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View Full Version : Painting masonry - Stone or brick



Hollis Brown
07-04-2013, 01:04 PM
How big of a deal really is it that the masonry has been painted. I understand that once it's been painted it now has to be maintained, but is that the only downside?

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Raymond Wand
07-04-2013, 01:33 PM
Dependent on type of:

1. brick, clay or cement
2. age of brick/house
3. type paint - does it breath?
4. how long paint has been on the brick
5. any current signs of deterioration
6. construction and weatherization type - ie. house wrap, vapour barrier, etc.

If there is no spalling or bubbling and paint has been on for quite awhile then it may be nothing to worry about.

Mike Lamb
07-04-2013, 09:54 PM
How big of a deal really is it that the masonry has been painted. I understand that once it's been painted it now has to be maintained, but is that the only downside?

29068 29067

If the correct paint is used, yes, that is the only downside.

Raymond Wand
07-05-2013, 03:59 AM
Paint can also hide repairs.

The first picture looks like improper mortar repair and damaged brick.

Garry Sorrells
07-05-2013, 06:26 AM
If moisture gets into block/brick, and the paint has it sealed in, a concern is what happens when it freezes. The moisture may take years to build up before it starts to blow apart the surface....

Mark Reinmiller
07-05-2013, 10:25 AM
Dependent on type of:

1. brick, clay or cement
2. age of brick/house
3. type paint - does it breath?
4. how long paint has been on the brick
5. any current signs of deterioration
6. construction and weatherization type - ie. house wrap, vapour barrier, etc.

If there is no spalling or bubbling and paint has been on for quite awhile then it may be nothing to worry about.

I have probably seen at least 1000 painted stucco, brick, or stone walls. I would say that generally it does not hide much or cause much problem. This assumes that the paint is water-based so it is not creating a moisture barrier. I am in the mid-Atlantic region with a lot of old masonry. Of course, if the masonry looks spalled, damaged, or patched, then no telling how long the repair will last.

A couple of other points. If it was stucco on frame and about 25 years old or less that would be a red flag. I just inspected a stucco on stone house (early to mid 1800s) that was painted. I saw a few cracks and knocked on the wall. Where it sounded hollow I could tell the stucco was delaminating. Not unusual for that type of house, but good to point out.

Bob Harper
07-08-2013, 08:36 PM
The BIA has stated do not coat or paint any type of masonry unless the coating is 100% vapor permeable. Masonry is a big sponge and must breathe. If it cannot dry to the exterior it will trap water inside. While walls open to the interior of a house do tend to dry to the inside, masonry and stucco chimneys experience water damage much faster and to a greater degree than uncoated ones. Very few coatings are truly 100% vapor permeable. The best water repellent on the market is ChimneySaver in my book. NEVER, NEVER use Thompson's, any paints or pain on sealants. They will trap water vapor and kill the masonry or drive up indoor Rh%. Not sure what you guys have been looking at but almost every painted chimney I've seen has accelerated water damage.

H.G. Watson, Sr.
07-09-2013, 07:21 AM
The BIA has stated do not coat or paint any type of masonry unless the coating is 100% vapor permeable. Masonry is a big sponge and must breathe. If it cannot dry to the exterior it will trap water inside. While walls open to the interior of a house do tend to dry to the inside, masonry and stucco chimneys experience water damage much faster and to a greater degree than uncoated ones. Very few coatings are truly 100% vapor permeable. The best water repellent on the market is ChimneySaver in my book. NEVER, NEVER use Thompson's, any paints or pain on sealants. They will trap water vapor and kill the masonry or drive up indoor Rh%. Not sure what you guys have been looking at but almost every painted chimney I've seen has accelerated water damage.

Lime wash/lime-based "paint" to a properly prepared surface accomplishes that quite nicely. Its a method that has been used for hundreds, if not thousands of years.

Raymond Wand
07-09-2013, 05:16 PM
Never seen a home painted on exterior with white wash, basements yes, interior barns yes and in some case the exterior barn foundation.

Basic limewash can be inadequate in its ability to prevent rain driven water ingress. Recent weather pattern changes in the UK has allowed some limewashed buildings to reach internal saturation. Additives are being developed but these have the potential for affecting free vapour permeability, for this reason silicate paints, more common in Germany, are gaining popularity in the UK over limewash.