I have a 50 year old cinder block (when you drill into it is black/gray) foundation that has a few irregularities, cracks and several coats of paint on it. I would like to parge the whole mess to cover up the worst of it.
My question is do I need to cover everything with wire mesh screwed to the block and then parge or can I get away with powerwashing any loose stuff and applying a bonding agent to the wall, then parging? Any other suggestions? Thanks.
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Replies
troy, I have used Durabond to fill the mortar joints and the first skim on painted block both below and above grade. Never used a bonding agent, tho I don't think it would hurt. Finished with regular bucket mud. They have lasted. Remember of course, moisture from the outside can push off anything you put on block
Remodeling Contractor just outside the Glass City.
Quittin' Time
Edited 4/14/2005 10:09 pm ET by calvin
I have used Thorobond bonding agent...paints on with a brush...reddish color. I then go over top with Quickcrete's fiber cement ( also known as B-Bond...is a cement mix fortified with chopped fiberglass). Trowel the B-Bond for a nice finish.
If unable to find Thorobond...use Acryl 60 for a bonding agent...this stuff goes into the cement mix as an additive rather than being painted on the cinder block . Either should work well.
If unable to find B-Bond...use Thoroseal...this stuff will adhere just fine...is used for dressing up cinder block all the time...only problem I've noticed is that if applied too thick, it will eventaually crack. B-bond could also crack, but I seem to have better luck with it.
Davo
i think you can power wash it... with a real power washer ...something like..3500 psi belt drive unit min with a turbo nozzle... 10-15 hp
point up/skim over... the bad places with a rich portland/sand mix after apply'n it i use a scrap of white styrofoam to rub it down circular motion blends it in well... do this on a damp wall... keep same damp fo a min of a 3-4 hours... 2-3 days is better... damp not wet... then i mix a mix of 1 part portland 1 park fine clean white sand... i use white portland with a touch of gray portlant to knock out the "white whiteness" i mix this pretty wet and i scrub it into the wall... i use acid wash brushes that are made for acid clean'n new brick... this stuff will set up quick... again... apply it to a damp surface and keep it damp... it cleans up ur old surface well and should last for years
pony
Thanks for all the info guys, you have saved me a ton of work as I was leaning towards overkill and adding the mesh. One more thing, around the basement windows is older 2x PT wood that has shed most of its paint, could I clean this up and parge over this as well or would this require mesh? I am pretty sure it will require mesh, but I can hope!
Just personal opinion, but I wouldn't parge over wood, even pressure treated.