UKC

I have a Victorian/Edwardian house.The walls are made of solid granite skins filled with rubble. It was built without a damp-proof course (but has an electro-osmotic one which seems to be doing the job). With the current prolonged wet weather the water table is 4" above the bottom of the voids under my dining room floor i.e. there is a lake under the house. I'm currently replacing the dining room floor and am fairly certain I'll have to do the lounge and hall as well (dry rot & woodworm in the dining room one) along with various bits of window frame. I feel a moisture meter would be a very good purchase for me, are there any surveyors on here who could recommend a particular brand or model? I appreciate that the readings are not necessarily absolutely accurate, but it will help me tell if things are getting damper or drier. I'm thinking of one with pin probes, and have seen one with a remote probe recommended on a US site (which sounds like sensible advice to me).

In reply to Toerag: From what I read before we purchased our 110 yr old gatehouse, damp meters are the preserve of charlatans trying to sell you unnecessary damp proof remedies like the one you already have which for the most part don't actually work. I wouldn't bother the expense.

In reply to higherclimbingwales:

Absolute rubbish. I'm a damp proofing contractor. I offer complete guarantees with all my work. The solution I use varies on what the damp problem is.

More often than not cowboys will say it needs a damp proof course of some sort, when all that's happening is the property isn't getting enough ventilation and black mould forms on cold wet areas.

You sound like you have been done over by a cowboy in the past. Don't paint everyone with the same brush. You obviously have no idea what your talking about.

Properties don't need to be wet and damp, trust me mine isn't. And yours shouldn't be either.

To the OP I will send you some recemendations

In reply to xplorer: didn't get done over by one but we got a quote by a firm for the whole house and they quoted silly money for a cavity drainage system on an above ground room and DPC injections in a rubble wall etc etc. We have forgone all treatments and 'remedies' and we've got no damp anywhere and most of the inside house is either level with or just below ground level outside.

In reply to xplorer:
>

Do you do chemical injection damp proof course work?

In reply to higherclimbingwales:

So your one bad experience means no damp proof system works. I've got hundreds of previous customers who would quite happily tell you otherwise.

Like I said everything damp problem is different and gets treated differently.

Do you work in the building trade.......? Obviously not

In reply to blurty:

I use various different solutions. Silicon based mortar injection is one option. But I wouldn't used just that as a defence. Inserting 2 perp vents per linear metre. Using anti fungal treatments. And waterproofing agents in substrates

In reply to xplorer:

I'm not sure what 'silicon based mortar injection' is but it I'm afraid I'm dubious

(Chartered surveyor, 30 yrs experience)

Convince me

In reply to blurty:

What's there to be dubious about. My product comes with a 30 year guarantee!

People love to pretend damp isn't a problem, it really is. It damages brick, timber, plaster and your health if left.

What experiences have you had with damp in your line of work. Have you ever solved a damp problem.

In reply to xplorer:

I've solved lots of damp problems, I've fixed gutters & down-pipes, tanked basements, dug paths away from the sides of buildings, unblocked airbricks, fitted ventilators to eaves and ridges, etc etc etc.

I've never fitted a chemical injection DPC though.

Sorry

In reply to xplorer:

To be frank, none of those would help the OP.

In reply to blurty:

Chemical dpc isn't always the solution. And is never used as the only fix.

Out of maybe 600 jobs I've done I've only used a chemical dpc on about 50 of them.

It's not the installing of a dpc that costs a lot, it's a small part of the job. The treatment or removal of substrates, rendering, plastering, painting etc etc is what bump the costs up.

In 10 years of doing damp work I've never had any customers that have used my 30 year guarantee.

And trust me I've seen plenty of dpc's that needed replacing because they have failed, brick work completely destroyed, piss wet through, I know for fact the amount of water I've witnessed wasn't just condensation.

Just really don't get why you have something against chemical dpc and damp proof contractors. There's plenty of cowboys around in every trade. That's just life.

In reply to Fraser:

To be Fraser, did I ever say they would. The op asked for moister meter advice. Not for a solution to the water problem.

In reply to blurty:

A chartered surveyor, who digs, and gets on ladders.

Your getting confused, your a labourer by the sounds of it

In reply to xplorer:

I didn't say you did say it. Just that those solutions wouldn't help the OP

Knowing me - knowing you, aha....

In reply to Fraser:

The op doesn't want damp proof help. So I didn't give him any help. My comments are directed at the people who think all damp contractors are rip off merchants.

Rite now you need 2 positives, one to cancel out the negative and one..... Just so I can have a positive........

In reply to xplorer:

Only one person vaguely said that. The other seemed doubtful of the ability of a silicon based injection to prevent damp.

Why so chippy?

In reply to JH74:

It's a common occurrence on UKC.

Have you any advice on moisture meters for the op....... No. Why would you comment then. Your just another Climber wannabe looking for a fight.

In reply to xplorer:

That answered my question nicely, thanks.

To the OP you can hire them from HSS and presumably other outlets.

In reply to JH74:

Question? Hmmmmmmm......

In reply to JH74:

Don't hire one, will cost a hell of a lot over a few months. The op wants to monitor the situation not do one check.

Buy a Stanley one. Cheap and cheerful will do the job nicely

In reply to Toerag:

'Moisture meters' (with pin electrodes) are generally used for measuring the moisture content of timber; they are very inaccurate though and not suitable to measure moisture content of brickwork, plaster etc. A hygrometer would be a better bet, but what are you trying to achieve? They are a specialist instrument that are quite tricky to use. They would help in identifying the source of the water, if it's coming in from one direction rather than just as a result of a general rise in the water table.(Which would be a bummer to deal with to be honest)

If there is standing water under a suspended timber floor then there is a significant drainage problem to be dealt with. I presume that where you have replaced floor already, you have laid a solid concrete slab in lieu of a timber floor?

Email me if you want specific advice anyway

In reply to Toerag:

A hygrometer is no use. How would you find the entry point with one?????

Sounds to me you could tank out the underfloor space and use a pump to release any build up of water

In reply to xplorer:

Not sure who exactly that was directed at but I for one wasn't looking for a fight. You're quite right, there are good and bad folk in every trade, particularly when it comes to the construction industry however. I've been involved in it for the last 30 years and know a reasonable amount about damp proofing etc. I attended a CPD presentation by RIW only last week as it happens, but that's of little interest to the OP.

In reply to Fraser:

Wasn't directed at you. As you can see from the post, it was a reply to JH74.

Oh and I'm really pleased for you, thanks for that

In reply to xplorer:


You can use them to pinpoint pipe leaks buried in walls, punctured DPMs etc. (use them like a transceiver to zero in on the wettest area). In the OP's case you could measure which is the 'wettest' end of the floor void, to try and establish the source of the ingress (Broken drain? blocked swale? etc)

I'm really not trying to be clever

In reply to blurty:

I wouldn't worry about master xplorer - for some reason the guy sent me a childish, abusive personal email. I think he must have a rather damp chip on his shoulder. Let's hope it dries up.

In reply to Fraser: From what I've read of his posts that doesn't surprise me. He is one angry young pup!

In reply to blurty:

I'm trying to work out if remedial works I do actually make a difference. For example, I have a completely rotten (and now removed) windowsill on the first floor (west gable) This is definitely allowing rain into the fabric of the wall. I have bare brick chimneys without lead trays that will be doing the same, and parapets without lead on them also. I'm interested to know what the moisture content of the walls are before and after I do things to remedy those obvious faults. There is remarkably little evidence of damp in the house other than phenomenal efflorescence from bare lime plaster where we took a chimney out of the kitchen last year (this has now stopped as the wall has dried out), and an equally phenomenal heating bill.


No- I am currently removing and burning the floor as the boards were rotten wherever they had touched the walls, and all the joists were so riddled with woodworm that they’re crushing under the weight of the floor. I don’t intend to lay a concrete slab as a) it will be cold b)I’m pretty sure I won’t be able to keep the damp out of it and c)it’s a listed building whose character I wish to keep. The existing floor has lasted 100 years or so without proper damp or rot-proofing, so I’m fairly certain a new floor made with treated timbers resting on DPC, painted with bituminous paint and insulated underneath with kingspan will easily last another 100 years.
Unfortunately there are no rainwater drains in the road I can pipe a drain to, nor is there any lower lying land. A soakaway is not the answer as water will simply come back up any drains as the water table rises. As there is effectively no way I can fight the water table I intend to dig the dirt out of the void (which retains moisture even when the water table is low) and re-fill it with lumps of granite to a level above the ‘high tide mark’. This will lower the effective ground level and reduce dampness in the walls in summer whilst also reducing the free surface area of water in winter when the water table is high.

In reply to Toerag:
>> I don’t intend to lay a concrete slab as a) it will be cold b)I’m pretty sure I won’t be able to keep the damp out of it and c)it’s a listed building whose character I wish to keep.

Replacing the floor is likely to come under building control (I think if you are replacing more than 25%, as you have to make improvements thermal efficiency). So BC could be a good source of initial advice.

It may be necessary to have new "oversight" concrete under a suspended timber floor, anyway. Fitting new joists into old (damp) walls presents some challenges. The full concrete slab option may be easier and better performing - for this you'd be well advised to have a qualified surveyor to look at the property and provide an appropriate scheme/drawings. I believe you need to consider the impact to the whole house and how you heat it/ventilate it/let it breath. A slab would be insulated underneath (e.g. with Kingspan or the Leca fill beads).

I've just "kingspanned" suspended floors in a renovation. It is much harder than you first imagine and took 5 times longer than I thought, especially accommodating pipework and electrics. It is too difficult to re-use floorboards and new pine T&G boards would be very expensive.

In reply to JH74:

Not angry. Just may come across like that on the screen.

You offered no advice, which you couldn't through your lack of experiance. Don't take offence to that.

In reply to Toerag:

Protimeter make some of the best damp meters and I used them over a 45 year career as a chartered surveyor. They are very useful if used correctly, but they are only a tool and no substitute for experience. It's absolutely critical that you read and absorb the intruction manual that comes with it, and regularly re-calibrate it. Most are designed for getting accurate readings in timber (which is what I think you are looking for), but other than indicate the presence of damp in other materials such as plaster, brick or stonework, a meter designed to give timber readings won't give you accurate readings in non timber materials. Nor will a simple meter distinguish between rising damp, penetrating damp, condensation, hygroscopic salts, plumbing leaks, cat pee, mouse pee*, residual damp, etc that's where the experience and competence of the surveyor will come into play. Very often dampness is not caused by just one factor, but by a variety of factors.

*You might snigger but one of the most bizarre cases I was involved in was when a client called me in to advise on damp staining on the plaserboard ceilings. He had been told by a cowboy roofing contractor to recover the roof because the 1970's Redland 49 concrete tiles "had become porous". I found a number of holes in the insulation material which let to tunnels running through and under it. On peeling the insulation back I discovered a "mouse city" Dozens of them which had been peeing at specific points over the ceilings to the extent that it had soaked through, and was giving high readings on the moisture meter.

There are some very reputable damp proofing contractors (no doubt including some who have responded to your thread, out there but generally they don't offer any better service than an experienced and reputable builder who knows what they are doiung. Unfortunately in my experience there are also a lot of incompetant so called damp proofing specialists and mis-diagnosis of damp problems is common. I've seen expensive dpc's installed when in reality all that was needed was gutter improvements or repairs! Where the dampness is a result of a variety of causes they may overlap and mask each other, so tracking down the main causes of damp is often time consuming and can involve tackling the most obvious causes first to see if that cures it before falling back onto other probabilities if it doesn't.