Paint… What to know: part III

Now you have learned about exempts solvent and their connection to VOC regulations, now lets look at some other tricks that happen in this VOC -hyper world.

As we have learned, manufacturers have to meet certain levels of VOC’s in order to be considered a low or zero VOC paint.  For low-VOC paints, it ranges from 50g/L to 150g/L (based on sheen, eggshell and semi-gloss being permitted to have more VOC’s) and in order to be considered a Zero-VOC paint, it must have less than 5g/L.  But the regulations are based on the measurement of VOC prior to pigments being added.  Pigments contain a high level of VOC’s and once added to the paint, if tested, you would find that this paint now exceeds those regulations.  This is especially true of Deep and Accent bases because it is necessary to add more pigment into those bases in order to achieve the desired colors.  Pastel and Medium base paints have minimal amounts of pigments added and therefore typically stay close to the original base measurements.  So the paint you buy may not be the paint you get unless the company you are buying it from has Zero-VOC pigments.  These pigments come from the same manufacturer, Degussa, they cost a little bit more, but are easy for anyone to order.  I can tell you with assurance that there are only a handful of companies using Zero-VOC pigments in the valley so it pays to ask them when you buy… or don’t buy.

The next thing to know about paint has to do with the Solvent and the Solids.  You can tell a lot about paint by looking at the % Solids by VOLUME of a paint.  There is another measurement, % Solids by weight which is more misleading as we will discuss.  So the % solids by volume will tell you how much of the paint is solvent and how much is solids.  You want a higher content of solids for two reasons… Solids are what is left on your wall after the paint is ‘dry’ (read: the solvent evaporates).  Reason one, solids are what gives you a durable finish that is resistant to scuffs and washing and therefore make it more durable and reason two, the more solids the better the coverage over other colors or the primer will be, therefore reducing the number of coats you will need to do.  There is a direct correlation to a low % solids and cheap chemicals and therefore cheap paint overall.  Just remember, cheap paint, cheap ingredients.  So look for high % solids in your next purchase… you want to look for paints 38% and higher.

We mentioned % solids by volume above.  This is a shady one because as we saw in the previous sections, manufacturers can use exempt solvents that are highly toxic like acetone and they are being encourage to do so, so they can meet the VOC regulations that exist.  But solvents like Acetone are lighter than water, which means i can replace an equal amount of water with Acetone and the % solids by weight will increase, even though i didn’t add any more solids.  Just another trick to watch out for.

Next we will look at Low-Odor and some final thoughts on paint.


Leave a Reply

Fill in your details below or click an icon to log in: Logo

You are commenting using your account. Log Out / Change )

Twitter picture

You are commenting using your Twitter account. Log Out / Change )

Facebook photo

You are commenting using your Facebook account. Log Out / Change )

Google+ photo

You are commenting using your Google+ account. Log Out / Change )

Connecting to %s