polperro ripple

[davidtrebor]

hi, i could do with a bit of advice. ive been slowly restoring a house for my client, im a joiner by trade and have been restoring the windows and doors and various other bits of woodwork, however ive been asked to repaint the outside of the house, which is finished on the top half in a style called polperro ripple, its a cement render, some of which is good but some is shot and crumbling away. the house dates to the 1700's its 2 cornish cottages, that were renovated in the early '70s, i originally thought that it had been finished in lime render but having done some tests and taken advice, now know that it isnt, and is cement on cob, not ideal i know but i could do with some advice on firstly the right mix to use to repair the shot top coat and secondly how to achieve the polperro ripple style. i realise that ideally it would be better to replace completely the shot sections but thats not possible due to the nature and budget of the job. the building is grade 2 listed so ive got to get it right, ive some basic experience in rendering but any help would be gratefully recieved. ive removed all the loose and crumbly stuff, it looks to be a section whereby the original mix wasnt right, the wall is north facing so doesnt get any sun.
id appreciate tips on the right mix to use, i thought 1 lime 1 cement and 4 sand.

help! cheers dave

 

[lucius]

Google Mike Wye Lime plastering hese down your way so should have some local knowledge.

 

[Dansouthcoast84]

A building that age should be sand lime. A course coat then lime finish.listed buildings are strict on materials

 

[Render Systems]

yes definatley need lime mortar here, the building would have been originally built using this and repaired badly ovet the course of time hence its knsckered now, and if anyone tells you different they havent got a clue as cement mortar wasnt even invented until the early 20th century, use NHL 3.5 Lime mortar, course stuff to dub out , then course stuff to level then fine stuff for the top coat, post a picture of existing and i will tell you how to get the pattern

 

[Dansouthcoast84]

rendersystems are you on the tools or a supplier, i am impressed with your technical info on the forum

 

[Render Systems]

Hi Dan Im a contractor been in the business 37 years now this is one of my websites with plenty of links to lime work and advice Lime Renders applied by craftsmen

 

[Dansouthcoast84]

Nice website rendersystems, always prefer rendering than inside works, and want get into it in a big way and experience the different systems an ewi. its getting the contacts and experience tho as thincoats and ive not used as much as id like

 

[Render Systems]

Just push the thincoat when your pricing thats what i do now, cant be arsed with monocouche renders now to much hassle waiting 4 - 20 hours for it to take up depending on the weather, then you have the nightmare scenario if rubbing up using lights that you miss a bloody 2mm spot and it sticks out like a sore thumb... thin coat all the time for me now unless its a renovation and lime is needed

 

[Dansouthcoast84]

I agree. The mono and krend alot of work.round here people want chdap.realy annoying.

 

[DannyMac]

So what does this polperro ripple look like?