Originally Lime render but prev painted acrylic.....Help!

[AmandaC]

First post so fingers crossed......

We bought our bungalow from a deceased estate so no info on the house build etc was passed on so we have had to work it out for ourselves....

Anyway decided it needed a lick of paint externally. Stripped off Ivy, climbing Hydrangea ( suckers refuse to budge..... any tips ) and with Hydrangers came paint. Did finger thumb test and current layer of paint bends therefore I am told it's modern acylic paint.

However render appears to be lime render and original pink coat of paint under flexible peach paint appears lime wash so I am assuming some clever sod has painted modern paint on an originally lime washed and lime rendered house

Now we have a constant battle with damp and condensation and I am worried this is our problem.

How do I resolved this ? How on earth do I strip modern paint off very rough cast render so I can repaint with limewash and allow the house to breathe again.....

Many many thanks for taking the time to read this

 

[dcdec]

Probably have to be sandblasted or ice blasted which is less common and much less messy, job for a specialist company really. Be worth establishing if it definitely is lime render before spending the money. I don't get much lime render in my part of the world and someone may have to correct me on this but i've always understood it to be applied smooth, not roughcast which makes me think you need to check, could be wrong though

 

[ic1927]

Lime render can be smooth finished or roughcast. I'd be wary of sandblasting lime render in case of damage to the substrate, I would think that quartz sand is unsuitable, sandblasting can use other materials as well as sand though like silicone carbide and glass beads, perhaps this might be the way to tackle it. As dcdec says it's a job for specialists, seek advice from a reputable sandblasting company is your best bet.

 

[dcdec]

Thanks for clearing that up.

 

[AmandaC]

Here is what we know so far....

Bungalow built in the 1970's timber frame, concrete panels then render. Built on a hill so ground level one end nearly as high as 2 storey house other end so massive void under house.

Where exterior wall has blown at ground level render very thin but comes off in sheet like pieces, small fine cracks in p[laces but hairline very fine. Inside of render and whatever is under it very very pale almost white.

Original paint pink and when wet goes much darker colour where as peach paint ( second coat) does not change colour when wet and is bendy when flaked off.

How do I find out if Lime render or do we assume as timber framed and first paint was limewash then it probably is?

Is there any pics etc I can take that will help you more knowledgeable folk to diagnose it for me?

We have a real damp problem in my husbands office which is an extension approx 15 years ago and the walls appear to sweat and water literally runs down the inside? The whole house was wall papered but we are gradually removing it would that make it condensate more ?

Many thanks again

 

[ic1927]

Removing a small piece and sending it for a lab test is the surest way, petrographic analysis I think they call it. Some swear by putting diluted hydrochloric acid on the render and if it fizzes a lot then it's lime. Try asking on the plastering/rendering forum, the fellas on there would probably know more about this situation.