Dear Donny

Q I’ve spilled nail varnish on our Indian stone patio. I have tried nail varnish remover and brushing with neat bleach but neither worked. Please help!

Polly Allen, by email

A You could apply an acid wash for persistent stains that won’t weather away. Wet the paving first to prevent the acid being absorbed, apply it and scrub with a stiff bristle brush before rinsing. Lithofin MN Builders’ Clean might also do the job.

Q Our fridge has a drain at the back of the food compartment, where the cooling surface is, which gets blocked. Is there a cleaning fluid which will clear out the pipe? Robin Smith, by email

A You need a Diversitech Gallo Gun drain line cleaner. It uses a compressed CO2 cartridge which is inserted into the gun. Feed the tube into the fridge pipe, pull the trigger and the pipe will be instantly cleared.

Q I want to paint the inside of a polycarbonate conservatory roof. Is there a product you would recommend please? Jacinta West, by email

A It’s not something I’d do, mainly because of the heat that will end up being trapped. But, if I was going to attempt it I’d use something like Zinsser Bulls Eye 1-2-3 as it sticks to plastic. However, remember that a conservatory roof gets very warm during the day and very cold at night, so the paint has to be able to accommodate this or it might crack.

Q What’s the right type of screw to use when fixing a 45mm timber to a joist?

Darren Anderson, Fife

A The screw length must be three times the thickness of the timber you’re fixing, so that two-thirds of it will be sunk into the joist. So, you’ll need a 135mm screw as a minimum.