DIY Home Improvement, Remodeling & Repair Forum

DIY Home Improvement, Remodeling & Repair Forum (http://www.houserepairtalk.com/forum.php)
-   Painting Forum (http://www.houserepairtalk.com/f107/)
-   -   Which Paint to use??? (http://www.houserepairtalk.com/f107/paint-use-9918/)

AdamP 09-11-2010 01:16 PM

Which Paint to use???
 
I have a question for the paint gurus out there. I want to paint the brick detailing above the windows on the outside of our century home white, as well as the window frames and sills. They are currently green. Only concern I have is that some parts are brick, some metal and some wood. Is there a paint out there that will work for all of these surfaces so I don't have to buy 3 different types?? Thanks in advance for the help!!! Adam!


Here is a pic of the house, it was built in 1875 with a large addition added in 1988!!

This is what it look like now.
http://i137.photobucket.com/albums/q...tonemapped.jpg

This is a photoshop of what I want to do!
http://i137.photobucket.com/albums/q...mappededit.jpg

Nestor_Kelebay 09-11-2010 05:29 PM

You should buy a "masonary paint".

The reason why is that nothing can damage masonary more quickly than it getting saturated with water, and then freezing. The expansion of the water inside the masonary creates tremendous pressures that result in the surface of the masonary breaking off in chips; a process called "spalling".

Masonary paints are latex paints where the binder resin in the paint has been chosen based on it's ability to allow individual H2O to pass through the paint, but not liquid water.

The way this is accomplished is easily understood if one considers a plastic polymer molecule to be a long wire that's been scrunched up into a ball. Despite it being scrunched up, there are still gaps between the wires in this ball that something like sand, say, could pass throught.

In masonary paints, the gaps within the binder resin (the scrunched up wire) are larger than the diameter of a single H2O molecule, but smaller than the average distance between H2O in liquid water.

As a result, H20 molecules can pass through the paint film relatively easily, but not liquid water. This allows the paint film to work very much like a check valve; allowing moisture inside the masonary to evaporate through the paint film, but preventing the masonary film from absorbing water when it rains. Thus the masonary stays drier than it otherwise would, minimizing the possibility of freezing damage.

Unfortunately, my understanding is that you're painting over paint. If the existing paint is not a masonary paint, then painting over it with a masonary paint won't give you that "check valve" benefit that you buy the masonary paint for.

To get that benefit, you'd have to remove the existing paint from any masonary you want to paint over with masonary paint. And, every time you repaint that masonary, it'll have to be with another masonary paint in order to retain that benefit.

A masonary paint is very similar in every respect to any other exterior latex paints. The quality that differentiates it from other latex paints is the size of the spaces between the scrunched up wire in the binder resin, which is something you can discern. So, you can use a masonary paint over painted metal and wood exactly the same way as you would with any exterior latex paint.

Using a masonary paint over wood has the same benefit in that it keeps the wood dryer, but wet wood doesn't crack when it freezes like masonary does.

I would scrape the old paint off the masonary you want to repaint, and paint it with a masonary paint. Otherwise, you can paint it with any exterior latex paint as the previous owners probably didn't know enough about paints to have known to use a masonary paint.

Also, don't confuse a masonary paint with a concrete primer. Concrete is highly alkaline during the first few years of it's life, and that high alkalinity causes chemical degradation of paints that aren't highly alkali resistant. Concrete primers are highly resistant to alkalinity. Masonary paints aren't necessarily so. Masonary paints claim to fame lies in their ability to allow H2O molecules to pass through the paint film.

I'm not endorsing anyone's paint here, but most paint companies have a masonary paint in their line-up. Canadian Tire sells "Armor Coat Masonary Paint".

http://img2.shoptoit.ca/images/thumb...0/43217820.jpg

Canadian Tire isn't reknown for the quality of their paints, but if were my house, I'd paint your brickwork with Canadian Tire's Masonary paint before I painted over that brickwork with anyone else's top-of-the-line exterior latex. That's because the binder in the masonary paint would have been chosen for it's ability to beathe, whereas in a top of the line paint it would be chosen for all around best performance. And when it comes to masonary, keeping it dry is more important than having to repaint very 20 years instead of every 25. Just my opinion.

Hope this helps.

AdamP 09-11-2010 06:38 PM

Thanks for the help!! Much appreciated!

NJ Coatings 11-04-2010 01:52 PM

I think Nestor's solution is the best only i'd recommend that you also seal the masonry surface first.

The reason is that brick is very porous and the one thing you don't want is liquid moisture getting behind your coating. As Nestor pointed out, the masonry paint will keep it out where it exists but moisture may be absorbed from adjacent brick above and to the sides and migrate behind the painted area causing delamination.

Sealing the brick first would help eliminate this problem and is a really good idea for protecting your brick surface anyway. Absorbed water in masonry freezes and can cause cracks.

DrHicks 11-08-2010 08:39 PM

No paint advice, but holy cow - GREAT HOUSE! I absolutely LOVE old houses!

Our house is an old 2-story brick (built in 1928) that is about the same color as yours. LOVE these houses!

kzhen8 08-15-2011 03:45 PM

The best paint out there to me is Sherwin Wiliams paint and it goes well with brick, metal, and wood in my opinion. You can take a look at the search that I have refined for you here: Sherwin Williams Paint White - Lowest Prices & Best Deals on Sherwin Williams Paint White - Pronto.com I'm curious as to know what paint you ended up using or will use?


All times are GMT -6. The time now is 09:16 AM.