[Closed] Quick DIY question - advice needed 🙂

Just doing my garage with this stuff - using bostik / Cementone Aquaprufe.

[url= http://www.bostik.co.uk/diy/product/cementone/Flexible-Damp-Proofer-and-Waterproofer/156 ]http://www.bostik.co.uk/diy/product/cementone/Flexible-Damp-Proofer-and-Waterproofer/156[/url]

As recommended by my builder neighbour. But will also be fitting a vapour barrier.

Would think about treating the outside brick work with a breathable waterproofing product too.

Cheers Jeff.

Where did you buy it from?

How have you found applying it?

We were advised by friends to seal the inside of the brick work with a bitumen paint or brick sealer.

Ive always preferred brick/block/stone/mortar above the DPC to breathe personally. If there's risk of damp (cant see how? is there a DPC?) then you could stand the stud off the brick on rubber pads and leave an air gap between the insulation and the wall? But Im just a DIYer not a builder, so wrightyson or one of the others may be in in a minute with better knowledge.

Nice + easy to work with, not too smelly, goes on easily, but is a bit watery.

I've got earth above the DPC (don't ask) on one wall, so we needed this. See my edited post about treating the outside wall too.

My garage looks a bit like a goth's bedroom at the moment 😉

If there is damp and you seal it up, you'll just force the moisture to move somewhere else and cause a problem there. If you have a DPC above ground level, then there should be no need to seal above that. If you don't have a DPC then you have to provide a path for moisture to escape ie you can't just seal inside and out and expect the moisture to just vanish....

Only doing 600mm up the walls on the garage. Will then batten and keep an air gap between wall and the lining.

Thank you for the responses.

As it stands I don't think that there is a DPC as where there has been skirting board tacked to the hardboard the tacks have rusted over time.

Added to this the ground on the other side of the wall is slightly higher than the floor level inside the conservatory.

Sadly nothing can be done about the land level as the ground does not belong to us.

footflaps - Member

If you don't have a DPC then you have to provide a path for moisture to escape ie you can't just seal inside and out and expect the moisture to just vanish....

Understood.

What are my options? Just seal the lower bricks as a barrier to damp from the other side?

The exterior of the wall has a sandtex exterior paint applier to the brick.

Stoner - Member

then you could stand the stud off the brick on rubber pads and leave an air gap between the insulation and the wall?

The celotex and plasterboard are about the same depth as the already existing void 😕

My understanding is that the celotex could be stuck to the bricks then the plasterboard to the celotex but that would leave no air gap at all 😕

Get thinner insulation. Xtratherm comes in a number of thicknesses.

But first as footflaps says, I'd think about moisture route.

You might consider an injectable DPC above the outside level and then a hydrophobic tanking treatment and render on the inside of the dwarf wall. But that needs taking into the slab or you just push moisture out on to the slab. Have had this done in a lower ground room before and it works very well.

All a bit tricky really without having a closer look. And probably getting a pro in.

Stoner - Member

Get thinner insulation. Xtratherm comes in a number of thicknesses.

But first as footflaps says, I'd think about moisture route.

You might consider an injectable DPC above the outside level and then a hydrophobic tanking treatment and render on the inside of the dwarf wall. But that needs taking into the slab or you just push moisture out on to the slab. Have had this done in a lower ground room before and it works very well.

All a bit tricky really without having a closer look. And probably getting a pro in.

Will have a look for some thinner insulation board.

Not really looking to spend a huge amount as this is additional work I am doing inline with a new kitchen & layout change. Hmmm.

If moisture is in the lower bricks of the dwarf wall - which I suspect - could I not just add a sealer to the affected courses similar to Jeff's scenario above?

If the moisture heads up the bricks then there would be external air circulation getting to them.

Or am I missing something major here?

A liquid applied damproofing like RIW on the inside will seal the surface and prevent water getting in. Does it have a horizontal DPC anyway? If it were mine I would put some 50x25/38mm timber battens with a DPC between it and the brick and then and then an insulated plasterboard. I seal a single skin brick wall from the front and only down to DPC level.

We used Newlath 2000 to successfully remove the cause of damp in a kitchen which we renovated. It was single skin brick too. You attach the newlath to the wall with plugs and silicone, it provides an impermeable membrane with air circulation space behind it.
You can dot and dab directly to it with plasterboard or insulation backed board.

Taff - Member

Does it have a horizontal DPC anyway?

No DPC that I am aware of. - If one is present, which I doubt, its at the wrong level.

Being a bit thick this morning..... what do you mean:

Taff - Member

If it were mine I would put some 50x25/38mm timber battens with a DPC between it and the brick and then and then an insulated plasterboard. I seal a single skin brick wall from the front and only down to DPC level.

Taff means:
use bits of DPC between the battens and the wall as a moisture proof barrier (I referred to rubber pads, same thing).

Then rather than cavity fill with insulation, you can use plasterboard that has polystyrene layer attached directly to the battens, which retain the air gap to the wall.

Ah its makes more sense now 😳

Will take down the boards tomorrow and maybe post up some pics if needed.

Cheers all 8)

Even if the ground (that is too high) is not yours you still (I believe) have the right to access it to fix issues affecting your property (I'm sure someone will correct me if I am wrong!). Talk to the owners and if they agree for you to access it, then I would look to put in a vertical DPC and inject a DPC from the inside. We have a concrete path next to our house above the DPC but it has a vertical DPC also and this seems to work well. We do have sunken airbricks as well for airflow under the suspended wooden floor.
A builder did suggest a french drain to shift the water away properly but as long as I keep the airbricks clear we don't get any issues.
Definately keep the batterns off the wall with rubber gaskets and allow airflow as this will keep too much damp at bay anyway!!

Good luck!