush - maybe a drain brush on some rods ? then brush down from the window and pull down from the ground. DO NOT be tempted by ANY roof cleaning/coating scams !

Vinty · 2 May 2020

You dont need to powerwash your roof, Spray the roof with moss killer and leave it, once the moss dies it will shrivel up and wind, rain and gravity will wash the moss down into the gutter.
Will take a bit of time though.
https://www.wetandforget.co.uk/?gcl...tbqMcSxUhr6qiS3QFW7MDa3ITyKKsRpUaApWBEALw_wcB
This stuff here can be used on roof tiles as well as patios.https://www.wetandforget.com/blog/2018/06/21/roof-cleaning-101/

noseall · 2 May 2020

I'm seeing Marley 'Bold Roll' tiles - as rare as rocking horse sheite. You would have to be a total nutter to mess about with that roof.

catlad · 3 May 2020

Those moss killer spray on products may damage the alloy skylight flashings

Vinty · 3 May 2020

noseall said:
I'm seeing Marley 'Bold Roll' tiles - as rare as rocking horse sheite. You would have to be a total nutter to mess about with that roof.

More likely those tiles are redland regent, easy enough to get. https://redland.co.uk/products/profile-range/regent

Vinty · 3 May 2020

catlad said:
Those moss killer spray on products may damage the alloy skylight flashings

Years ago our firm used to carry out storm damage work for insurance companies.
After a storm we would get sent to jobs that included repairing leaking Velux type skylights.
One of the most common causes of leaking around these type of skylights was the flashings which go underneath the tiles getting blocked with moss causing rainwater to overflow underneath the tiles onto the felt below.

catlad · 6 May 2020

Yes I know! I was only making people aware that some of those chemicals are very corrosive.