Blot From The Blue
The Age
Sunday May 21, 1995
Q: WE HAD some white vinyl exterior cladding over weatherboard professionally fitted about eight years ago. Both material and job were excellent but stain removal is a constant failure. We are left with apparently irremovable stains, brown or black, either from birds or insects. We live in the dry, dusty Wimmera.
As vinyl is the material, I am reluctant to try petrol or something similar. Test-patch tar remover was of no benefit.
Derek E. Breed.
A: VINYL and polypropelene building materials are particularly prone to marking and semi-permanent staining by a wide range of agents.
Vinyl used in the manufacture of weatherboard cladding is also marked by contact with household and garden equipment. In areas where the environment is damp and overgrown, mould can also cause unsightly black stains on the vinyl cladding.
Insects and nocturnal bugs will deposit nasty residues on the vinyl cladding. These residues are quickly absorbed into the vinyl fabric and the hard-baked deposits become difficult to remove.
In my recent visit to the United States, I found that aluminium weatherboards are regularly cleaned by specialist contractors using commercial detergents and high-pressure water lances in the more salubrious suburbs. But I found no evidence of contract cleaning of vinyl building products.
Vinyl weatherboards are not as easily cleaned as aluminium products because vinyl and polypropelene are detrimentally affected by spirit- based solvents and petrochemical reagents. You should not use any solvents without reference to the manufacturer of vinyl cladding. Most installations have a brand mark or contact number on the fabric.
Most marks on vinyl weatherboards can be removed using ammonia-based household cleaning agents such as Jif. Household detergents will not always work.
My recommendation is to first wet down the soiled and marked weatherboards, allow the stains to soak for a short time, then scrub the affected area with a neat application of the ammonia-based cleaners. Use a bristle brush and scrub the stain out. You can use hot water to assist the action.
For difficult stains, you should use a 10 per cent solution of cloudy ammonia in cold water, and scrub gently in a rotating action. Use protective gear and try a test patch first. Cloudy ammonia is a strong solvent and will usually remove the organic stains such as you describe.
Allan Willingham is on 3LO at 7.10am each Saturday. If you have a home maintenance question, write to Allan Willingham, Home Weekly, PO Box 2417V, Melbourne 3001.
© 1995 The Age