Doff machine - masonry paint removal

[ChevronB19]

Live in a listed house, originally limewashed, but a previous owner has painted it with non breathable masonry paint, now in bad condition.

Local specialist (20 years plus experience in lime plastering/render etc) popped round today to give an outline quote to remove and replace the existing cement based render which is on about 1/5th of the house (rest is painted brick).

I might as well get things done right, so as well as render replacement, I’m considering stripping the existing non breathable masonry paint off the remainder of the house (you can see original lime wash below where it has peeled off), and he said the best/easiest way of doing it would be with a Doff machine, which essentially uses superheated steam. An example link below.

https://softwash-systems.com/shop/doff-steam-syste...

Has anyone got any experience of using these, or having someone else use them on their house? I wouldn’t be buying it by the way, and he doesn’t have one.

[Evoluzione]

It's a bit niche for a motoring forum. I have no experience, but it generally comes well recommended in old house restoration circles. Expensive, gentle and sympathetic.

[randlemarcus]

Partridge Exterior Cleaning on YouTube use steam fairly often, might be worth a watch, and maybe dropping him an email. And it annoys me internally that I find his videos quite watchable.

[wol]

Not sure what part of the country you are, but this chap loves his DOFF machine....

Looks to be very effective too.

https://www.instagram.com/lostmarblebuildingconser...

[smifffymoto]

Have a look at Thermatech.
Apparently the boss used to work for Doff and is very helpful.

[Leptons]

Following with interest. I have a red brick house which someone has painted with Red masonry paint. So far tried brick acid and a 200 BAR Pressure Washer without any Joy!

[dmsims]

Having suffered I feel your pain

I ended up using mechanical methods and Peel Away

It cames off in sheets with green mould growing underneath

What sort of condition is the render in and is it hollow if you tap ?

[M1AGM]

I have a man coming next month to use one of those machines on some external brickwork the ‘builder’ left splattered in mess.

When he popped by the other week he said it was very sweaty work as he’s been doing the same on a mate’s house.

[Instant Cynicism]

The answer really depends on how your house is constructed. If you're sure it's a concrete render the proposed approach may be fine. If it's really a lime render you may well end up doing more harm than good. My Grade II listed cottage had a non-porous masonry paint applied to the lime render causing all sorts of issues. Took me 6 weeks to remove it using progressively more aggressive techniques (Peel away, heat gun, wire brush attachment...)

I don't think the previous owner has done you any favours by applying a limewash to a concrete render - I'm not surprised the masonry paint is peeling off.

[Aluminati]

We have used it in commercial applications, but it was for stone cleaning on older buildings. ( Doesn’t damage anything)

Never seen it used to remove paint though.

[ChevronB19]

Instant Cynicism said:

The answer really depends on how your house is constructed. If you're sure it's a concrete render the proposed approach may be fine. If it's really a lime render you may well end up doing more harm than good. My Grade II listed cottage had a non-porous masonry paint applied to the lime render causing all sorts of issues. Took me 6 weeks to remove it using progressively more aggressive techniques (Peel away, heat gun, wire brush attachment...)

I don't think the previous owner has done you any favours by applying a limewash to a concrete render - I'm not surprised the masonry paint is peeling off.

Sorry, just to clarify. A small area of the house has painted cement render which is cracking. This will be removed and replaced.

The remainder of the house is plain brick, limewashed, with non porous masonry paint over it. It’s this area on which I am proposing using a Doff machine on. I.e. there is no area which is limewashed concrete render.

[astroarcadia]

I would get some sample panels done before committing to a particular system.

https://www.restorative-products.com

Jamie Fairchild is the man who developed Thermatech and has incredible knowledge.

[Tin Hat]

We do a lot of this type of work, we often end up using a combination of Thermatech and peel away to remove modern paints, it can be quite time consuming if the paint has stuck well.

If you are planning on applying a new decorative finish, then I can warmly recommend Keim mineral paints - Typically expensive, but faultless in our experience

Good luck with it!

[ChevronB19]

Tin Hat said:

We do a lot of this type of work, we often end up using a combination of Thermatech and peel away to remove modern paints, it can be quite time consuming if the paint has stuck well.

If you are planning on applying a new decorative finish, then I can warmly recommend Keim mineral paints - Typically expensive, but faultless in our experience

Good luck with it!

Many thanks!

[dmsims]

On the paint subject this has been on for 3 years

https://northernpaintsandcoatings.co.uk/lp/breatha...

[hidetheelephants]

What's the cost per sqm roughly? I have multiple layers of paint in varying stages of peeling off and it looks st, DIY with a wire brush in the angle grinder doesn't appeal much.

[2Btoo]

I've used a Doff system quite a lot to remove graffiti from very historic masonry, on an old church. The Doff system is effectively a water boiler which supplies a commercial jetwash pump with very hot (boiling and beyond) water. It works for our purposes by melting the graffiti paint and allowing it to be washed off without damaging the underlying stonework; to use a jetwash system alone would damage the stone and chemical cleaners are a no-no for conservation and heritage people.

It works well, but it's a faff to use. The whole lot (just about) fits in the back of a large crew-cab 4x4 (along with a large water tank and a smaller kerosene tank) and it takes quite some time to set up, although once running it runs well. How it would work removing larger areas of paint from older stone or brick I don't know but I suspect it would do it quite effectively.

[Terminator X]

We used it to clean the facade of a building in Mayfair being renovated. Seemed to be just a very hot water^ jet wash from what I could see.

^possibly steam yes

TX.