Technical twaddle taken from Damp websites...

Example 1: A 'Major National Company!'

Rising damp is usually found by the signs of a damp line appearing on the inside wall. This is often combined with damage to skirting board and decorations.

The result of this rising damp is structural damage to interior render- plaster systems. It should also be noted that recent findings by the asthma foundation concluded that damp rooms can increase the risk of developing asthma. Rising damp occurs when ground water is allowed to rise vertically through walls by capillary action and is caused by the breakdown of, bridging of, or non existence of, a damp proof course (DPC). Thus the dampness is rising through the actual mortar beds rather than through the brickwork itself. 

Really?  See how they make statements that you just believe - they say it, they must know more about it than you - so you just believe this rubbish ... read on....

If left unchecked it will rot any floor joists and other interior timber it comes into contact with, culminating in the development of wet rot or dry rot if conditions of lack of ventilation allow.

The following will contribute and develop rising dampness in buildings:

  • Blocked or defective rain water goods (guttering).
  • High ground levels, new drive ways, paths or tarmac bridging the DPC.
  • Defective pointing, porous brickwork, spauling bricks.   
  • Faulty or defective flashing on roofs or extensions.
  • Cracked or Missing roof tiles or slates.
  • Internal defects in cavity walls.
  • Cracked or Defective window sills.
  • Internal chimney defects- where a fireplace has been blocked in.  

None of these bullet pointed things are anything to do with rising damp.. Collectively, they are problems associated with penetrating damp, high ground levels, cement render and pointing, and bad roofing.  All of these problems should be individually diagnosed and are nothing to do with rising damp.  None are expensive to sort out, and come under normal building maintenance.

Rising Damp along with all damp problems is a health risk. We recommend that a survey is carried out immediately if any damp problem is suspected.

Wow!  So now we're trying to scare you with health risks - careful - the damp man might threaten you with an iron bar if you dont sign the contract after his 5 minute 'survey' reveals the damp course has broken down - probably for a third or fourth time....

Example 2: More Damp Company website fun...

Our findings are based upon visual or instrumental evidence as recorded in your report.  Regarding damp problems, unless it can be specifically diagnosed as condensatory, we have presumed that “damp” readings are due to the lack of a damp-proof barrier.  

Woo Hoo!  We admit that we 'presume' theres no dpc.  Wheres the diagnosis you idiots!

This is not intended to infer that any previous works carried out by others is at fault.  All initial checks for damp related problems are conducted with the use of a simple pin type moisture meter.  We do not, unless otherwise requested in writing, carry out damp surveys using carbide meters which require samples to be taken physically from the brickwork by drilling.

Oh great - so we use inappropriate equipment to persuade you theres damp where there isnt any...  we even admit that the ping prong meter doesnt work, and we should be doing carbide tests (which nobody does anyway) to try and prove the wall really is wet..

And these are the 'technical' specifications of the company... :-)

1.  First Rendering Coat

 Mix:  Three parts washed sharp sand to one part sulphate resistant cement.

And now for the chemical warfare:

 Apply render up to 10mm thick, incorporating waterproofing admixture, using only sufficient water to maintain workability.  Water to be free from contaminants, the cement should be fresh and free flowing.  Do not over trowel. On initial set, scratch to provide a mechanical key and apply floating coat before the scratch coat has finally gone off.

Leave a 25mm channel between the rendering coat and any solid floor.

OK - my bold and italics here - waterproofing folks - waterproofing.... So we've just slapped waterproof crap on the wall - er.... how the hell is it supposed to dry out - please read on.....

2.  Second Rendering Coat

 Mix:  Four parts washed sharp sand to one part sulphate resistant cement.  

 Apply second coat up to 10mm thick, using only sufficient water to maintain workability.  Do not over trowel.

It must be remembered that, even after the insertion of a damp-proofing course, the moisture already present in the wall can only escape by evaporation.  As a general guide, the drying rate is given as 1 month for every 25mm of wall thickness (BRE Digest 163, ‘Drying out buildings’).  Therefore, 230mm will take approximately 9 months to dry.  However, the drying out depends on conditions, ventilation and the type of masonry, so drying may take  considerably longer.  External finishes, e.g. paint/render, will considerably extend this time period.  Due to the potential prolonged drying of the wall, the following must be considered:

CAN YOU BELIEVE THIS RUBBISH!!! Obviously thousands of unsuspecting folks do - which is why there are still thousands of sopping wet houses all over the country that have been 'damp proofed'!!  Again, my bold italics.  How the hell is the moisture going to get out if the bloody wall is waterproofed.... 

Delay any decoration for at least 4-6 weeks following replastering and allow for good natural ventilation to enhance drying.  After this time period only use a non vinyl based emulsion.  Do not apply heat or accelerated drying methods.

  • Do not use wallpaper, textured wall coatings, oil-based paints or vinyl emulsions for at least 12 months on a standard 230mm wall.  (Longer on thicker walls)
  • Maintain good ventilation around walls.

 Note:  The initial decorations should be regarded as temporary, the final decorations not taking place for at least 12 months after the completion of the damp proofing and ancillary works.


Example 3:

Damp and Condensation
More lovely damp proofing people to check out...

Make sure you read their claims VERY carefully.  Google the addresses in Street View - you'll get a shock... 

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