Breathable paint over existing layers?

[Hazelbarn]

Hello all,

Looking for painting/decorating advice with a late 16th century black and white timber frame farmhouse. I am looking to paint the whole house initially just in white to tidy up and then will go back and add colour to each room more thoughtfully as we settle in. I am already feeling overwhelmed at just choosing a white paint!

Surfaces inside are mixed; lathe and plaster squares, hardboard covering and brickwork. I’m not up to stripping any paint off right now (long term is this advisable?) so not sure if it is worth using a breathable paint? And if it is, I can’t afford to do everything in Auro or the like, are there any water-based emulsions better than another? I know they’re not as breathable as clay paints etc but hoping for a pragmatic/not too house destroying solution as so much to do?

Also – what to put on any window frames and sills that will be sanded back and painted? Are Auro etc good for these?

Specific problem: There is flaking paint on brick walls in several of the kitchen rooms, and have been told there is probably salt in the walls. Is there anything we can put on the walls that will help make the walls a bit more hygenic? – so we don’t get flakes in the food! Or any general thoughts? Will upload photos. These were all painted in Auro about 6 years ago.

Many thanks
Hazel

 

[Cubist]

Hi Hazel and Welcome to the Club,

If you have salt appearing on internal walls this can indicate that water is penetrating from the exterior so first order of business is to check the outside in the vicinity of affected walls to see if there are any damaged/ineffective gutters,gaps around window and door frames, any roofing immediately above that may have loose/broken tiles or damaged flashing, damaged or blocked drain pipes and drains and soil levels above any damp course. Another thing to look out for would be any cement render or plastic paints that may have been applied to the outside of the affected walls. You will need to address any such defects before dealing with the internal problem. There are treatments available that can be used to neutralise the salt and stabilise the plaster ahead of painting indoors check out this link;
https://www.diydoctor.org.uk/projects.ht

As a first thought for a cheap and cheerful white only solution you might consider using a self mixed lime wash using Lime Putty as a base. I used this on the exterior of our place earlier this year. It takes a few coats to get a good coverage and if you find a way to get a consistent, i.e. not patchy, finish let me know please.

Depending on what paints the previous owners have used internally, washable emulsions and waterproof as some do, you may need to strip the internal walls back to near plaster to get the house breathing properly - or you may find that condensation will become a breeding ground for moulds of one sort or another.

Breathable paints are typically more expensive but with a little digging you may be able to find cheaper interior paints that have a low SD Value (check this link for more info http://cornishlime.co.uk/information/breathable-paints-explained/)

Hope this helps but I'm sure you'll be hearing from many others soon.

Keep us posted on progress please.
Cubist

 

[Feltwell]

Just to bump your thread for you, as a new poster they often appear down the list and get a bit lost - Edit - Cubist beat me to it! :wink:

If your existing finishes are impermeable then putting another impermeable emulsion over the top for now won't make things any worse, just gives you another layer to strip back when you do come to do it "properly". Having said that in rooms here where there is modern emulsion on the walls with no issues I've gone over with modern emulsion again, if it ain't broke don't fix it.

Joinery - I've switched across to Bedec MSP water based paint, of which there are a few other fans on here. Seems good stuff but I've only been using it for a couple of years.

Paint falling off bricks - that is quite dramatic, isn't it? I'll leave that one for others to comment on but I'll be interested in thoughts, as I've got a cellar that's been painted in a modern impermeable cellar paint by previous owners, that's flaking off badly in areas of damp. I'll scrape that off but I don't want to strip all the sound stuff off and want something to cover it all, so limewash is out. I've heard good things about silicate paints on masonry in the past.

 

[Cubist]

Forgot to mention. You only need to worry about breathable paints for walls that form the exterior of the house. Any internal walls between the different rooms you can use anything you like. As far as the woodwork around windows and exterior door frames is concerned if the timber is sound and there are no breaks in whatever has been used to caulk them against rainwater then I would not worry too much about the interior paint - personally I prefer an eggshell finish but at the end of the day I simply do as I'm told.

 

[Hazelbarn]

Thank you so much for those replies, just the kind of ideas I was hoping for! Will be off checking out your recommendations, thanks. And yes, I think there IS a problem with the guttering in one area, which can't be helping. Will do some investigating, as you say. Hazel

 

[Abi Cott]

Sometimes upgrading your paint isn't as much as you think, because better quality paints often have better opacity.

If one paint costs £20 a tin and you need 3 coats, and the other costs £30 a tin but you only need 2 coats, which is cheapest

 

[Me!]

It's hard to be sure from a photo, but in your third picture the brickwork on the left looks to me to be actually wet rather than just damp?
Is that a chimney stack? If so, has it been bricked up at the bottom and left open at the top for rain to still get in?

 

[Hazelbarn]

Going to check the chimney as well as guttering... thank you!