Alone, our DOFF and TORC systems have the capabilities to remove some of the most stubborn substances and matter from stone and masonry. However, there are circumstances when they require some assistance – which is where Stonehealth’s own No.6HV and No.7s paint softeners come in.
When are paint softeners required?
Prior to any cleaning, preliminary trials take place to establish how many layers there are to remove and what these layers are comprised of. Typically trials are carried out in an isolated area of the site, and two or more sections – roughly six square inches each – are subjected to different forms of cleaning.
If the bare stone or masonry is not visible within a minute of using the DOFF alone, this indicates that paint softeners may be necessary to aid the DOFF. This tends to be the case if the coatings have been present for several decades, or if dozens of layers have been applied.
What do the paint softeners do?
Paint softeners are capable of dissolving multiple layers with one application, which can be done with a brush, roll, or spray. After being left to dwell for 12-24 hours, a DOFF clean is facilitated by the weakening of these layers and labour time is significantly reduced as a result.
All of this can be done without causing any damage to the structure of sensitive stonework, or allowing paint pigments to be drawn into the substrate.
What are the differences between each paint softener?
The differences between No.6HV and No.7s paint softeners come down to the type of coating that needs to be removed.
The No.6HV softener is ideal for the removal of plasticised and acrylic paints, as well as bitumastic coatings from stone, brick and most other building materials.
The No.7s paint softeners is used to remove oil and polyurethane-based paints, and varnishes from stone, brick, and wood – as well as most other building materials. Generally it is applied prior to a DOFF clean, but paint removal can also be achieved with a spatula if this is easier.