What’s the best material to use for backfilling drilled holes through 9” solid brick and lime mortar walls?. I’m looking to have a couple of outside taps installed at different locations which will be connected to the internal cold water main hence the need to drill two seperate holes through the wall. The ideal material would seem to be the expanding foam which can completely surround the pipe and fill the entire 9” depth of the hole but I’m sure you will have other suggestions. I will also be looking in the future to install a drainage pipe through the wall for sink/ washing machine etc. so a much larger bore than the two outside taps. I don’t think the foam would be suitable in that instance?
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What material for back filling drilled holes?
- Thread starter michael
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Penners
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- Suffolk, England
In an instance where the filler doesn't have to provide any structural support for the masonry, I'm an enthusiast of PU foam. It has the advantages of (a) being completely waterproof (indeed it sets better in the presence of moisture), (b) insulating the area of the hole, and (c) never cracking.
I usually wait for several days to be absolutely sure that the material has finished curing, and reached equilibrium. On the outside of the wall, I then cut it back to a few mm below the surface of the wall, and face it with a material that is cosmetically the same as the wall - eg, coloured mortar or similar.
I usually wait for several days to be absolutely sure that the material has finished curing, and reached equilibrium. On the outside of the wall, I then cut it back to a few mm below the surface of the wall, and face it with a material that is cosmetically the same as the wall - eg, coloured mortar or similar.
chuckey
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You say " solid brick and lime mortar wall", i.e. brick, get the right size bit for either case = diam of pipe + 1mm and squirt a bit of silicone around the outside crack, though its not really required. If you are contemplating squirting foam into the wall the hole has to be 6mm + larger then the pipe to get the nozzle in. Also the amount of foam used would be a 1/2 second burst, with about 50% of it to cut off the next day. If you want to pretty it up, use the right size drill and chip of the edge of the hole to provide a border of 10mm "pointing", if you can match the mortar colour.
Frank
Frank