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Published in Les Goring, Residential Surveying Matters and Building Terminology, 2023
Water-based paints used externally: These modern paints are water-soluble, but become water-resistant when they dry. As a binding agent, different ingredients are used in the paint’s manufacturing stage. These include acrylic, vinyl, alkyd or polyvinyl acetate (PVA), giving water-based paints many advantages over traditional oil-based paints. For example, they emit far fewer health- and environment-damaging VOCs (volatile organic compounds) than oil-based paints – and the painting equipment used (brushes, containers, etc.) can be washed out more easily in water. Water-based paint (not emulsion) is also more compatible with the natural, moisture-content characteristics and movements of timber. Thereby, it is reckoned to last longer than oil-based paints, meaning that maintenance periods can be at least doubled from the traditionally recommended four years to eight or ten years.
Internal elements
Published in Roy Chudley, Roger Greeno, Karl Kovac, Chudley and Greeno’s Building Construction Handbook, 2020
Roy Chudley, Roger Greeno, Karl Kovac
Paint can applied by: Brush: the correct type, size and quality of brush needs to be selected and used. To achieve a first-class finish by means of brush application requires a high degree of skill.Spray: as with brush application a high degree of skill is required to achieve a good finish. Generally compressed air sprays or airless sprays are used for building works.Roller: simple and inexpensive method of quickly and cleanly applying a wide range of paints to flat and textured surfaces. Roller heads vary in size from 50 to 450mm wide with various covers such as sheepskin, synthetic pile fibres, mohair and foamed polystyrene. All paint applicators must be thoroughly cleaned after use.The main objectives of applying coats of paint to a surface are preservation, protection and decoration to give a finish which is easy to clean and maintain. To achieve these objectives the surface preparation and paint application must be adequate. The preparation of new and previously painted surfaces should ensure that prior to painting the surface is smooth, clean, dry and stable.
Automotive finishing and re-finishing
Published in Andrew Livesey, Alan Robinson, The Repair of Vehicle Bodies, 2018
The damaged area should be levelled up as previously described and the whole of the surrounding panel wet flatted with P400-grade paper. Following drying and tacking off, the panel should be sprayed with primer surfacer or filler and flatted with P600-grade paper. After drying and tacking, the colour coats are applied. The function of this final coat of surfacer is to equalize solvent penetration from the finishing material. Surfacers and fillers are more porous than enamels, and when the surrounding panel is sprayed with the finishing colour only the repaired area can be detected by a slight variation in colour and texture. Where costs permit, a coat of sealer could be applied prior to the finishing colour. Light burnishing and polishing of metallic finishes can be done after overnight drying in the case of acrylic and cellulose-based materials. With the slower drying synthetics this process is best left for about 4 days to allow for complete solvent evaporation and to give the paint film time to harden off. When using two-pack materials, burnishing can be carried out after 16 hours at a workshop temperature of 15 to 20°C.
Investigating the Effects of Climate Change on Material Properties and Structural Performance
Published in Structural Engineering International, 2022
Andre Orcesi, Alan O'Connor, Emilio Bastidas-Arteaga, Mark G. Stewart, Boulent Imam, Katerina Kreislova, Franck Schoefs, Olga Markogiannaki, Teng Wu, Yue Li, Abdullahi Salman, Lara Hawchar, Paraic C. Ryan
The corrosion of steel structures begins after degradation of corrosion protection coatings that have been applied on them. Low alloyed steel structures are protected against corrosion by various types of protective coatings—metallic, organic or duplex. The most frequently applied metallic coatings are various types of zinc or zinc-alloyed coating. The zinc coatings are more sensitive to the effect of high humidity than steel. Unfortunately, there is no model for service life prediction of paint systems. A DRF for coatings has been suggested in the past37 but the effect of climate change on the deterioration of coatings has not been investigated.38 Research efforts for developing deterioration models for assessing the effectiveness of coatings on structural resistance can be found in Ref. [39]. Practical experience shows that the maximum service life of paint systems is 25 years in contemporary conditions. In addition to the climate and pollution parameters, the service life of paint coatings is significantly affected by UV radiation. Thirty years of satellite data show that the amount of ultraviolet (UV) radiation reaching the Earth’s surface has markedly increased over the last three decades.40 Most of the increase has occurred in the mid-and-high latitudes, e.g. at latitude 32° the UV radiation has increased by 6% on average since 1980. These changes decrease the service life of paint coatings, but the amount of the degradation increase is based on laboratory data only.41
Bio-Based Composite Footbridge: Design, Production and In Situ Monitoring
Published in Structural Engineering International, 2019
Rijk Blok, Joris Smits, Rafail Gkaidatzis, Patrick Teuffel
Concerning the protection of the composite laminate from moisture, UV light and other harmful environmental factors, the application of a layer of coating has been essential. Paint typically consists out of solvent, pigment, resin (binder) and additives. Negative environmental impact of paint is mostly linked with the emission of volatile organic compounds (VOCs) during the drying phase, causing excessive formation of ozone, a highly toxic component which increases human health risks. To reduce these harmful emissions, less-VOC or no-VOC products are currently becoming available in the market.
The Concept of Historical Aluminium-Pigmented Anticorrosive Armour Paints, for Sustainable Maintenance of Ferrous Heritage
Published in International Journal of Architectural Heritage, 2022
One of the most commonly cited reasons for historical linseed oil paints falling out of use is their relatively long drying times, which differ considerably from modern paints. On the other hand, the drying time for alkyd-based paints is often stated as 24 hours. Most traditional architectural painters do not consider the drying time of linseed oil paints to be a problem, nor do the stakeholders involved in the care and management of our ferrous heritage (Källbom 2018). The drying time of linseed oil paints is easily accommodated by proper planning of the work. By carefully sequencing the work, other interventions can be undertaken simultaneously, or on other objects, during the drying time. The drying time is usually around 1 day with some extra days for hardening through the paint layer, before the next layer is applied. Trials undertaken using historic recipe VOC-free armour paints (with quarter tung oil binder) and primers of aluminium-triphosphate (high-temperature linseed oils) have been undertaken by the author since 2017 at Gothenburg University in Mariestad, and are ongoing. The findings have shown that, by adding even a very small concentration (≥0.3 wt %) of drier solution (a combination of primary, secondary and auxiliary siccatives), the drying time of a 40–50 µm paint layer can be reduced to about 12 hours. If the final armour paint layer (with a high content of stand oils) requires long drying times, this is usually of no practical importance. The quality of the drying oils has been found to influence the drying capacity of the oil varnish. Already in 1867, Mulder distinguished between rapid and well drying capacity (Mulder 1867, 165). Indeed, the drying rate is not in itself the most crucial factor. The drying needs to take place through the entire film thickness, and the resulting paint film must be elastic and dense. Incorrect use of driers or siccative additions could also lead to premature failure of the paint films (Stenberg 2004; Strömberg 1948).