Pool acid not a solution to sandstone stains
A friend has sandstone tile steps that have developed black marks that look ingrained. How can he get rid of these marks? My husband said to try pool acid, but ...? – HW, Port Elizabeth.
Sandstone has a relatively weak, porous structure. This makes it susceptible to stains, and, for this reason, sandstone tiles are usually sealed. Outdoor sandstone is often stained by organic materials such as leaves, tree sap or mould and mildew.
Because it is so easily marked, sandstone has to be carefully cared for. Floors should be cleaned daily, and spills should be treated with a damp sponge and warm water.
At this stage the marks on your friend's sandstone are certainly ingrained. Even so, it may be worth giving them a good scrub with a soft bristled brush and warm, soapy water.
Pool acid is certainly not the answer. Any acidic cleaner will etch the stone, so even lemon juice and vinegar can cause stains. Chlorine bleach will also damage sandstone, but according to a post on Google, milder 30/40-volume hydrogen peroxide, obtainable from the pharmacy, may be used for mildew and organic stains. This may be worth a try. Absorbent material, such as talc powder, can be used for oily stains. I'm afraid that the tiles may have to be sanded down to remove the marks, and then be sealed with a suitable commercial product. This may affect the colour of the stone. I got in touch with Bennie GrisseI at Tiling Contractors. Not surprisingly, he said one needed to establish the cause of the stain if possible. He mentioned a product called Lift Off Tile Doctor, which is diluted according to the severity of the problem.
I have a duvet cover which has acquired perspiration marks along the whole length of the top edge. It is cream in colour. Do you have a "trick" to get rid of these marks? – HR, Port Elizabeth.
If perspiration stains don't come out in the normal wash, wet the fabric and treat with household ammonia straight from the bottle. Then rinse thoroughly. A soak with strong cold water detergent should also work. Other methods are to sponge with a weak solution of white vinegar and water, or lemon juice.
In all cases, rinse very well and then launder as usual.
I read in your column about the damp problems in the house in Walmer. We have had two cases of damp walls, both external and facing south, and successfully treated both walls with Drycote, obtainable from Chryso SA in Lorraine. The first wall treated was of facebrick and the second a plastered wall.Drycote is a colourless liquid which is simply painted on. The product was recommended to us by an experienced builder. – MR, Port Elizabeth.
Many thanks for the advice. It is always good to hear about a product that has been used successfully.
I saw your item about shredding documents. I had a problem until I decided to immerse the papers in cold water, and allow them to soak well. Separate the pages a bit, and then just mash them into pulp. This makes a big mush, so the papers are totally destroyed. Then put in a plastic bag and place in the garbage. – DL, Port Elizabeth.
Thanks for the tip. It certainly sounds like a foolproof alternative. I wonder if the "mush" can be recycled?
Incidentally, people who read the item in the column a few weeks ago about recycling plastic may be interested to know what the numbers in the triangle emblem represent. I've been told that they refer to the density of the plastic. Water bottles, for instance, have a "1", milk bottles a "2" and food wrapping a "4".
- At Your Service, with Gwen Bisseker
