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BBC's 'Raising the Roof: January 1999'

Having posted a review of BBC's 'Raising the Roof' 2000, I thought it might be useful to show what variation was obtained in their 'Raising the Roof' relating to damp proofing shown in January 1999.

The basis of the programme was that dampness within a particular property in Birmingham was not attributed to rising dampness, but to anything but rising damp. The house was set up so that a number of specialist damp-proofing surveyors looked at the building and gave their opinion. Yes 9 out of the 10 diagnosed rising damp. The programme then went on to show they were wrong - but they weren't!!

In essence, the BBC originally called in one, Mike Parrett, but after some concern about his technical findings based on his analytical methods, the BBC then called in Dr Singh and Birmingham City Laboratories. Unfortunately, the BBC didn't feel it necessary to discuss on the programme the partly objective laboratory results (and even these weren't complete!) from Birmingham City Laboratories, probably because they showed active long term rising dampness! So, based on the following make a judgment for yourselves.


The Parrett Report:

This report still formed the basis of a large proportion of the programme ie, that rising dampness was not present within the property inspected. All his tests were using on-site, mostly superficial methods. This is some of what he described in his report:

Mike Parrett: "The internal leaf brick work was a benchmark at 0.4% in the state of dryness"

Comment: How did he form his 'benchmark'? Guesswork? There is no data provided.

Mike Parrett: "Vertical moisture profiles were undertaken which were not consistent with that of rising damp."

Comment: Now this is fundamental to the whole argument relating to the programme. Indeed it was the programme's 'raison d'etre'! Yet Mr Parrett gives us this simple one liner - no figures, nothing! These results should be absolutely crucial!

A single moisture profile, if undertaken properly, should consist of 5-8 samples. If this was done with a 'Speedy' meter as used by Mr Parrett then each profile should take over an hour if it is done in accordance with the instrument's instructions - and he said profiles. We believe that he didn't take anything like the number of samples required. And, again, as this is so fundamental to the plot, where are his figures?

Birmingham City Laboratories did carry out some very basic profiling, although not complete, which using some assumptions they had to make, clearly showed such profiles to be consistent with water rising from the base of the wall. These, together with their soluble salt analyses, again clearly showed there was active rising damp in parts of the property.

Mike Parrett: "Several core samples of brick wall were extracted by "cold drill method" and tested for actual moisture content using the calcium carbide test, the highest reading obtained was 3.8% near to the base of the inner leaf of the front bay."

Comment: Interesting. Birmingham City Laboratories give much higher figures. But this time Mr Parrett actually quotes one of the figures, unlike the comment about the moisture profile. So, again, where is the moisture profile data? If he can quote a relative insignificant figure like this then surely moisture profile data should have been provided. One must now clearly ask the question did he actually undertake a moisture profile?

Mike Parrett: "BRE Digest 245 states that moisture content in brick walls below 5% is unlikely to be rising damp."

Comment: No it does not state that at all! (see '5% moisture in walls - is it dry?'). Mr Parrett should actually read and understand the Digest and not make statements which are badly misquoted or, indeed, which it does not contain!

Mike Parrett: "Salts tests were undertaken at a number of locations to internal and external walls within the dwelling, no nitrate ions were detected, low concentrations of chloride could be detected using the on site test."

Comment: Birmingham City Laboratories found several locations of high chloride and nitrate concentrations, completely opposite to these apparent findings by Mr Parrett. This basically reflects the superficial nature of on-site testing, and indeed having sufficient expertise to know where to sample in the first place. If Mr Parrett missed the salts or failed to find them, then this would clearly flaw his diagnosis - which it did.

Interestingly enough, whilst Birmingham City Laboratories did find ground water salts (soluble chloride and nitrate) in concentrations up to 780 mm above floor level in a number of areas, they conveniently forgot to mention how they got there! One thing is certain, they did not get to that height by simple 'bridging' as is claimed in one of the reports used for the programme.

Mike Parrett: "Evidence of a water leak from either the bath and or the water storage tank mounted on a raised platform within a walk in cupboard within the kitchen was evident by water staining, lifting of the wallpaper and heavy presence of efflorescent salts to the internal wall within the cupboard, which when tested revealed a near normal moisture content of 0.5% from the brickwork and a weak trace of chloride."

Comment: Birmingham City Laboratories found the total moisture content of nearly 6% against the airing cupboard wall, and high concentrations of chloride and nitrate up to 520 mm - not exactly what Mr Parrett reported!


Note the often completely contradictory results between two experts yet we get the same conclusion - and this was wrong! Now, having seen the above, does one believe in conspiracy theories?

Perhaps the conclusion that there was no rising damp might have been expected; after all, one of the experts has publically stated that he has never seen true rising damp in over 20 years - if he's not expecting to see it he probably couldn't even if it jumped out at him! - nothing like an open objective mind to make evaluations!

One can only suggest that this 'Raising the Roof', like the most recent version, had a specific agenda and nothing was going to change it! This appeared to have been fuelled by the data (or lack of it) from Mike Parrett. And like the most recent version of 'Raising the Roof', there has been no right of redress!


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