Damp check on Alu-tech Caravan

[Kai]

Hi! I have checked damp on alu-tech Bailey caravan with my moisture meter (10-20£). When I checked from outside, most of body show 100% damp, but rear pillars 0%. From inside, in the same locations, it is 0%. On the floor, 35% near toilet and front table, on further places, near 0%. I wonder if the moisture meters work on outer alu or GRP materials. I don't know how far 35% is from the professional check results. The rear outside right corner plastic has a filled crack, is that why toilet floor damp? Is this serious problem? The seller have serviced and damp checked every year from new. The last month's check doesn't show any percentage or damp comments, but one or two damp reports under 15% seven years back. The caravan looks good condition. Should I believe caravan service reports?

 

[otherclive]

Moisture meters don’t work on metals as they are impervious to moisture. So the 100% on the outside is meaningless. You only check inside. Grp will not give a meaningful reading either. 15% six years back is not relevant to today. If last months check had no damp readings ask the seller to have a damp survey carried out or walk away.

 

[Kai]

Moisture meters don’t work on metals as they are impervious to moisture. So the 100% on the outside is meaningless. You only check inside. Grp will not give a meaningful reading either. 15% six years back is not relevant to today. If last months check had no damp readings ask the seller to have a damp survey carried out or walk away.

The latest damp report shows click marks with no reading on floor/ceiling diagram and on the diagrams of all sides just show "visual". I suspect the service man is one-person company at home address. I am satisfied with the caravan condition for price, no mouldy smell. I wonder if it is easy and inexpensive to replace or fill cracked plastic with sealant. If that fixes dump at toilet, it is worth of consideration.

 

[otherclive]

The latest damp report shows click marks with no reading on floor/ceiling diagram and on the diagrams of all sides just show "visual". I suspect the service man is one-person company at home address. I am satisfied with the caravan condition for price, no mouldy smell. I wonder if it is easy and inexpensive to replace or fill cracked plastic with sealant. If that fixes dump at toilet, it is worth of consideration.

Even a one man service company should be able to carry out competent damp checks. My AWS technician was a one man company. If your didn’t do a proper damp check I’d have to ask what other aspects were not carried out properly.

I’ve had caravans that had damp with no noticeable smell. Often a musty smell comes from inadequate ventilation. If you can smell damp it’s a bigger problem.

Given you have 35% in two places my first action would be to have an AWS damp survey as the tech should be able to give advice on where it is coming from and how to deal with it.

 

[ProfJohnL]

If you have a soggy floor, then I suggest avoid the caravan. Bailey caravans have a recent reputation for developing soggy floor corners, and until the damage has been exposed you have no idea how far the problem has propagated, or how much it will cost to put right.

 

[Mr Plodd]

Basically you cannot check clutch panels fir damp, because they don't have any timber in them. The only place there is timber is the two surfaces of tge flooring.

 

[Kai]

Basically you cannot check clutch panels fir damp, because they don't have any timber in them. The only place there is timber is the two surfaces of tge flooring.

Yes, I checked damp on other caravans of a dealer today, I found the moisture meter has high reading on metal frame of window and 0 reading on inner plastic. A same model of Bailey Alu-tech has 25% reading near double bed. The dealer said all of their caravans are damp free and my meter is not good. I agree it may not be accurate as their professional one. but it can detect difference between damp and dry floor.

 

[Kai]

Even a one man service company should be able to carry out competent damp checks. My AWS technician was a one man company. If your didn’t do a proper damp check I’d have to ask what other aspects were not carried out properly.

I’ve had caravans that had damp with no noticeable smell. Often a musty smell comes from inadequate ventilation. If you can smell damp it’s a bigger problem.

Given you have 35% in two places my first action would be to have an AWS damp survey as the tech should be able to give advice on where it is coming from and how to deal with it.

I don't doubt one-person company's competency, I just wonder he may want to keep his customer happy with check results.

 

[otherclive]

I don't doubt one-person company's competency, I just wonder he may want to keep his customer happy with check results.

If he were to falsify the damp test results then he misses out on potential follow on work. Or are you saying he reports zero damp to help the owner sell the caravan.

 

[IanB1485]

As others have said damp readings are meaningless on the Alutech walls and roof , thats why only a visual inspection is undertaken , main areas are around window and rooflights and the two roof straps which join the roof to the front and rear panels.- PS I deplore 'ticks' on a form. The floor is the only place where wood is used .Often moisture will get trapped between the floor and the vinyl floor covering, Unfortunately to remove it will require cutting it at strategic places as its fitted to floor before any furniture is fitted . Also some vinyl floor coverings show up as 'damp' as the underside is porous, The trick is to establish a 'norm' value for the floor and look for discrepancies i.e gradual increases in readings, rather than individual high readings I have both a pinned one and an ultrasonic one I us the ultrasonic one on floors as its easy to watch the readings increase as the unit is moved over the floor , Isolated high reading are usually caused by staples or other metallic items used in the initial construction or if a repair has been made. I also look underneath at the corners as these can be good indicators all is not well.

 

[ProfJohnL]

Sadly this is another thread where a caravanner has a piece of test equipment but does not know how to use it , and thus could be getting erroneous results leading to unsafe conclusions, and thus concerns which may or may not be true.

You need to understand the different construction methods to know if you can use a resistive moisture meter, and then how to make sure your not compromising the reading by using the meter on unsuitable materials. Or how to interpret the readings you do get, as different materials will have a resistive moisture content and be perfectly satisfactory.

Often the cheap meters do not come with sufficiently detailed instructions, and of course there can also most will not be supplied with a proper calibration certificate to allow the user to know what sort of error the instrument may have.

 

[Kai]

Yes I understood the alu-tech roof and sides have no damp issue for no timer inside it. But when I checked the floor near toilet, the meter had high reading, then moved it out away, it became zero. I saw someone posted damp report, it has readings on diagram. I don't know why some damp reports have no reading at all but ticks.

 

[RogerL]

I thought there were two types of damp meter - the "traditional" 2-prong type which can be used on wood or brick (not the latter in a caravan!) and the newer 2-pad type which is specifically intended for impervious surfaces like GRP and used by AWS technicians.

I have a 2-prong Protimeter - but then I have a conventionally built caravan with interior plywood surfaces.

 

[Mr Plodd]

Mine is a pronged version, Alu-tech Bailey caravan so just used on the floor. The prongs don't leave visible marks in the flooring.

 

[Hutch]

Mine was the two pronged type for checking the interior walls of our Coachman, thankfully our reading always matched the AWS techs readings, all nice and below 15 %.
Unfortunately and how ironic, the meter got damp in it, and has gone into the skip.

 

[Kai]

Mine is pinless with four modes drywall/masonry/softwood/hardwood, it doesn't damage surface. I checked the hardwood floor in my dining area, it is under 15%, but higher reading on vinyl in cooking area.