Chemical Injection DPC

Verb

Hi

I have just had a chemical injection DPC installed into the mortar a few weeks ago.

I have had 2 walls injected:
1 - The outside front from my front door under the bay window to my neighbours house
2 - The inside of the garage on the original external house wall (the back of my garage is a kitchen extension, built 20 plus years ago)

When I'm looking at the line the holes have been drilled for the chemical injection.
1 - There 1 course up from my front door threshold (and at the top of the air brick)
2 - Inside the garage, the 1 wall that was injected is 1 course above the DPC from the wall that wasn't done

As far as I can make out the injected DPC is now inline with half way up my skirts inside.

My house is a solid floor construction, is this chemical injection correct or am I right in assuming its 1 course too high and damp will transmit into the skirts and possibly into the plaster behind the skirts (the plaster does not go to the floor, there is a 50mm gap) 

neilmcl

Damp proof injection is one of the biggest cons in the building industry.

stuart45

If your house had an existing DPC, why was it injected?

neilmcl

stuart45 said:

If your house had an existing DPC, why was it injected?

I bet he had a "survey" that insisted he get it done 😉

Total rip-off.

Verb

stuart45 said:

If your house had an existing DPC, why was it injected?

It never had an exsisting DPC, the house is 90 years old with an extended kitchen and garage built 20 plus years ago and another extension built 2 years ago. The kitchen extension makes up the back wall of the garage and this is fine, hence this wall was not treated. 
The original 2 sides of the house, front (bay window) and original side of the house that is now in the garage has damp. This is why only these 2 where done.

neilmcl

Verb said:

stuart45 said:

If your house had an existing DPC, why was it injected?

It never had an exsisting DPC, the house is 90 years old with an extended kitchen and garage built 20 plus years ago and another extension built 2 years ago. The kitchen extension makes up the back wall of the garage and this is fine, hence this wall was not treated. 
The original 2 sides of the house, front (bay window) and original side of the house that is now in the garage has damp. This is why only these 2 where done.

The big question being what is the source of the damp.

Mickey666

neilmcl said:

Damp proof injection is one of the biggest cons in the building industry.

Sadly true.  Did the OP not research this ‘technique’ before agreeing to it?  Loads of info online, here’s a starter though there are many more authoritative sources; https://www.homebuilding.co.uk/advice/can-injected-damp-treatments-damage-your-home

 Damp and woodworm - two words that open the wallets of property owners everywhere

Doozergirl

You're right to be asking questions but it would have been better to ask them before, sadly. 

The whole thing is a con.  The house stood for 90 years, apparently with no DPC, so why does it now one now?   They don't even have the (pointless) argument of the last one having 'failed'.  

Where was the water coming from?  Did they tell you that? 

Verb

I'm fine with getting the DPC done and I did my research as the ground in my surround area is very damp and it has to do with an old brook that was rerouted when roads where built up 90 odd years ago. The ground still likes to hold the water.
Thanks for all the wonderful comments about, Its a con and total rip off and that is really what I want to be reading from all the construction experts.
My only question is, is my chemical injection 1 course too high. As I want to see what constructive comments there are that may or may not agree with what is in my head.

Grenage

Verb said:

My only question is, is my chemical injection 1 course too high. As I want to see what constructive comments there are that may or may not agree with what is in my head.

As the injection will have little to no real effect, it's neither here nor there as to the level.

Doozergirl

You can have varying levels of DPC as long as it's consistent, but an injection does ziltch anyway so it doesn't matter where it goes.  

 If you build a new house,  the DPM goes under the building and laps over for the rest to be built on top, making the house actually damp proof.   Drilling a few holes and injecting them at random intervals doesn't form a protective barrier.   It just doesn't.  Water is in tiny molecules, it's going to find its way though if the ground is soaking.  

The injections do nothing.  It's the waterproof render they put on the walls that traps it in the wall and stops you from seeing it from inside, but it's still there if you haven't stopped the source.    Give it a few years and the damp will start to show above the 1 metre line of the render.  

I've been doing this way too long and seen walls with even several injected DPCs still doing nothing.  In each case, I've found the source, stopped it, let the wall dry and, if I'm still worried about moisture and the house not being able to breathe, had it plastered in lime, which would actually let the damp out.   

If you have nice new waterproof render, you've just bought yourself a sticking plaster and some time. 

I'd still be looking for a genuine cause/solution.  If the problem had been ongoing for 90 years, the house would have suffered for all of that time.  Something's changed.    Some solutions are cheaper than others, but there's always a lasting solution.  

I can't dress it up prettily for you. Sorry.