Damp meters should be banned!

[@hhguitars]

No meaningless. They're calibrated for wood.

[@WarmDryHome]

Agree - Even protimeter say they cant be used in anything other than wood. The conversion tables are for different species of wood - and sampling must be done at strictly controlled temp and RH conditions. They are useless for anything other than clean, freshly felled timber of known species.

[@freedomfighter84]

I have used these old yellow Protometers, i think the issue with resistance meters are only good for internal building materials snd should be used with a great amount of common sense and understanding of building materials natural moisture contents. They can easily give false readings especially with dense materials and salt contamination or if wall has cables or metal. The best way to use them is to compare area of concern to other area of same material and if the difference is great then why?

[@whitacrebespoke]

As a carpenter and saw miller I won't use one of these probe type moisture meters as they are so inherently in accurate

[@WarmDryHome]

Thanks Adam - good to see a professional in the field saying the same - and that's about a piece of kit designed for fresh new wood. They include correction tables when you buy it - you are supposed to correct the reading to the species of timber!!

[@whitacrebespoke]

Peter Ward I saw a video of a damp man the other day saying if you get foil backing make the holes bigger with your pen knife. I did chuckle lots a conductivity metre that goes mad when in contact with foil there's a surprise.

[@whitacrebespoke]

My dad had one for his fire wood and it was not much good for that.

[@WarmDryHome]

I tried mine on the newly felled logs - seems to give a very rough indication - off the scale in softwood most of the time, and in oak / beech seems all over the place. The only reliable thing is when they don't react at all - think you can say it's dry then... :-(

[@gdr1174]

Just had a survey on a Victorian terrace house I want to buy telling me we have damp. It also includes an image of an MMS2 protimeter apparently proving this.... before seeing this video I was worried about the situation. Now I think I'll take it with a slight pinch of salt and have more extensive testing done.

[@lawreence13]

peter . I'm watching all of your videos and so far I get the impression that you are against 'tanking' celler wall? Do I have that right?

[@georgemiles5265]

The Pins are for checking would and calibrated for wood. If using on other materials then you have to use a conversion factor from the manufacturer. Some meters have settings for different materials.

[@WarmDryHome]

Even protimeter say they cant be used in anything other than wood. The conversion tables are for different species of wood - and sampling must be done at strictly controlled temp and RH conditions. They are useless for anything other than clean, freshly felled timber of known species.

[@matthewharding89]

Peter, I love your no nonsense and get to the point assessment of these things! (and surveyors!). Having some trouble in my current home with damp, often visibly wet walls. The house is an 1850's stone terrace house that the previous owner kindly stuck cement render/pebbledash on and gypsum plaster throughout the inside. Suffering terribly with salt deposits inside. I also believe the ground level to be too high at the front and back of the house. Not sure where you are based but I would be very interested in your service and valuable assessment if you covered South Wales? Cheers.

[@WarmDryHome]

If you email [e-mail] we'll see what we can do to help - either myself or I have an associate down there who is brilliant - can try to help with a telephone consult - photos etc - and we could give that a go first.. Sounds like a breathability issue - as always - removing render, lowering ground levels, better internal ventilation, humidity controlled, open fireplaces, swqeep chimneys, remove salty gypsum plaster - you get the general gist of it... ! Have a great Xmas and keep at Sophie - we are shut over xmas and new year for a break - but we'll get back to you... !

[@matthewharding89]

Thank you Peter for taking the time to reply, I'll take some photos when I have the opportunity to do so and I'll get in contact with Sophie. Many thanks again!

[@greyhairedphantom4038]

i use one of those doing SALT damp work. i remove walling that is badly infected by salts, and replace it. i am not looking for a damp height as much as salt impregnation. can you then tell me of a process other than the wally machine, that will give me an accurate measure of the salts present in the building materials? Bear in mind i am in australia where salt infection in some areas are extreme, putting it mildly. i use the "wally" Machine as a secondary to my experience. ie.. if a section of wall is showing no damage at all and reads on the tool my assessment is its fine, maybe high in salt but its not a problem. like you i believe plastic paints, and cement renders and pvc tanking is a fast road to destroying a building. i had an external wall in a client home, cement rendered, that behind the render was in an awful damp and saline state. i removed the render and every month had the owner brush the salts from the wall. 18 months later i replastered. 8 years and the wall shows no sign of deteriation or damp spots. i replaster a couple of houses for the chemical cowboys, and its heartbreaking to see lovely old homes, that originally where built by a cowboy 120 years ago. it has no dampcourse, but more importantly the guy who built it had no idea of underfloor ventilation. by undersetting the walls i can reconstruct the underfloor and ensure good underfloor.

[@WarmDryHome]

Interesting to hear from you - I spent 25 years in Perth and Kalgoorlie mining - so very familiar with Oz conditions. What people don't consider is the often very high humidity and extreme temperature changes in building fabric. You can get 40 degrees and almost 100% humidity in the day, and almost freezing at night. Ideal conditions for a lot of interstitial condensation, water build up in the base of the wall where it is cold, and solution of salts in the rock, brick, and mortar. These then transport to surface when the water tries to evaporate - leaving salt on surface. People try to claim it is all capillary - it's not - the ground is too dry most of the time even if capillary COULD happen, which we never see. I'd be interested to see some proper monitoring of humidity, total moisture (absolute - grams / cubic metre) and temps of the walls (need a thermocouple in the wall logging for a few months) - but I'll guarantee its nothing to do with capillary - and a lot to do with humidity. The hotter and more humid the region, the more salt damp we see. Solution? Much better control of internal conditions - breathable walls, and removal of humid air from the house - AND not allowing the walls to cool down dramatically at night - which is a hard one in Oz, because people don't want heating to kick in just because its cold outside. Did quite a bit of research when I was working with amdel in Adelaide - and was disappointed to see the bulldust spouted by the SA govt research into salt damp - the research was badly designed, and did not address any of the internal moisture and temp issues - they never even measured temp, RH, and total moisture! They just assumed damp was rising and left it at that - pathetic work. Good luck with your business though - great to hear someone taking a sensible approach to it - you're one of few!!

[@CurvedSlightly]

Hi Peter, I looked at a house yesterday with a problem with the floor, some 'surveyor' or house hunting 'know-it-all' had been in and in a couple of the patches in the wall where there is 'damp' I noticed pin pricks from the dreaded prongs of doom! :)

[@WarmDryHome]

As always! Nobody bothers to take proper humidity measurements - RH, Temp and Absolute - being grams water per cubic metre. Good dry air about 7 g/m3 Damp being over about 9 or 10 g/m3. If air is damp - you'll get condensation in cold spots = damp walls - but they should dry out if breathable - if not, wall gets wet till you take the plaster / cement off - then it dries. Floors the same - airflow does wonders..

[@hamzahassan8676]

Great video. However I don’t think they should be banned at all, these machines are calibrated for use in wood. There is no tool better then sight and smell to identify dampness.

[@annturner4830]

I've just had a survey done on my house and the surveyor used what looked liked the same damp meter . I was told we had rising damp and have now lost my buyer because of this . .my walls are bone dry so I was more than surprised at surveyors report . Just don't know what to believe anymore.

[@WarmDryHome]

We see this every day. It is scandalous. RICS is a big part of the problem for allowing surveyors to use 'damp meters' instead of training them properly. 3 British standards say they cannot be used. BS 7913, 5250 and 6576 all say chemical methods are the only way.

[@WarmDryHome]

***** Injections dont stop anything... No such thing as rising damp. And no - the guarantee isn't worth the paper its written on - make a claim - they laugh at you and say "dear - we cured the rising damp... this isnt rising any more - oh no - this is condensation and thats not covered" Standard industry trick - massive con. And you pay for it - about a fiver - they get the money for the guarantee - its paid out of the profits of the Guarantee Protection insurance fund that is shared out to the damp proofer members of the PCAevery year. As for PROPER diagnosis - two ways to do it - we can do surveys on every house and show you what to do and how, and why - or we could arrange seminars to teach you. Have you ever thouoght that if all this stuff worked, the problem would have gone by now - half these houses have been injected about four times. It is all about moisture - mostly produced by inhabitants. Most common cause - lack of ventilation. Then high ground levels, broken drains (as in your house with sub floor with water) and so on. There is ALWAYS a credible, sensible diagnosis and solution. It NEVER involves damp proofing. Your best friend should be a thermo hygrometer - measure humidity and temp - understand what absolute moisture content is all about - its simple. Look on the www.heritage-house.org website. Don't EVER use that con artist again - you don't need him. At most, you need RHL humidity control ventilation - google RHL ventilation and ask for Ray Hudson - he is one of the most experienced people in the business - worked for Lewisham Council for years, who have zero damp problems in their housing stock for a very good reason - Ray!

[@greyhairedphantom4038]

i agree - in part with you pete. my experience with salt damp in australia says capillary action causes major damage, if a dampcourse is not present. However simply putting chemicals at the base of a salt infected wall wont fix it. Any plasterer that puts the damp company,s cement render with "salt inhibiter" (an interesting name for a damp proof additive) onto a wall, then guarantees it is a complete idiot! i like to sleep at night, not worrying about tome bombs like the Chemical Cowboys hit us tradies with!

[@WarmDryHome]

You are anything but a 'tradie' if you have the attitude you have - you are questioning, observing, and looking for real solutions to problems you are trying to understand - you're a rare breed! I'd just be careful about the capillary bit - unless you can see it in action - dont assume capillary - its very rare to almost non existent. Look at the temp / RH stuff first - diffusion of water through the material yes - not capillary. Diffusion acts in all directions - but remember - water molecules as a gas are lighter than oxygen and nitrogen - so when air is diffusing through a wall, the water molecules WILL rise - not by capillary, but by simple diffusion. Understand that, and you have a chance to see things differently - if you cool a wall with water gas diffusing through it, as it cools below the dew point - usually at night - the water molecules condense as liquid water - a bit like fog forming in the wall. THAT's when the problems start. Trap that condensed water, and you then start dissolving salts in the bricks / mortar / stone.. As it evaporates - bingo - salt damp. Get the condensation under control, and you stop the salt damage.

[@greyhairedphantom4038]

Peter Ward over the many years of undersetting stone homes one thing has stood out to me. the houses with no dampcourse where generally in a terrible state, with every wall infected. homes nwith dampcourse i found that i could find a reason that the dampcourse failed. things like dampcourse bridged by concrete veranda floors or render. An interesting aside, my experience rendering injection work. i took the Protimeter and tested all the walls i had rendered for them some two years after i completed. it registered off the scale on every wall. i mentioned this to the chemical expert and was told that was always the case. this ofcourse is true, as the protimeter is just registering on the salt content in the wall. this particular home is one i would love to tell you about one day, chemical damp proofers are wallys mate, totally!. by the end of my work there, the owner said she wished she had contacted me and not a Chemical Cowboy.

[@joshbreeze5896]

The Protimeter is primarily designed for timber and plywood, however can be used on other materials but to be read with caution. The Caravan industry uses these and are NCC approved as the design of them are for timber and wood. for building I'm not sure, it may be worth speaking to Protimeter themselves for direction.

[@WarmDryHome]

Even protimeter say they cant be used in anything other than wood. The conversion tables are for different species of wood - and sampling must be done at strictly controlled temp and RH conditions. They are useless for anything other than clean, freshly felled timber of known species.