Limewash experts - help please

[Me!]

OK, today I have just had my first attempt at making and using limewash, and things have not gone well!

Before starting, I did lots of searching through this forum and got the usual two viewpoints on "lime putty is much better than dry hydrate" and "dry hydrate is fine". So, as I have successfully used dry hydrate on several occasions to make mortar, I decided to have a go with that.

The first problem I had was (following the advice given many times on this forum) that after putting on rubber gloves, a dust mask and safety glasses, I found that as soon as I exhaled my first breath it was diverted by the mask straight in to the safety glasses which instantly streamed up! I tried adjusting the positions several times, but the same thing happened every time. So, honest answers please, I promise I'm not a health and safety inspector, does anybody really wear a mask and safety glasses when mixing hydrate with water? If so presumably it can't be the disposable dust masks that I tried, so what kind do you use?

Anyway, risking life, limb and lungs, I removed the mask and started to mix hydrate into the water until I got a white liquid that looked like milk (as described in posts on this forum). I'm using this indoors to paint on a lime plastered surface so I decided not to add any linseed oil or anything else as this seemed to be the consensus of opinion.

I then left it to rest for a few hours and stirred again before use. I sprayed the plaster surface with water, and used a brush with stiffer bristles than I would normally choose for modern emulsion. Well, trying to paint a ceiling with something the consistency of milk is quite a challenge! The limewash is not viscous enough to stay in the bristles of the brush when held upside down and a large amount of it was soon running down the handle of the brush and my arm! So, basically painting something this consistency on a ceiling doesn't seem to be realistically viable unless I've missed something. Any suggestions please as to where I am going wrong?

I have also tried a small patch with a much thicker mix of limewash, more like double cream than milk and this did seem to apply much better. But various posts suggest that this will either not adhere correctly or will crack as it dries. Again, any knowledgeable opinions would be very welcome please?

One positive note to end on though is that Osmo can add limewash to the list of things their oil can withstand. The many drips of limewash have wiped off the floor without leaving a single mark.

 

[yamin]

Poor you! I'd be interested in replies on this as I plan to limewash my newly plaster patched wall, that I did myself in lime plaster Anyway, re your point on mixing, I mixed the plaster from dry hydrate, in the garden shed, using an old plastic cup and my cardie material over my mouth and nose! Come to think of it I do have a cold, but think its just that, a cold! Does fly around a bit though.
Re the consistency, I read two things elsewhere, one is to make it the consisitency of double cream as you tried, and two is to leave it for a few days rather than hours before you use it. I guess only way to find if this works is to do a patch as you have and see whether adherence or cracking is a problem. My feeling on these things is that lime plastering and traditional work practices like this were always going to be subject to varied opinions and varied results, and though you listen to basic advice, thereafter your work is going to depend on the your particular walls and technique, know what I mean?
Just my twopenneth! General advice? Suck it and see!

 

[MdB]

I mix outside and use a mask. If I put goggles on, they steam up quickly as you found though I do wear both goggles and mask for the worst jobs. I just have to clean out the goggles frequently.

 

[biffvernon]

I've never used a mask for mixing lime - but I've missed my chance to die young.

The drippy down the arm problem is a problem. Some brushes work better than others but don't overload the brush.

 

[Feltwell]

I tend to use safety specs rather than goggles - not as much protection but a lot better than none, and they don't steam up as easily. The mask you use makes a big difference - get a decent mask (3M or similar) and they are valved to let your breath out more easily, so the "filter" bit only works as you breathe in, if you get my drift. They also tend to have an aluminium strip over the nose on the better masks, which you pinch to match the shape of your hooter.

Also - go to any motorbike shop and you will find various anti-mist potions, used on the inside of visors and goggles. I always use something when off-road riding (which is seriously hard work at times) as otherwise the goggles mist up instantly. Makes your vision much better, but still not perfect.

 

[Feltwell]

The drippy down the arm problem is a problem. Some brushes work better than others but don't overload the brush.

Wandering off topic slightly from limewash to linseed paint, the "spoon" brushes that Holkam's sell for their linseed paint are dreadful for that. Painting anything that requires the brush to be the wrong way up even briefly isn't a good idea. Their brushes are OK but personally now I'd just use an ordinary brush and dip it in the tin a little more often.

 

[Schoolmarm]

I thought we were supposed to mix it to the consistency of single cream.

 

[Flyfisher]

Has anyone tried using a roller? I'm wondering if it would hold the limewash better than an upturned brush. Or those pumped-up container thingies that deliver paint through a hose to a roller on the end of a broomstick - specifically designed for ceilings I gather. Not that I've tried either.

 

[biffvernon]

Painting anything that requires the brush to be the wrong way up even briefly isn't a good idea. Their brushes are OK but personally now I'd just use an ordinary brush and dip it in the tin a little more often.

Yes, I find it best to take the ceiling off and lay it on the floor for painting. Interesting what you say about the Holkham brushes. I''ve allways been too mean to fork out for one. Good to know I'm not missing out.

 

[fjpdesigns]

Never done a ceiling but do remember years ago seeing a sort of funnel thing that you push over the painbrush handle to catch the drips. Maybe you could cobble one together from something like a cut off milk container? ( Using lots of sticky backed tape of course)
I use ordinary brushes to limewash. They do hold it better. And I would suggest you use a brush with light coloured bristles, then if you inadvertantly leave a bristle stuck to the ceiling, which inevitably happens, it won't stand out like a sore thumb.
Only apply one coat per day, or even every other day. I start with a couple of coats the consistency of milk. Before the third coat pour off a bit of the water that has settled out overnight so it is the consistency of single cream. I wouldn't try it any thicker. Make sure you sieve the limewash before you use it, and as you have done already, spray with water before you paint - but don't apply the limewash if there is still water visible on the surface.
As an aside, why is it sticky backed tape and not sticky fronted tape?

 

[ian]

The dust problem is one reason to use putty. You could try adding the water to the hydrate which would reduce the dust cloud considerably while standing out doors, up wind on a breezy day. I find the best consistency is 2 part water to one part putty by volume- which would probably equal 3 parts water to 1 part hydrate as the putty is already wet. Natural bristle brushes seem to work well, and as thick as possible front to back. I have found some 4 inch wide that are about 3/4 inch deep - I think by Harris. I have not tried the short haired fence treatment type brush, but feel they may work well for the first few coats till the surface smooths up.

 

[Jon Maine]

Has anyone used and old food processor to batch their limewash yet?

Would it be to aggressive?

May make a more consistent mix more quickly and once you have put the lid on no more dust.

 

[yamin]

Been there done that - my husband was kind enough to take a photo

http://photos-d.ak.fbcdn.net/photos-ak-snc1/v373/58/62/1293183786/n1293183786_142091_4960.jpg

 

[biffvernon]

That's the limewash in the old milk bottle is it? We've got one that we stick flowers in.

 

[yamin]

You see, theres no need to let standards of appearance slip, all this talk of goggles and masks. You just need a nice pinny and some hair rollers and you're all set. And a nice bit of lipstick for when hubby gets home......

 

[skier-hughes]

Interesting what you say about the Holkham brushes. I''ve allways been too mean to fork out for one. Good to know I'm not missing out.

Never getting on well with any make of brush I've bought I invested in a small and large one from Holkham and I think they are wonderful.
I haven't lost a bristle yet, and the ease of painting I find much better.
I've been using the larger one to linseed oil the beams, some of which is upside down and so long as the brush isn't overloaded I haven't had any running down my brush.hand/arm.
I'll be buying more, if these wear out.

Could you use a sprayer to apply the limewash? Something like a garden sprayer for weedkiller?
Like this
http://www.garden4less.co.uk/proddetail.asp?prod=4465

Graham

 

[worms]

Could you use a sprayer to apply the limewash? Something like a garden sprayer for weedkiller?

Don't do it! I tried this last year, the sprayer blocked up after about 30 seconds of spray and it then took most of the afternoon to clean out the inner workings of the sprayer! I'm sure there are paint sprayers that might cope with this, but my standard garden one didn't! And the sprayer hasn't been the same since - yes all the parts are replaceable, but it isn't really happy being taken to bits and put back together again.

I've tried a paint roller, which wasn't great, a standard floor mop seems much better for walls and a cloth for the window recesses, but I am talking about the exterior of the house, where the drips and splashes are not so critical!

 

[Gervase]

Limewash has to be brushed on vigourously, I'm afraid, or it won't stick. I use cheapo soft coco hand brushes (this type) for limewashing if mess isn't a problem - and for big, flat exterior walls, a big coco floor broom.
For neater work and for ceilings, use a four-inch natural bristle stonework brush. Most builders' merchants sell them.
I wouldn't worry about a mask, but some form of eye protection is a must. I wear glasses, but always keep an eyebath and a bottle of eyewash in easy reach. Limewashing splashes, and if you get some in your eye it will hurt like heck and could cause lasting damage. Don't risk it.
To be honest, you get a better limewash from proper putty, as that's made directly by slaking the lime and has never had a chance to react with the air, but if cost is an issue then by all means have a go at making your own putty.
Use the freshest hydrated lime you can get - stuff that's been kicking around in bags for a couple of months is not much good; you need the first bags off the new pallet that's just arrived at the builders' merchant. Steep that in water for a week or so, and use that putty to make your limewash. Use a paddle mixer on an electric drill to whisk it up thoroughly, and keep stirring while you're slapping the stuff on to stop the lime from settling.

 

[Me!]

Thank you all for your advice, both the sensible and the humorous were gratefully received!

So, for day two and the second attempt, .......
I checked, and the small test patch I had tried with a double cream consistency seemed to be well stuck to the ceiling, not cracked and nicely opaque, but it had a very uneven surface presumably due to deep brush marks in such a viscous mix. So, I made up the next batch of limewash (outdoors, upwind, with goggles and no mask) to somewhere between milk and single cream. I selected a new, natural bristle, ordinary paintbrush and sprayed the ceiling with water and had another go. Well, what a difference! Very few drips and it went on easily. As Gervase said, it is a vigorous brushing action that is needed, but I found it much easier with an ordinary brush rather than the stiffer version I tried earlier. I even stopped wearing my rubber gloves as there was so little mess!
This evening, I have just put a second coat on using the same method, and it is really starting to look good. I'll leave it until the weekend now, and then probably do a third coat on Saturday, and hopefully that will be sufficient.

Sorry, but I do have two more questions though for you lime experts out there please. Firstly, is there any way to tell if hydrate is too old to use? Secondly, can I assume that once I have used the limewash made from hydrate of uncertain age, that as long as the limewash turns bright white after 24 hours that carbonation has occurred and that it must have been OK?

Thank you again.

 

[worms]

I, too, am looking forward to the answer to this one! Last summer (against all common sense) I used a bag of lime that had been opened the previous autumn and it seems to have been ok as mortar for pointing. I'm not sure that your second assumption is correct (think chalk on a blackboard!).

However, I reckon the correct advice is probably that at £7 or so per bag it is not really worth the risk and in my case the residue from an open bag can always be used to reduce the acidity in the borders below the Leylandii!