Ms Emmott made the comments after the business found that around 750,000 British homeowners have caused a total of £350 million worth of damage to their homes by trying to copy TV makeover shows.
She added: "Trying to tackle certain areas that you are not qualified for, such as electrics or plumbing could invalidate your home insurance and leave you liable for the cost of any subsequent damage.
"It's far better to employ a reputable tradesman than to risk damaging your home by going it alone."
A recognised high street brand, Halifax is part of the HBOS Group, which includes UK financial firms such as Birmingham Midshires and the Bank of Scotland.
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