Hello,

We have a 4 unit condo built 6 years ago with a cinder block exterior and brick facade. Regretfully, I've since heard tradesmen call them ten year homes, since the cinder absorbs moisture and eventually crumbles away. Currently the blocks do retain some moisture after a rain (and dry in a day or two) but appear solid and mold free. We have collected a special assessment and are prepared to seal the entire building. What I'm wondering is what is the best way to have this project completed. I've gotten wildly different quotes (from 3-15K) and want to clearly define what’s expected in a properly completed job.

Here's what I have: looking for a company that will properly prep (i.e. clean) area, do minor tuck point or caulk as needed and apply a quality sealer.

My question is I've seen large variations in costs for sealant with warrantee’s from 2-15 years. Stuff for homes seems wildly expensive while commercial stuff (like you'd see on a Wal-Mart) seems more reasonable. Can anyone give a recommendation as to a quality sealer and how many coats would be necessary to complete the job properly; and I know this is a silly question but figured I’d swing for a ballpark on labor cost for a 4 story ~16,000 sq ft building.

Thanks in advance

 

Lets try and get clear here. Are talking about true "Cinder Blocks" or Concrete\LIghtweight Blocks? Cinder Blocks are rarely used anymore if they are used at all.

I have never heard such a thing about Concrete\Lightweight Blocks. They have been building with them for decades most structures hold up quite well if built correctly.

Though you would want them to be Primed and Painted correctly. Sorry can't advise on this one though. I know a "Block Filler" is recommended as a primer. Maybe the Painting forum can give some more info on this.

 

I've always known this style of masonry as "cinder block" although Concrete\Lightweight Blocks sounds more accurate since I doubt they are made of cinder. It’s my understanding that the higher quality blocks are manufactured with some waterproofing in the mix. I believe these are not "quality blocks" and was told that some of the smoother blocks used for textural detail should not have been used for exterior use. From what I can tell there are two major types of waterproofing a clear style that typically last only a few years and more of a paint style that's longer lasting.

Thanks, I'll copy the thread over to the paint forum in hopes of finding a painter knowledgeable in masonry painting.

 

When I listed Concrete\Lightweight Blocks this is 2 types of Blocks.

Concrete being heavier and more Water resistant and, hold up to constant moisture better. These would most definitely be used in Basements, Retaining walls they still need to be Waterproofed when used like this. They also are more heat resistant. Firewalls would be made of Concrete Blocks, though the Fire wall Blocks are a lot heavier and thicker structure.

Light Weight Blocks are just this lighter. They are made from different materials a mixture of Pumice, Haydite and other things. They are just about as strong as Concrete in tests. They do not hold up to constant moisture though. Not ideal for Basements and retaining Walls. These Blocks hold up fine in Walls again prober Painting will add to the lifespan of the Walls.


Now there is also some called Architectural Blocks. There are many types and looks they have a decorative surfaces and and are colored, in most cases they are not even painted. They are made from concrete and very heavy again.