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Chemical warfare

27 Nov 18 The damp-proofing and timber preservation industry is fighting a desperate battle to retain the right to use chemical products that many conservationists claim are useless and can even damage old buildings. David Taylor reports

In August of this year, the Property Care Association (PCA), a trade body representing damp-proofing and timber preservation specialists, announced that it was “taking pre-emptive action to help secure access to vital products used in the protection and preservation of UK buildings”.

The association’s pre-emptive action was to launch a one-day training course and professional-use register designed to enable users of biocides in wood preservation products to “demonstrate their specialist credentials in the safe and effective use of timber protection chemicals”.

Steve Hodgson, the PCA’s chief executive, explained that over the past few years, restrictions on the use of biocides have affected the availability of timber protection chemicals.

In an announcement to the press, Hodgson said: “Within this regulatory framework, many products used to control timber decay and wood destroying insects have now been withdrawn. Others can now only be used by professionals.

“If we lose the remaining formulas it will cost property owners a fortune as they face the significant consequence of their property being effectively ‘written-off’.

“Therefore it really is vital we protect these biocides by providing a route for home-owners and property professionals to seek out professional users who are trained, skilled and competent in the application of these products,” said Hodgson.

Concerns over exposure to potentially toxic chemicals and, more recently, a growing awareness of the harmful effects of air pollution, have meant people now treat pesticides and fungicides with more caution than previously, says Hodgson.

“Fifteen or 20 years ago, there was a whole gamut of products available – some of them pretty nasty, like lindane and TBTO [tributyltin oxide] – a whole stack of them that are not used today,” he says. “But what really affected their availability was the biocides directive that set new standards for registering formulations.”

The European Biocidal Products Directive (1998) required producers of chemical products to get official approval for each biocidal application – a lengthy and expensive process. “Even products with very limited uses – safe or not – have to go through the same process, and it costs a lot of money,” explains Hodgson.

As an illustration, Hodgson cites permethrin, a very common pesticide used in many industries. “Nobody owns it – it’s generic. So who’s going to waste a load of cash to get this approved for a specific application?” To do so, says Hodgson, would effectively mean paying so that your competitors could register their own permethrin-based products for free.

Consequently, the range of chemicals available to the industry is getting smaller and smaller. “It’s a perfect storm: very few products available, and very few people willing to invest in what’s actually a tiny market,” says Hodgson, “Innovation is almost impossible; the cost of getting products to market is prohibitive.”

But it’s not just a concern for health, safety and the environment that is driving restrictions on the use of biocidal chemicals in building preservation. There is also a growing consensus in the building repair and maintenance sector that these chemicals are not only toxic to humans but actually ineffective and unnecessary in combatting insect and fungal attack.

“There has in the past been an over-use of chemicals to deal with moisture-related problems. But it’s moisture, and the ‘green’ way to deal with it is to get rid of the damp,” says John Edwards, a chartered surveyor and director of historic buildings consultant Edwards Hart.

Applying biocides to timbers suffering the effects of damp is “treating the symptom, not the cause,” he adds.

Edwards was the lead author of the 2013 revision of BS7913 Guide to the conservation of historic buildings which draws on a wide range of specialist sources to provide a comprehensive best-practice guide to building conservation.

First published in 1998, BS7913 is reviewed every five years. The 2013 review led to a root-and-branch revision of the standard, says Edwards. “Once BSI had done their business case, they assembled a committee with representatives from all sorts of organisations including English Heritage, RIBA, the National Trust and SPAB [the Society for the Preservation of Ancient Buildings]. It was essentially a complete rewrite, bringing lots of areas of best practice into one document,” he explains.

The revised standard introduced a number of fundamental changes. First, it made it clear that it applies to all old buildings, not just listed structures, as had previously been widely assumed. According to Edwards, it applies to approximately a quarter of the UK’s building stock. “I do recall the PCA saying the standard was not applicable to buildings that weren’t protected, but that’s not the case,” he says.

In a review of the new standard, published in 2016, the PCA set out its own understanding of what constitutes an ‘historic’ building: “The dictionary provides the following definition: ‘famous or important in history, or potentially so’.

“Unfortunately we have seen references to the application of this document to any building constructed before 1919. This interpretation of the reach of the document is misguided and plainly wrong,” is adds. The suggestion seems to be that only famous or exceptional old buildings deserve the care deemed necessary by BS7913 but lesser buildings are excluded, even if the same treatment is the most appropriate for their maintenance and repair.

"It's a perfect storm: very few products available, and very few people willing to invest in what's actually a tiny market. Innovation is almost impossible; the cost of getting products to market is prohibitive. PCA's chief executive, Steve Hodgson.
"It's a perfect storm: very few products available, and very few people willing to invest in what's actually a tiny market. Innovation is almost impossible; the cost of getting products to market is prohibitive. PCA's chief executive, Steve Hodgson.

The revised standard also sets out the current consensus that, when it comes to tackling damp-related infestations, the best course of action is to locate and eliminate the source of damp and allow the structure to dry out. “More people are now aware of the issues,” comments Edwards. “We are reinstating the knowledge we had generations ago – before the invention of the damp-meter.”

This process of re-education that Edwards describes has been going on for the past 20 or even 30 years, but has recently gained momentum with more people becoming aware of the problems caused by combining modern materials, such as cement renders and polymer coatings, with traditional structures.

So too have people started to question the use of modern chemical treatments for age-old problems such as insect attack and fungal growth.

In the preface to his 1999 book Timber Decay in Buildings – widely regarded by conservationists as the Bible of timber preservation – Dr Brian Ridout, a consultant specialising in the subject, wrote: “Pesticides may be used in a ‘safe manner’ and this is the province of the remedial company, but legislation is continuously evolving and pesticides are becoming increasingly unpopular.”

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And he added: “Ten or twenty deathwatch beetles distributed around a sixteenth century house does not mean that the building will be destroyed, but any attempt to expose and treat all of the timbers might. The beetles may have been present for centuries, damage will be very slow and removing sources of moisture might ultimately resolve the problem whilst leaving the building intact.”

In the same year, the BRE’s Dr Janice Carey and Colin Grant wrote in The Building Conservation Directory: “Decay will cease if the moisture content of the wood is reduced to below about 20%...Liquid preservatives can be applied to the surface of sound timbers left in situ to help prevent new infections developing during the drying process. However they should not be used or regarded as an alternative to physical methods of protection”.

At which point, cue Peter Ward, for whom such concilliatory language is mere prevarication. Ward, a geochemist and historic buildings consultant with Shropshire-based Heritage Consulting, believes that chemical treatments are nothing less than a con: “The industry started in, I believe, 1962, when some wallies started playing with these new damp-meters and discovered a new way of ripping people off,” he declares.

Pete Ward
Pete Ward

The self-appointed nemesis of the PCA, Ward describes himself on Twitter as “Geologist, Miner, Destroyer of Damp Companies and Old House expert…” The damp-proofing industry, he says, is “completely corrupt and largely incompetent”; the PCA and its member companies are simply fraudsters.

Sections from an oak sill beam from ta 17th-century timber frame that had been injected with timber treatmet chemicals.
Sections from an oak sill beam from ta 17th-century timber frame that had been injected with timber treatmet chemicals.

A contractor has drilled into the beam, injected biocidal chemicals and plugged the holes although the timber into which the chemicals were injected is sound.
A contractor has drilled into the beam, injected biocidal chemicals and plugged the holes although the timber into which the chemicals were injected is sound.

Ward relishes every opportunity to goad the PCA – and anybody associated with it – using the most colourful language. But he reserves special scorn for those who he believes should know better than to lend credibility to the association – such as chartered surveyors.

“This is where the whole thing goes skew-whiff: you’re looking to buy an old house and the surveyor comes along and, to cover his arse, says you should get in a PCA-registered damp-proof specialist to have a look at it,” says Ward.

He adds: “The damp wally comes along with his damp-meter and says ‘you’ve got damp’ and quotes you thousands of pounds to put it right.

“It’s a fraud. As a surveyor you have a responsibility to understand the effects of damp on a building. If you don’t understand it, you shouldn’t even be surveying a doll’s house.”

His view is shared, though expressed rather differently, by John Edwards: “It’s unfortunate that valuers don’t recommend proper surveys but so often recommend the services of a damp-proofing company,” he says. “I don’t understand why the issue should be delegated to the PCA, but I’ve been told by at least one surveyor that it’s ‘in the template’.”

Ward gleefully reports that his vigorous campaigning is gaining traction. “RICS have had enough lambasting from me and now they are finally waking up to the problem. But they’re a long way behind. The CIOB is much more aware of all this stuff; their members are far more enlightened,” he says.

Mortgage lenders are also waking up, he says. “They’re getting pissed off with this. They reckon that 30% – 40% of sales of older properties are falling over because of it.

“The damp-proof companies have destroyed thousands of buildings and cost people millions of pounds. I tell you, this is the next PPI scandal; soon the truth will be out and then the banks and mortgage lenders are going to go ‘oh fuck...’”

The mere mention of Ward’s name provokes a furious response from the PCA’s Steve Hodgson, who is quite prepared to give as good as he gets, calling Ward “ignorant”, “uneducated” and describing him as an “ill-informed, disreputable chancer”. As for Ward’s accusations of fraudulent behaviour, Hodgson says: “If he had any money I’d sue him.”

Ward – not surprisingly – counters that he’s never been sued only because he can prove he’s right.

Hodgson will admit that Ward is right only on the matter of dry rot: “I would completely agree with him. But if you look at our code of practice – which I don’t suppose he ever has – we absolutely do not advocate the use of masonry biocides,” he says.

On every other matter, Hodgson is in completed opposition. He rejects outright the accusation that he’s simply in the business of selling chemicals. “I would be absolutely livid if you wrote that,” he told TCI. “The truth could not be further from that statement.

“For most of our 300 contractor members, timber preservation is only about 4% - 5% of their annual turnover,” continues Hodgson (a claim that provokes howls of derision from Ward). He continues: “The market in preservation chemicals is tiny – worth only a couple of million a year. Our members provide a wide range of different services into damp control in buildings.”

Then, in apparent contradiction of the PCA’s August announcement, he adds: “As CEO of the PCA I can tell you that if we didn’t have any access to these chemicals it would actually improve our business. I wouldn’t be surprised if one day these products were no longer available to us. But one thing I can say is that wood-boring beetles won’t go away. The problem will still be there, so what are we going to do about it?

“We’ll find a way, but it will cost more money and will take longer.”

This article was first published in the November 2018 issue of The Construction Index magazine

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