Using dirty water for cement

[ScubaDave]

Hi.

In renovating the roof and walls of an old building, an old, open galvanized water tank is right at the only sensible location to stand a cement mixer. It is filled with brown water and long-decaying branches and other debris can be found at the bottom of the tank. Clean water is available but less convenient.

There have been discussions on site regarding the appropriateness of using water from the trough for making cement.

Is the dirty water fine to use or not..? Is there any evidence or support for either viewpoint..? What might be any consequences for using the dirty water instead of clean..?

Many thanks.

 

[conny]

You should always use clean water.
You have no idea what contaminants are in the tan, plus if it's rusty, there will be a lot of ferrous oxide floating free. Ferrous oxide is basically rust and it may show in the mortar and I think it would certai9nly weaken the mix.
Get shut of the tank and use a long hose to reach to the site.

 

[freddiemercurystwin]

I suspect realistically it probably wouldn't make much difference in a domestic setting, it's no doubt used in many foreign country's where clean water is simply unavailable but then they have lower standards. Guess it depends what you're using it for. I'd be less concerned if I was say doing an 800mm deep foundation as opposed to doing a 100mm thick ground floor slab.

 

[Deluks]

Cement you say? Assume you mean mortar? To build the walls up with?

Not a chance, buy a hosepipe.

 

[jeds]

As fmt says, manufacturer says clean water, but you could take a view depending?