Hi
Trying to fix a longstanding problem. But a bit of background first.
Block-built and rendered porch at the front of the house, render finishes about 10" short of the ground. Blocks painted black at ground level.
I couldn't find out why the blocks in the one corner of the porch were spalling - see picture.
Eventually worked out it was a leaking ch pipe joint beneath the floor of the porch - the water was soaking through the blockwork from the inside, then freeze-thawing on the outside, causing the spalling.
Leak stopped, so no more water soaking the blocks. Blocks have been scrubbed back to sound surface.
What mix, technique, and process should I use to patch repair this with render? I've never done it before, so I need even the basics explaining.
I'm guessing I'd have to soak the blocks first (reduce suction). Would it be a two-coat job? What mixes to use? What is the consistency of mix I'd need? I guess too creamy would slump?
It'll be painted later with black masonry paint, to blend in.
Thanks in anticipation
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Trying to fix a longstanding problem. But a bit of background first.
Block-built and rendered porch at the front of the house, render finishes about 10" short of the ground. Blocks painted black at ground level.
I couldn't find out why the blocks in the one corner of the porch were spalling - see picture.
Eventually worked out it was a leaking ch pipe joint beneath the floor of the porch - the water was soaking through the blockwork from the inside, then freeze-thawing on the outside, causing the spalling.
Leak stopped, so no more water soaking the blocks. Blocks have been scrubbed back to sound surface.
What mix, technique, and process should I use to patch repair this with render? I've never done it before, so I need even the basics explaining.
I'm guessing I'd have to soak the blocks first (reduce suction). Would it be a two-coat job? What mixes to use? What is the consistency of mix I'd need? I guess too creamy would slump?
It'll be painted later with black masonry paint, to blend in.
Thanks in anticipation
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