Cleaning brick and repointing

[Michael6268]

I have a chimney that gets stained with creosote on one side due to a bad wind current/pressure zone that we live in. The chimney is the proper dimensions, 2/10 rule (actually exceeds that) etc, just an uncontrollable pressure zone. The smoke comes out of the chimney and usually travels down along side the chimney, down to almost ground level at times. The summer rains help to wash away the stains, but I was hoping to clean it and do a little minor re-pointing. Is there a good product to clean the bricks and cement cap. The bricks are an "aged" brick and are colored with white and black to make them look aged. Is there a way to clean the bricks without losing too much of the aged colors. Also will the run-off hurt my asphalt roof? As for the re-pointing, is portland cement ok?

 

[Mr_Super-Hunky]

Possibly consider getting a cheap sand blaster gun, hooked up to a compressor (or even an air tank....like a scuba tank) and blast it with a variety of media. Some to try would be glass bead, baking soda, or even very fine sand....gently.

There are even places you can order crushed walnut shells or corn cob media.

You can get the sand blast gun for $20 bucks or so (cheapy) and just hook up a hose to your compressor to feed. It will use A LOT of air so if your compressor is a smammer one, your "recovery" time will take a while. I have heard of people using a compressed air tank like a scuba tank with proper regulators to blast at the proper pressures.

The baking soda media will be the cleanest as much of it will float away as dust and anything left in obscure places will simply dissolve with the first rain.

 

[begreen]

I used dilute muriatic acid to clean up our bricks. It worked very well, but needs to be used with respect. If you choose to use it, do it after the pointing is done. I'd create a 2 ft. plastic sheeting barrier taped to the flashing around the chimney. When done, flush really well with a hose, including the roof.

There are other cleaning solutions that may be better. My job was for the old brick landings and steps we created. You might ask at the mason shop what they recommend.

Here's a link to some alternative recommendations that may be safer, especially for the roof:
http://www.doityourself.com/stry/bucketbrushcleaning