Re: rendering

[DON]

Hi Cassis what a great reply,all sounds very plausible will give it a good try liked the mix you suggest,and the beer after naturally thanks again Don

[Cassis]

Good for you - do have a go.

Happy raking.

[zeb]

On the other hand you could use Parex which comes ready mixed in 25kg bags from the builders' merchants. It's available in several colours but, if your local outlet is anything like ours, they only stock the local colours (i.e. to compliment the local stone).

It costs 13 euros a sack and is mixed with water. Only do a small area at a time and brush back before it dries out completely. The beauty of Parex is that you can do a bit, and then come back to it days later and do a bit more, and the colour is the same. Also, you don't have to have piles of sand or a cement mixer, just a bucket and an electric whisk. May be a bit more expensive, but, hey, you only do it once, and this method is easier!

There are similar products, all around the same price, which are what French builders/facardiers use to spray on and brush off, to reveal (or not) the stones.

[Cassis]

Parex I only know as a manufacturer, not a product - they make a range of products.  I know they make a stucco type render for completely covering walls but I didn't know that it could be used for 'pierres apparentes' finishes too - thanks for the information.

If we're only talking about doing a bit of patching work then I can also recommend Terralit, which I have used once.  It is made by Weber.  But if you have a large area to do these ready mixed products work out a lot dearer - 13 to15 euros for 35kg compared to 20 euros for a tonne of sand bought in bulk from your local quarry.  Reckon on 11 to 12 euros for a 35kg bag of chaux or white cement.  As sand is the major constituent, mixing your own clearly works out a lot cheaper.  If you buy the sand from a local quarry and tell him what you want it for you will get the genuine local finish.

You have to mix the stuff regardless of whether you go for ready mix or the traditional mix-it-yourself solution.  Unless you've only a tiny amount to do you will need a cement mixer.  Saves your back and a lot of time and sweat.

[Boiling a frog]

Maybe the French artisans have got it wrong but our neighbours barn convertion has been repointed using Parex Monodecor GTP and also english neighbours have had the same done with a different company .Generally speaking  artisans put in on with a special mixer and compressor (not a cement mixer) however I have repointed the interior using the same stuff mixing it in a bucket with a whisk ( like you would mix plaster) Very easy to use no need to worry about  different sands cements and mixes you chose the colour buy as much as you need mix a batch put in on mix another batch etc etc it always comes out the same colour You can stop and come back weeks later etc.So what it is a bit more expensive than faffing about with sand cement getting right proportions  it is far easier ,and the big advantage you buy the colour you want not just boring or not quite right white

I do not recomend mixing in a cement mixer unless there happens to be several of you doing the job you cannot use a cement mixer load on your own without it going off

[Cassis]

The CAUE architect said that buildings frequently used to be re-mortared in the wrong (cement) mix by maçons, although it is less common now than it used to be.  CAUE advice is free, by the way. 

If you have a bucket and can count to 10 (in fact you don't even have to go that high) then you can get the quantities the same every time. 

I can vouch for the fact that you can apply a 50 litre load of sand and chaux well before it goes off - it does not set as quickly as a sand and cement mix.

[Boiling a frog]

But you just end up with whitish pointing

[Rasputin]

Just came across this forum, wish I'd found it 5 years ago.

Cassis is correct with what he says. It would be better with more lime and less cement (or even no cement at all is OK) - cement causes many problems, all of which you want to avoid (structural elements aside) - but there is no issue with it being too white. The traditional technique uses white lime (chaux) and it is simply the colour of the sand used that modifies the colour - so use the sand for your region and all should be well.

More recent mixes, using chemicals etc are fine but all they are trying to do is emulate this original/traditional look from sand and lime.

Cheers

 

 

[Cassis]

[quote user="Boiling a frog"]But you just end up with whitish pointing[/quote]

No, it is coloured by the sand.  The sand gives the mortar it's distinctive colour for the region.  Our mortar ended up with a very pale cream finish typical of houses around here and I'm told it will darken with age. 

Keep it covered with a plastic sheet in your wheelbarrow and if possible don't work in the sun as it dries everything out too quickly whatever mix or product you are using, as well as making it hard to keep the wall damp.

[Dave&Olive]

hi

           ok unless    you want to go down the  pure-ist  route , you are better of getting  "multi- bat " cement mix it 3.5 to 1 with local sand , it`s a pre-mix of cement and lime.

just make sure you buy in enough sand to finnish the job ,and use a bucket or tin to measure the the mix .

           dave

[Blitzen]

Great information source!  Has answered all the queries we could have before we make the mistakes we would have done, being complete novices at this kind of thing. 

[:D]

[legs_akimbo]

when you need to mix large quantities of render that are cement based then use a plastaciser or waterproofer in the mix, the less water content in the gauge the better and easier it is to work with. Fill the mixer with the compo to a stiffish consistancy and allow the plastaciser to do its stuff, as the mixer drum turns it will cream the mix to a nice consistancy after about five minutes. You will know you have it right when in the barrow the water does not after a while rise to the top and the bottom of the barrow is hard stiff compo....it should stay consistant at all times. If you have no plastaciser or waterproofer then a squirt of washing up liquid works just as well.

[steve]

thats not pointing a wall, looks more like someone has thrown muck all over it and brushed it off.

there is hardly any stone left showing.

this has got to be a windup, surely there can not be anybody who would  want that done to their house

[Dick Smith]

Have you read Phil's post, Steve? The bit about brushing the excess off again?

[Chris Head]

I take it you're an expert Steve? I suspect you'll be cringing in the morning if/when you dare re-read what you wrote. Cassis is a mate to many of us and you've dissed him Steve, probably in a p1ssed state but who cares....you're probably one of the army of DIY'ers here who have become renovation experts overnight.

I don't think I've read many more informative posts on LF than Cassis' post, it may or may not contain faults, I personally don't care, Cass helped alot more folk than you ever will do Steve. 

[Cassis]

[quote user="steve"]

thats not pointing a wall, looks more like someone has thrown muck all over it and brushed it off.

there is hardly any stone left showing.

this has got to be a windup, surely there can not be anybody who would  want that done to their house

[/quote]

Thank you for your kind and well-informed comments, Steve.  I'm sure everyone will find them very helpful.  Do feel free to carry on in the same vein.  I look forward to replying to your future posts.

PS If you pay a little more attention you will see that the building in question is a former cowshed - not exactly dressed stonework.

[cooperlola]

Looks better than I could have done Cassis!  Have you finished with your light-weight pick thingey? - sounds like a good piece of kit.

More toy throwing.  Loverly.[:D]

[Cassis]

Indeed, Coops.  Keeping things lively, eh? [:D]

[cooperlola]

True.  Btw, I had always wondered if I would recognise you if I passed you in the supermarket in Alencon.  Now I've seen the pic of you rendering your cow byre, I realise your avatar is such a good likeness.  No probs.

[sharkhunter]

Hi Cassis, the reason i think they say start from the top is basically one thing. When you apply water to keep the walls wet to aid adhesion if you start from the bottom there is a chance that the water will wash out the mix below, from the top the water will continually soak the stone work below, appliance of science  ( the space martians quote~~ see mash get smash )

Also, if you start at the top, this is the good bit, if you're crap at it, by the time you get to the bottom you're getting better and folks can't see the messy top bit too clearly... da naah

enjoy your sunday

[Chris Head]

Like the logic Hugh! I need one of those picks to deal with my creme brulee.

[WJT]

Cassis, if you ever decide to come our way to the Dordogne, I could keep you very busy with your pick. In fact, it could even take a few years. [:)]  I also think it would be a real novelty for the neighbours to have first hand experience of an English sausage.

By the way, I think it looks lovely, well done.

[sharkhunter]

chris, are you saying that the creme brulee you get at home needs more than a spoon, careful or your wife may use the pick on you

[Cassis]

Steve may think my results aren't very good but the advice regarding the use of chaux mortars, passed on from the CAUE, remains valid.

[steve]

chris, drunk and regretting my post. no. i keep looking at the picture and it is the same. one of many diy,ers i dont think so. you say i must be an expert, well 27 years experience in the construction industry says i know what i am talking about.

are you an expert with a chainsaw ? probably not, but i would think you are as good as you hope to be and your advice on that subject is taken with respect.

i reply to posts to pass on knowledge for the benefit of others, and i look to do the same.

i encourage any diy,ers to have a go and if the job turns out reasonable then they have cracked it,

cassis, you have attempted something. in your eyes suceeded and you do not deserve to be put down by me for that i do appologise, i should have kept my comments to myself

i have set myself high standards for any work that i take on. if i could not turn out first class work then i wouldnt bother doing it in the first place.

i joined this forum to gain sound advice and i have done so, but my opinion remains the same, as in if you cant soundly advise someone. perhaps its best kept to yourself.

cassis, i do not mean to offend you, far from it , i am on here to learn about stuff i do not know. i just think that your advice and proof of how to repoint a stone building is not very good. if you are happy with it and you obviously are then you deserve a pat on the back.

i am not out to p**s anybody off, 

i have recieved negative replies to previous posts but still managed to stay in my pram.