Bitumen Emulsion & Whitewash

[SpinningNickel]

Please bear with me if there are lots of silly questions here -- I'm a novice DIYer anyway and this is totally new territory for me! I struggled with which forum to drop this into, too, so hopefully this is ok...

I have a late 19th-century back-to-back terraced house, which has a moderately damp cellar. I just want to be able to use it for storage, but as there is a possibility of having a full professional kitchen conversion done in a few years, I don't really want to throw loads of money at it in the meantime.

The plan has been to take some scrapers and/or wire brushes to it firstly, to get rid of the layers of old plaster and paint and washing everything down. From there, I'm toying with the idea of 2-3 coats of rubberised bitumen emulsion on the walls and floor to provide some rudimentary damp proofing so that I can store things on racking or pallets without it all being instantly destroyed.

My question is really about finishing (although if anyone has any insight into whether or not my basic plan is useless, that is welcome). How do you finish over this stuff? The information I can find is to blind with sand and apply render/plaster/screed over top. Do I have to do this? Can I just paint it or something? As it's only a cellar and I am a novice, I don't want to push my luck with rendering or screed and am inclined to use some kind of slaked lime whitewash -- cheap and bright, and technically more plaster than paint anyway. Will this work? Will it work only for the walls, or for the floors too? Will I still need to blind (I'm guessing this rubberised emulsion is very smooth and any finish will slide off it)? And perhaps the stupidest question of all, how does blinding actually work? Do you literally throw sharp sand at wet emulsion?!

Thank you!

-Nic

 

[dcdec]

Your on quite tricky ground really as your looking toward a paint covering to solve a damp issue.
I'd avoid any bitumen coating as they're tricky to deal with when re-dec comes.

The only thing that springs to mind is a zinsser product called watertite, i think you can paint over it but check ( i havn't read the blurb), i came across it a couple of years ago while speccing a job but didn't need it in the end.
A de-humidifier might help as well.

 

[dcdec]

Oh, forgot, here's the link

http://www.zinsseruk.com/shop/Product.aspx?cId=128&pgId=347

 

[oldgreymouse]

Nic, it does sound as if you are heading into a whole big job.

As dcdec has said, avoid the bitumen coatings, it is not the sort of thing you want on the walls if you have another plan for a kitchen later on.

I have done some work on old vaulted cellars and basements but only to make them a bit more usable.
Couple of questions, is the cellar damp on all four walls and floor? To test the floor for damp, place a piece of cardboard on the floor then check the following day for a darker patch under the cardboard, if so, the damp is natural and you would be better sticking to just using a coloured limewash for now and leave the actual 'tanking' out for when you do the kitchen.

Also, do you get more signs of damp to the cellar front wall of the house, is it close to a road and getting water run off from that?
Most houses with cellars have no damp proof course because they are so low underground, but the walls were supposed to breathe and were never painted, only limewashed to make them reflect the light.

http://www.traditionallime.co.uk/

To make it usable, do the limewash in white or a colour, or just brush it down and leave without any coating, then depending on how long you want to store stuff on the floor, look out for the plastic mats with the holes in, saw some at a local auction last week but not sure where they come from. They lock together and would allow the floor to breathe. I have used pallets before to keep cardboard wine boxes stored off the floor, it worked but you need to keep checking them.

 

[SpinningNickel]

Ok, cheers. I gather the stuff is basically tar but it didn't really occur to me that is might not be easy to just cover over down the line.

I'll put a bit of cardboard down today and check that tomorrow as suggested to see how that comes up and will report back. The damp is definitely worse at the front, but it's hard to say exactly why. Because it's a back-to-back terrace, there's obviously only that wall and part of a side one (which borders the alley between the houses) which are external, but I think the front corner does get some run-off from the road and neighbour's drainage.

The front also has an actual hole in the wall, which doesn't help... There's an old window which got broken and which we decided just to board and perspex for the time being as that looks fine and is secure, but for some insane reason, previous owners routed the drainage from the kitchen right down the centre of the cellar, through a hole cut into the windows, and into a grate outside to the front. Why this was not just done through the external wall directly behind the sink/washer and drained into the alley between houses like all our neighbours' is baffling to say the least, and it's another job on the list! Anyway, I also need to seal round that drainage pipe and I imagine that will help considerably.

The Zinsser product apparently dries bright white anyway, which might negate the need for a limewash over top anyway... Does anyone have any experience with that product?

Oldgreymouse, do you mean JUST limewash it? I'd probably avoid keeping stuff directly on the floor in favour of outdoor-suitable metal racking anyway, for the sake of organisation and just to be on the safe side, so I'm guessing I can theoretically get away with this if the damp isn't too bad and I get that opening watertight..?

 

[oldgreymouse]

Sorry for that SpinningNickel, I may not have made myself clear in the reply.

Basically, I had meant that you would limewash the walls, not the floor.

On the floor, I had suggested using a rubber matting that had holes in it. I had seen some for sale at a local Auction house. We used to buy some 3ft x3ft squares of similar stuff for about £25. A little bit pricey for what you need but as you say you might use shelving, I guess you would not need it.