[simon w]

Does anyone else use the 22 litre Gardiner back pack to apply hypo for render cleaning? if so I was wondering if you could recommend a water-hypo ratio for 15% S H for render cleaning? I know this has to be altered slightly depending on how dirty or clean the render is. I was thinking 18 litres of water to 4 litres hypo allowing for surfactant to be added.

I was also planning on making up 25 L barrels of pre mixed hypo the night before a job would a ratio of 21 L of water to 4 L hypo be suitable for render cleaning then just decanted into the back pack whilst working

[SB Cleaning]

Your thinking along the right lines

I would use a bit of surfactant too.

[Splash & dash]

Does anyone else use the 22 litre Gardiner back pack to apply hypo for render cleaning? if so I was wondering if you could recommend a water-hypo ratio for 15% S H for render cleaning? I know this has to be altered slightly depending on how dirty or clean the render is. I was thinking 18 litres of water to 4 litres hypo allowing for surfactant to be added.

I was also planning on making up 25 L barrels of pre mixed hypo the night before a job would a ratio of 21 L of water to 4 L hypo be suitable for render cleaning then just decanted into the back pack whilst working

That’s fine but I would mix it on the day not the night before

[Smudger]

yes only mix on the day

personally I'd go a little stonger @ 3 parts water 1 part SH  - that pretty well removes everything other than black spot

Darran

[simon w]

Thanks for all your replies guy's, mixing just before use, surfactant and a slightly stronger mix as Darren has suggested it is then.