If the content of makeover television programmes reflects our tastes in home alterations these days, perhaps it’s time to worry, because lately our tastes have turned distinctly hardcore.

What started off a few years ago as a harmless inclination among homeowners towards

a little bit of slap and redecoration has now evolved into an appetite for full-on demolition and reconstruction.

According to the Irish Georgian Society (IGS), our period homes are victims of our enthusiasm. In the past, typical assaults on period houses were ill-advised window replacements and paint jobs, but these days well-intentioned homeowners are more likely to destroy entire walls.

The society is running a campaign to educate people who heavily renovate period homes without fully understanding the process. According to Mary Bryan, the society’s chief executive officer, even seemingly small mistakes can wreak huge amounts of damage.

“One of our hobbyhorses at the moment is the use of unsuitable plaster and repointing materials,” says Bryan. “What people don’t realise is that most houses built before the early 20th century were porous — they needed to breathe.

“They were plastered and filled using lime-based materials which allowed this. People now come along and repoint and replaster using cement-based materials which are effectively sealants. The result is that the moisture finds its way through the bricks instead and destroys the structure of the house.”

Common mistakes include shoring up vents inside or sealing up fireplaces, also a necessary part of the ventilation in a period home.

Other blunders interfere more with the visual integrity of the building than its structure. Replacing wooden sash windows with uPVC versions and painting over brickwork are frequent errors.

Lately there has been a trend towards extending period homes with modern glass extensions, a practice which the society believes can also lead to serious structural problems unless the correct expertise is employed.

“An architect may be good within their chosen field, but that does not necessarily mean they understand the intricacies of period homes,” warns Bryan.

The IGS carries a list of recommended engineers, architects, craftsmen and materials experts on its website, but for those who wish to restore a period home to original and authentic condition, a field trip could be just what the house doctor ordered.

While plenty of period properties have been converted for modern use, there are few restored as full-blown museum pieces. While an owner might not want to revert to burning whale oil lamps and using commodes, it is useful to

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