Internal damp - Restoration of Quarry Tiles

[jonewer]

I have a problem with damp on an internal wall and I'm baffled about where it coming from.

The wall is totally internal - doesn't have contact with an outside wall. There is a radiator against it on one side, but the pipework there is all dry.

It seems the floors are solid and probably originally quarry tiled (its as 1880's build), at least I know the floor one side is quarry tiled, dont know about the other as its covered in laminate.

Even more confusing is the fact that there are air bricks, which are placed such that they would lead to underneath the solid floor. What could the reason be for these airbricks? If they were blocked with a century and a bit of dust and cobwebs, could this cause internal damp?

Thanks.

 

[foxhole]

Vents under the floor allow any timber floors to be ventilated.
Any pics?

 

[jonewer]

OK, so after having a complete waste of time and money damp surveyor in, a bit of googling reveals that quary tiles should never just be carpeted or otherwise covered over with plastic or non-breathable materials.

The floors were actually wet to the touch below the underlays because they couldnt breathe and the damp in the wall was probably due to this moisture wicking up the plaster on the walls (no gap in the plaster behind the skirting boards either!)

So, now the question is - how do I restore these quarry tiles? A lot of them are utterly filthy. Some may have to be replaced and some still have nails stuck in them from where the barbarians nailed the carpet grippers into the antique original floors!

I really dont want to do any more damage so any advice much appreciated.

Thanks!

 

[ree]

The air bricks might have been venting the original suspended floor, that has since been poured as a solid floor.

Does your concrete floor have a membrane under it? By removing a convenient or short length of skirting you can usually see the membrane lapping up behind the skirting. Perhaps thats what you've already done?

The wall plaster should be cut 50mm short of any floor contact on all walls above solid floors.

It sounds as tho your solid floor was poured without a membrane and damp is weeping thro the floor.
Perhaps the solid floor has bridged the DPC in the internal wall?

If you post pics of the floor wall junction (without the skirting) maybe we can help you further?

 

[ntb]

To remove the nails use a thin piece of wood to protect the surface as you lever them out with a claw hammer or pincers.

Start with some elbow grease and give them a good scrub with a stiff brush and soapy water. That should get them looking pretty good but if it doesn't, post a pic.

 

[jonewer]

Yes, the solid floors were obviously laid in place of the original suspended wood floors. However, this must have been done quite a while ago as they are obviously very old quarry tiles.

As such, there is no damp proofing under the tiles which is why the non-breathable modern underlays were causing such problems. I don't think the internal walls have any DPC either.

To clarify my nail problem – I used a jemmy to get the nails out but some of them were corroded, meaning the nail head simply snapped off. I now have at several places about 5mm of rusty sharp metal bits sticking around the edge of the floor. Obviously not ideal. Any suggestions? Maybe hammer them all the way in?

Will post some photos when I get home.

 

[ntb]

I'd be inclined to just file them down. You risk breaking the tiles if you try and hammer them in.

 

[jonewer]

OK, so here's some photos...



This shows the damp patch on the wall and the radiator pipes I thought were causing it. There obviously was a leak there but it's equally obviously old and the pipes are dry.



This is where the hall way joins the dining room. Note the condition of the tiles. They have laid modern tiles over the old tiles which is causing damp in the hallway too. Nice. Will have to dig those out too!



This is one area where the tiles will have to be relaid.



I removed the skirting boards from this area. Note the plaster joins with the tiled floor.



Tiles in the dining room on the other side of the wall with the damp. Some in pretty poor nick.



Damaged tile. Note the pattern left by the underlay.

 

[ree]

I think that you have damp coming up thro the concrete - i would also suspect that rising damp is affecting the walls here and there. The moisture came from somewhere, and as there are no signs of condensation in the pics i'd suggest that it came up from the soil.

The hearth areas might be particularly affected because the tile could be laid on a very thin skin of concrete over the hearth fill soil.

Often people clean up the tile and carry on - the old tiles give character to the floors, and the damp is no big deal in warm well ventilated rooms.

If you decided to lift all the tile then you might consider replacing the slab. Lifting old quarry tiles can sometimes be difficult - the old "adhesive" was a S&C slurry, often set on a wet screed. The grout is also S&C.

 

[jonewer]

I think that you have damp coming up thro the concrete - i would also suspect that rising damp is affecting the walls here and there. The moisture came from somewhere, and as there are no signs of condensation in the pics i'd suggest that it came up from the soil.

Yes - for the record - I'm 99% sure that what has happened is that moisture has been rising through the tiled floors.

This would not be a problem but the floors were covered in laminate on one side and carpet on the other. The waterproof underlays meant the moisture had nowhere to go, hence the floors were actually wet to the touch.

Obviously, this wetness has to go somewhere, so it rises up the walls, causing rising damp.

Once the laminate and carpet were stripped and the tiles allowed to breathe, the floors dried out in a matter of hours.

The hearth areas might be particularly affected because the tile could be laid on a very thin skin of concrete over the hearth fill soil.

Sorry, the photo is misleading here. The hearth area appears to be badly affected by salt deposits but that's just because the photo is too small. Its actually the case that they dug the tiles out where the hearth is laid and the light coloured area around the hearth is where they used cement to lay the tiles.

Often people clean up the tile and carry on - the old tiles give character to the floors, and the damp is no big deal in warm well ventilated rooms.

If you decided to lift all the tile then you might consider replacing the slab. Lifting old quarry tiles can sometimes be difficult - the old "adhesive" was a S&C slurry, often set on a wet screed. The grout is also S&C.

Yeah, like I said, they dried out in a matter of hours once allowed to breathe so if we can restore them to a reasonable appearance we will likely keep them and throw a few rugs down.

What is S&C by the way?

I have ordered a damp meter and will update the thread with reading so that if people with a similar problem find this thread, they will have access to the info.

If anyone has tips on how to clean quarry tiles, I'd be really grateful!

Thanks all.

 

[geraldthehamster]

If anyone has tips on how to clean quarry tiles, I'd be really grateful!

Thanks all.

I cleaned up some quarry tiles quite effectively with brick acid (aka patio cleaner), but I was working outside. Inside you're better off using a proprietary cleaner. These links might be helpful:

http://quarry.tilecleaning.co.uk/

https://www.youtube.com/watch?v=EuWkOWpOSlY

Cheers
Richard