b'spectrum scienceWhite over drawdown swatches in black and white until full coverage is obtainedtop tipdid you know? Reseneright: The Resene Technical team applies layers of each topcoat colour to scientifically determine which varishade is the right choice. Then, the The opacity of a paint is its ability to block light fromtopcoat colour is applied over six new drawdown swatches that haveAlways allow the paint to dry before judging the paint finish. been undercoated in white and the six Resene varishade tones until getting though and the hiding power of a paint is itsthe coverage is consistent with the original full coverage swatches. TheMany paint finishes will settle down after the initial drying phase.ability to adequately hide the surface it is applied to. varishade tone that produces the best match with the fewest topcoats applied over it is then chosen as the preferred undercoat. For this test,Calculating proper coveragetwo topcoats of Resene Key Largo have been applied over drawdowns inWhen it comes to calculating the right quantities to get you solventborne, who is applying it, the application method, the toolsResene Black and Resene White. opaque coverage on the various components of your project, used, the number of coats, the ambient temperature and humiditythesurfaceyouareapplyingyourcoatingtoisasignificant and even the sheen level. factor. For example, porous surfaces will always absorb more of It probably goes without saying that waterborne products andof rollers. Just like the other coverage factors weve mentioned,what gets applied to them, so they can require additional paint solventborne products are made up of different raw materials,the Resene Technical team has put plenty of thought into this. in order to achieve full opacity of your topcoat colour. Materials but the same size tin of a waterborne paint with a higher glossWhen investigating coverage-related complaints, Resene foundlike corrugated steel also require far greater quantities than a finish will have less pigment in it than one with a flatter or mattemost occurred because a painter armed with a microfibre rollersimple surface calculation would suggest because you have to finish. When you think about it, it makes sense, because a glossierhad spread the paint too thinly, causing the colour underneath totake into account that all the vertical components also need to be product has to be manufactured with more ingredients to make itgrin through. The act of applying paint with a brush results in theadequately covered. Extrapolate that over the scale of something glossy, so there will be less room in the tin for pigment. However,formation of valleys and ridges within the paint film and pimpleslike a factory roof, and its going to need far more than your youll still want that product to give you an opaque finish withoutand dimples (or orange peel effect) in a rolled film. Thinner film inpainter making a quick run to the Resene ColorShop to grab an having to lay on a bunch of extra coats. the valleys and dimples would draw the eye, creating the impressionextra tin. A good rule-of-thumb for calculating the quantity of ThankstotheReseneTechnicalteamsvigoroustestingof poor coverage. The ridges and the pimples, on the other hand,roof paint required is to add approximately 40% of your projects and high-quality standards, paints in the Resene Total Colourwere excessively thick and afforded more hiding than required. footprint area to allow for roof pitch, corrugations and soffit System generally have the same coverage in terms of hidingBeforetheadventofthemanyadditivesavailabletoday,overhang. However, be aware that trough section roofing can powerno matter which formula you chooseso long as thewhich allow paint chemists to dial in precise profiles for paint,require significantly more.product is applied according to instructions on Resenes dataeverything from how well you controlled your applicator to theFormostsurfacesthough,estimatingpaintisfairly sheets.Thisincludesrecommendationsforthesurfaceareabristle types or lengths used in brushes to the nap lengths andstraightforward math. You simply need the surface area of what that the product should cover, but also about the environmentalfibretypesusedinrollerswerefarmorecritical.Microfibrewillbepainted(excludingdoorsandwindows),thespreading conditions when the paint is applied.rollers do give a very uniform film thickness, but they can make itrate of the product and the number of coats needed. Divide the When paint is cold, it has a higher viscosity, so there is a chanceeasy to overspread the paint. This led Resene to design paint withmore and better-quality pigment and resin. Cheaper productssurface area by the spreading rate and multiply those results by that it will be applied at a higher wet film thickness than therheology properties to stop this happening in instances where thewith larger spreading rates usually include more water, whichthe number of coats and you will have the adequate quantity of conditions it was tested under. Conversely, the paints viscositywet and dry film build was insufficient for complete hiding, saysmeans you are stretching the pigment further and will ultimatelyproduct required for proper coverage over previously painted or is lower in warm weather and therefore has more tendency toResene Senior Chemist Greg Percival. mean you will need to apply more coats to get decent coverage.undercoated walls that are in good condition. However, its always spread further, which can result in poorer hiding if it is spreadA good test to ensure paint is not overspread is to consider theOr the spreading rate may be overstated and youll find you needsmart to round up to accommodate for a small amount of wastage too far. High humidity slows down the drying time of waterbornearea you need to cover. One litre of interior paint from Resenemore to cover the area than planned. and in case damage occurs as the project proceeds that requires paints, which could allow overspreading due to the paint notis usually enough to cover around 12 square metres of wall space.touch-ups.Tomakethingseveneasier,usethefreeonline drying as quickly. While this may not make a huge difference on aIf your wall is 6 square metres, then you should use around 500top tip Resene Resene Paint Calculator at www.resene.com/paintcalculator.smaller project, its important to consider these factors for largermL per coat. If you find you are using a lot less product, it is being projects to make sure you achieve the right coverage with theabove: Resene developed six different grey varishade colours (which are numbered 1-5 and 10 to indicate their greyness, rather than named) which allow forspread too far and you wont get opaque coverage. It is alwaysAlong with using premium paint, itsKey Largo top tipright number of coats. the perfect level of contrast between your undercoat and your topcoat colour. Background in Resene Acrylic Undercoat in Resene White with brushstrokesbetter to apply two coats of paint at the right spreading rate thanimportant to use high-quality application in (from left to right) Varishade 1, 2, 3, 4, 5 and 10. Choosing the right varishade for your chosen topcoat is easy: it is recommended through the Reseneapplying more coats to add the paint that should have alreadytools if you want a high-quality finish. TheWhen specifying, remember to include the cleaning products Tools of the trade e-tint colour formulation system. Where an undercoat is recommended for a Resene colour, youll find it noted on the colour card with uc. Simply specify been on the wall. Not only does this overspreading cost a lotbrushes, roller sleeves and painters tape availablerequired to properly prepare your project prior to coating. For You may have guessed that applying paint with a brush versus aa Resene undercoat, waterborne or enamel, for your project and the Resene ColorShop team will select the appropriate varishade for your topcoat colour. more in terms of time, the product may not perform as intended. at Resene ColorShops help you apply the paintexample, a complete roof paint system typically requires surface Reseneroller will result in a different wet film thickness of paint beingResene Resene Resene Resene Resene Resene Beware of cheap products that have overly large spreadingcorrectly so that you dont waste time and paintBlack preparation using Resene Roof and Metal Wash, one coat of primer applied, but it can also differ between types of brushes and typesVarishade 1 Varishade 2 Varishade 3 Varishade 4 Varishade 5 Varishade 10 rates. Premium paint provides better coverage because it containson reapplication or unnecessary touch-ups. and two coats of topcoat at the recommended coverage rate.40 blackwhitemag.com blackwhitemag.com 41'