Damp proof course injection

[Chancer]

Has anyone experience of doing this themselves  who can pass on a few tips to someone with "all the gear and no idea"?

I have a pump, manifold and lances all newly refurbished by myself and working well. I had previously had a devi from a company who stated that due to my old mortar joints they were going to inject into the bricks so initially I followed their lead.

Mine are nine inch thick solid brick walls, I have damp problems on the gable end causing my recent work (repointing and sprayed crepi) to come off up to about one metre high.

Briefly I drilled two holes into each stretcher and one hole into each header above it forming a triangle patter at 100mm centres, the first drilling was at 60mm depth and after treatment was to be followed by two more drillings and treatments at 120 and 180 depths, first thing that i found was that even at 150psi my bricks were resisting the injection and no product was getting through, I later verified this on a test brick in the workshop pressurised at 150psi for 30 minutes which I then cut through to chcek the section the next morning, no penetration at all. However identical bricks laid in one cm of water did suck up the moisture to their full height so perhaps the fluid : http://www.palacechemicals.org.uk/DampProofingProducts.htm is too thixotropic, it is very runny but does form a gellified emulsion when pumped.

Next I tried drilling the stretched courses a bit deeper to fall into the perp behind, big mistake as these not being seen are not well filled, without knowing it all my product found its way through the perps to other side of the wall and flooded my workshop.

Today I try phase II, drilling into the mortar beds as one should, my first drilling at 60mm depth, initially expecting leaks I only pressurised to 2 bar but again no product taken up,no sign of the joint sweating which should indicate saturation. Eventually I pressurised it to 11 bar, 165psi [:-))] and even after one hour the consumption was not measurable, I switched off the pump and left the lances in place with their stop coscks open and the pressure dropped to 80psi and remained so taking nearly an hour to fall to zero.

After lunch I tried the next set of holes after throughly purging all air from all the lances which i did the first time, I injected for 10 minutes, switcehd off and it dropped to 80 psi, I have just gone out to check again, 30 minutes have elapsed and there is still 40psi residual pressure so it looks like whether I inject for 10 minutes or an hour the result, or lack of one is the same.

What was your experience or any ideas please?

As an aside the loacl company wanting €3040 for treating 15 metres of wall had they injected the bricks would have just been going through the motions and hardly have used any product, you pays a lot of money for nowt and a bit of paper claimong to be a 30 year guarantee.

[Wilko]

Chancer why not dig a French drain around the gable end. The only stuff I've heard re injecting chemical damp courses wasn't terribly complementary as to their success at doing what it says on the can.

GL Wilko.

[Théière]

Chance sell the kit to someone else and switch to something that does work.

Silane Cream  several manufacturers and I won't use the old stuff any more

 

[Chancer]

The kit will be sold once used, do you really believe that these creams work? I am very doubtfull, if something as thin as parrafin pressurised at 150psi doesnt penetrate, and in fact I think the whole industry is based around selling a dubious certificate of guarantee, do you really think that a cream put in by a silicone gun will work?

I can see the advantage to the sellers, the traditional fluids being flammable have to be sent by specialised transport which all but precludes mail order and internet sales whereas they can sell one or two 300ml tubes of cream for the same price as a 5 gallon drum of the real product.

Work has ground to a halt for the moment as the membrane in the detendeur (sorry no longer know the English word) has given up under the strain and been degraded by the fluid, now I am on the search for a piece of fibre reinforced viton to make a new one, this area is a centre of hydraulics manufacture but I wish that I were still in England [:(]

I bought the pump and some 250 litres of fluids for a song so should make a good profit at the end.

[Dave&Olive]

Hi ok

 I have done a few to say the least back in the uk on both sand stone and brick.... be it a few years ago now and have only ever used spirit based products . You should only inject into the mortar layer if you have none porous bricks  ,we lived in N Wales and the local brick was Ruabon Reds best method for these was to drill into the brick at a slight angle so as to enter the frog and then inject if you need to inject in to the brick as a stretcher you have to drill in 1/3 then inject and re-drill to 2/3 rds and inject again . For porous brick inject into the brick direct , we used to do a bit of a sales gimmick  we had a London red brick injected with that much silicone we used to drop it into a tank of water and it would float , used to get us  the job no problem .... trouble is with the water based stuff you have to get it right first because try a second time and it`s become water proof so will not take a second coat . we also had some old lances that we fitted bent pipes and funnels too and leave them full over night to do step type damp course............but remember you used to get a 25 year guarantee certificate with every tub of dpc ...   [:)]

                 Dave

[Chancer]

Thanks for that Dave, it does confirm that I am going about it in the right manner, being my own building I am very conscientous its just I wanted to know if I hade missed something obvious.

I can see the logic on injecting into the frog but no frogs on french bricks [:(].

My wall is 230mm thick that is to say a header with a stretcher behind one course, the inverse the next course, the problem is that French maçons dont butter the brick or prepare the frog of mortar (think thats the right phrase) they just splodge down some mortar and plop the brick on it, perp joints dont enter into their world and as for pointing, not me guv! you need to get someone else to do that with an icing bag!

As a result there are huge voids within the wall especially between the headers and stretchers, either the lance seals well and I chuck 150psi at it for 15 minutes with little effect or the pressure drops and the perp void gets filled with fluid which either leaches out elsewhere or dribbles out when the lance is removed.

I am slowly getting there and convinced that I am doing a better job than the local company would, ah buy they give a 30 year guarantee [:P] I also have tons of fluid so that is not a problem.

In the light of what I have said do you have any other tips please? I am at a stop for the moment as the membrane (forgotten the English word) in the pressure regulator has let go rongé by the fluid.

[Théière]

I have had a total success with the creams and if you look around you will find it for a fraction of the price advertised elsewhere. As you are injecting into the mortar and not the brick it does flow nicely along the mortar line and if you get it right you won't need a second application.  As you have found the thin traditional liquid finds voids etc and leaks out everywhere.

[Chancer]

Interesting to hear Théière, how did you judge the success, dampness readings? how long did it take to dry out?

I would have bought the creams but not having had a témoignage like yours and even with the best deal it would have cost a hell of a lot for my long length of 13" solid wall (I am doing the rear of the property as well), it would have been a lot more expensive as I got the pump, lances and 250 liters of product for half the price that a second hand pump alone sells for, plus it has the bonus of being 220v, most are 110 and would not sell in France.

I still cant see how a thick cream (and they made them thicker because the first ones dribbled out) can disperse as well if at all in the mortar however just talking about this has given me an idea (something I really miss with my isolation here) I am going to repeat my brick in water capillary experiment, if it picks up the fluid like the first brick picked up water then I will be secure in the knowledge that the excess product sloshing around in the vides will be absorbed in the mortar course.

Still dont see how the creams can work but they have an agrément certificate but then so does my fluid and I am very sceptical of thats efficacity in anything but carefully staged laboratory conditions, perhaps the cream thins out like fromage blanc, do you have to plug the holes?

Thanks for yours and Daves contribution.

[Salty Sam]

Having used both methods over the years, for me the cream wins every time without question.

You may want to download the following which will answer many of your questions, plus I'd seriously consider you look to page 17 with regard to finishing with a bellmouth casting above the injection points.

[url]http://www.safeguardeurope.com/pdf_datasheets/rising_damp_book.pdf[/url]

This YouTube link gives you an idea about 2 minutes in, how the cream injection works over pressure injection.

[url]http://www.youtube.com/watch?feature=player_embedded&v=hukY_tD5rEI[/url]

[Chancer]

Do you say that based on results Salty Sam or the ease of use?

If I hear from a couple of people like yourself and Théière that it definitely works as well or better than the injection system then I will be persuaded, its just that there is just so much stuff on the net like you linked to and TBH all of it is just like a TV commercial for anti_ageing cream, call me cynical if you like but I would actually like to see some proper, even scientific testing.

Mind you that said it may just reveal that it is 10 times as good as the injection system but still as much use as a chocolate teapot and where would that leave all those with 10, 20, 30 year guarantees?

In any case I have no choice but to continue with the path I have taken, I should have asked for advice a long while back

[Quillan]

I have been following this but I have no experience so nothing to add to the technical side.

However I was just wondering as a side issue about warranty. One assumes (dangerous I know) that if you have a company come and do it you get 10, 20 or even longer guarantee which in the event of selling the property would be passed on to the new owner. How do you stand when you do it yourself? I appreciate that you have no plans to sell up and that this project is your pension but you never know whats round the corner in life.

[Chancer]

Quillan.

I treat the guarantees to be as valuable as any guarantee or insurance here in France, i.e. those foolish enough to purchase them (just my opinion of course) are just setting themselves up for loads of grief, expense, and delay the day that they need to claim. Its why the only insurance that I have in France is the minimum legal requirement to drive my car.

Were it to be a structural or health risk damp problem rather than purely cosmetic and were I to have to sell some day soon then the worthless piece of paper may actually have some value as something to hide behind, as much as the French adore expensive pieces of paper they do not in themselves put things right when there is a need, far from it usually.

Editted, Whats the betting that the 30 year guarantee that I was offered would not be transferable on the sale of the property?

In the old days the companies offering these long guarantees used to fold every few years as soon as the complaints came in, then they started selling the benefits of the insurance backed guarantees, now its the insurers that depose the bilan every few years [:-))]

[Salty Sam]

[quote user="Chancer"]

Do you say that based on results Salty Sam or the ease of use?[/quote]

Both! I've used the cream on a stone built property with excellent results, also on a brick built farmhouse where to be fair, much of the damp problem was due to wicking as the render was below soil level, and the damp had penetrated to the interior.

On both the above, injection was via the mortar as against the solid. Previous to these, I hired a setup similar by the sound of it, to yours in order to do an old railwayman's cottage. The brickwork was more like engineering brick and I experienced similar problems to those you describe, with a fair amount of wastage. I contacted the company who supplied the chemicals only to be advised the denser the brick, the longer it would take to perfuse the chemicals into the brick and displace any moisture present.

I got around the problem by drilling through the brick at angle, into the bedding mortar, followed by the fluid injection. After returning the kit to the hire shop, the final wall was completed by an array of cut-down plastic bottle funnels and pipe puttied into the holes, relying on gravity to allow the chemicals to be absorbed into the brickwork over a couple of days.

Then I discovered cream![;-)]

[Salty Sam]

Just a point on guarantees. As Chancer has indicated, there was a time when guarantees weren't worth the paper they were written on.

Yes, some guarantees are offered in the form of an insurance policy which is fine until the insurer vanishes or ceases to trade.

Many of the reputable dpc chemical manufacturers offer their own warranty against faulty material, but again these guarantees generally will only be valid if the work has been carried out by an approved, registered contractor.

[Chancer]

Well what I am doing cant be doing any harm, je m'amuse and it sure beats working for a living [;-)]

The wall did have some very rough tarmac against it, I have recently block paved the area, the front wall of the property has no damp problems, it too has a tarmac trottoir against it but good stuff paid for by the commune and it also has a fall that my old parking, pre block paving didnt. Critically it has a hydrofuge render band up to about 18" which i will be duplicating on the side and rear walls, that is probably all that is needed to stop the damp.

Also where the damp has risen over 90 years, probably caused by splashing it has brought up salts which themselves attract airborne moisture, perhaps it is them and not the rising damp itself that caused my crepi to fall off in these areas.

I have moved on to the next section of wall this morning, drilling into the mortar beds and getting a good seal each time, the pump has been running for hours at 150psi and I cannot even measure any fluid being used with my dipstick, perhaps they used a hydrofuge in the mortar, probably horse pi55 back then! I have several brick pillars and arches that I built to reduce the café window openings, I used sable à lapin the closest to Uk bricklaying sand mush to everyones chagrin, I will do a test injection in that to see if the mortar takes the fluid any better.

[Alan Zoff]

A surveyor friend told me that a lot of DPC "remedial work" is carried out quite unnecessarily. In his experience, the cause of the damp problem is more often high ground levels against the wall, or water seeping in from broken gutters and drains, damaged joints at roof level, etc. Such problems should always be looked for and tackled first but all too often some "expert" immediately recommends the expensive injection option.