Handy Mac, aka Don MacAlister, is our expert on household DIY issues

Firstly, in an ideal world all water should be drained away from a house, but this is never going to be achieved 100%. Just keep it to an absolute minimum and wherever possible never have flower beds next to house walls and don’t install sprinkler systems

ANON is itching for me to help with her problem:

The managing agent in my block had my bath resurfaced, and I have a severe allergy to the product used. The franchise owner said no one has ever had this reaction, but he checked with head office and people have been known in testing phases to be sensitive to xylene used to resurface the bath (it’s one of the main solvents in the product). I have a terrible rash and can’t use my bath. Help.

I could easily go off track here as Anon has touched on two of my pet hates, baths and managing agents. I am a hot, strong shower man, unless I am in an area with an unlimited water supply and a huge hot water geyser and I have hours to waste for a deep, long soak. I think I had a dig at managing agents the other day. There are some great ones who care about their clients, but many more who are supposed to look after property but don’t know the difference between a nail and a screw.

This is the first time I’ve heard about a bath resurfacing causing an allergic reaction. I have had many baths reglazed for clients over the years, including two floors of a hospital with baths in many of the wards, without any comeback. However, I began a Google search (thanks to Mrs Mac, who bought me a new laptop for my birthday) and what’s the first thing I find? At least 14 workers have died since 2000 as a result of using stripping agents containing methylene chloride during bathtub refinishing. Many stripping products (including those that may also be available to consumers) contain high percentages of methylene chloride. Methylene chloride is extremely dangerous when not used correctly.

In February 2012, a worker using a product containing methylene chloride to refinish a bathtub was found dead, slumped over a bathtub in an unventilated bathroom. In September 2011, a worker using a product containing methylene chloride to strip the glaze from a bath collapsed in the tub and later died.

It would appear the dangerous part of this operation is the initial stripping. I wonder if you have come into contact with something that has been left behind, or whether during the finishing process, which usually involves sanding down which causes a fine powder residue to hang around in the air or on surfaces. The contractor failed to clean up properly.

I believe that would cause skin irritation, especially if there is any fibreglass involved.

Unfortunately, every human is unique and not every product can be tested on an entire populace, so there is always going to be – with respect – the odd person who will suffer a bad reaction.

This case proves once again there is danger lurking around every corner and that we need to check every product with which we come into contact.

There is absolutely no reason for any contractor to blame ignorance about the products they use as modern technology covers every angle of daily life. A FEW weeks ago, you wrote about rain drainage and keeping it away from the house. Please look at my situation and evaluate.

The previous owner had a band of cobbles about 80cm wide laid around the entire house. However, there does not appear to be a watertight join between them and the walls. They also do not appear to have been laid with any slope away from the walls. Also, one of the roof downpipes goes into another that disappears under the house between the garage and the kitchen. They share a wall.

I have had a plumber put a camera down and he says it ends somewhere under the house and apparently does not extend on the other side. I have put a pipe in to lead off as much rain as I can, but the fall of the drive cobbles slopes down to this drain. Am I sitting on major disaster? So far, I have not seen damp or cracks on the walls.