What type of Paint please?

[fallschirmjager]

I'm in the process of purchasing a historic building (not listed) called Brickhouse Farm. I'm assuming the building material of the house is in the name and looking at pictures of what I can see in the loft the gable ends are brick. The house is over 300 years old so I'm assuming the outside render and interior walls will be lime plaster based (is this correct?).

So this has me thinking. If the structure of the house is made of brick do I still require breathable paint on the exterior and interior as I am under the impression breathable paints are used on buildings made with wood/wattle & daub construction. Or is the breathable paint used to let the lime plaster breathe no matter what the main construction of the house is built with?

Thanks.

 

[Feltwell]

Hello,

is the breathable paint used to let the lime plaster breathe no matter what the main construction of the house is built with?

Essentially, yes. Breathable paint should be used no matter what the construction is, unless it's a modern cavity walled house. It's not to let the plaster breathe, it's to let the whole wall structure breathe.

As for your render - it could be lime based, it could be cement based. Many old buildings have been re-rendered in cement based renders within the last 100 years. It's definitely not a good idea, but it also doesn't *always* cause a damp problem. The same goes for gypsum plaster inside (the pink stuff!) - if it's been plastered with that in modern times, which is not breathable, the paint won't make much difference.

I'd advise getting yourself a good surveyor with a specialism in old buildings to do your survey, a lot of surveyors just don't understand how old buildings work.

 

[fallschirmjager]

Thanks very much. Funnily enough I was looking for an historic buildings surveyor online last night and one is based within 500m of the house.

Thanks again.

 

[Flyfisher]

Given that breathability is a big issue for period properties of all types, are there any circumstances where a NON-breathable paint can be a bad thing?

I’m sure there are areas of most period properties where a modern ‘plastic’ paint could be used with no problem because of reduced breathability, but given the wide range of caesium distemper and clay paints available these days are there any good reasons to take the risk?

In other words, would there be anything wrong with a general rule to always use breathable paints in period properties?

 

[Feltwell]

I don't think so, but it's more a case of assessing if past use by others of non-breathable paints is a bad thing.

Having said that I've used modern emulsion here in various places - on internal walls, ceilings or over previous impermeable finishes then I don't see the harm - it's readily available in an almost infinite range of colours at the local decorator's centre and it's relatively cheap and easy to apply.