What is the difference between acrylic and enamel?
Acrylic paints are composed of synthetic resins (usually acrylic or vinyl acrylic) and pigments dispersed in water. Acrylic paints dry by evaporation of the water causing the particles of resin to fuse together forming a continuous coating. Acrylic has excellent adhesion, colour and gloss retention, long-term flexibility, and toughness. They are also easy to apply, clean up in water and safe to use. Most acrylic paints must be protected from freezing and applied at a minimum temperature of 10 degrees C Enamel or enamel-based paints are coatings produced by reacting a drying enamel acid with an alcohol. Drying occurs by the evaporation of a solvent; curing of the resin occurs by oxidation. The more enamel there is in the formula, the longer it takes to dry, the better the wetting properties, and the better the elasticity. Enamels can be used as interior or exterior trim paints, machinery enamel, or durable wall finishes. Top quality enamel-based paints also offer excellent adhesion, but there’s a trade-off. With the passage of time – and depending on the substrate, weather conditions and the particular paint – enamel-based products can yellow and become brittle. In extreme circumstances enamels can begin to crack in just a few years. Enamel coatings should not be used directly on masonry, galvanized metal or other alkaline surfaces to avoid saponification.
Acrylic vs. Enamel Comparison
Colour Retention – enamel (Not as good as acrylic; more likely to chalk and fade in sunny exposure. Acrylic (Superior resistance to chalking and fading, especially when exposed to bright sun.) Does not yellow like enamel.
Ease of Application – enamel (More difficult to apply due to greater “drag,” and need to keep a wet edge.) Needs to be washed up with smelly and unhealthy solvents. Can not be applied with out an undercoat. Usually takes 24 hrs between coats, 8 or so hrs to be touch dry and 3-5 days to be case hardened or fully cured. Acrylic (Goes on smoothly and evenly, with less brush drag.) Much easier to apply and can be recoated with out the need of an under coat. Can apply more than one coat per 24 Hrs. Only takes 24hrs to be totally case hardened or cured.
Mildew Resistance – enamel (Vegetable enamel base can provide nutrients for mildew growth; most products contain a fungicide to minimize growth.) acrylic ( Less inherent tendency to grow mildew; anti fungicide additives discourage mildew growth, help maintain fresh appearance.)
Versatility – enamel (Can be used on most substrates, but for new concrete, stucco and other masonry, sealer or pre-treatment is required; should not be applied directly to galvanized metal.) Enamels main use these days is on trims, windows etc. acrylic (Can be used on wood, concrete, stucco, brick, galvanized metal, vinyl siding, aluminium siding, etc. (Recommend primers as appropriate))
Odour – enamel (Noticeably more odour than acrylic.), acrylic (Very little odour; non-combustible.)
Cleanup – enamel (Requires hydrocarbon solvents.) Turps, acrylic ( Simple water cleanup.)
Drying Time – enamel (Eight to 24 hours normally), acrylic (One to six hours, permitting quick recoating.)
Is acrylic better than enamel?
This really depends on the substrate ( surface to be painted ), protection needed for that substrate and personal choice. In each circumstance it could be either. Quality acrylic paints are very flexible, so their adhesion continues to be excellent, even when temperature changes cause the substrate to expand and contact. In turn, this helps acrylic paints resist cracking. Because of the strength, flexibility, colour retention, low VOC levels and ease of application, acrylic coatings are widely accepted as the only choice as a coating in most circumstances and especially on large areas.
Even so, top quality enamel paints can be the better recommendation in certain repaint situations. The first of these involves painting over heavily chalked surfaces. Enamel-based paints tend to adhere better than acrylic paints to substrates that have chalked excessively. Of course, it is still important to properly prepare the surface by removing as much chalk as possible before painting. The second instance in which a top quality enamel-based paint is to be preferred is when repainting a surface containing multiple (four or more) layers of enamel-based paint. In the latter case, the “elastic” acrylic paint can sometimes accelerate the adhesion loss of embrittled enamel paint. In this situation, you may want to play it safe by using a quality enamel-based product as a sealer or undercoat at least.
Of course, durability is just one characteristic that customers look for when buying paint. Colour retention is important to many people, while others want a product that is easy to work with. Enamel coatings do have their place as a primer/sealer and as a hard, durable coating for various substrates.
It is safe to say that these days the use’s for enamel paints in a domestic situation are becoming more and more limited. Enamels are really only a constant choice for primers and undercoats, or in rubbing situations like double hung windows and commercial walls. An example of this would be the walls of a public toilet.
Do I need one coat or two finish coats?
The Sydney Painting Professional always recommend two coats over a properly prepared and primed substrate. By using a two coat system the applicator and the client can be safe in the knowledge that the finished surface will be uniform and correct in appearance. A one coat system will always show untidy edges here and there and will not have uniform colour coverage. A two-coat finish is required for all Sydney Painting Professionals written warranties.
Do I need a full undercoat/primer when I repaint a. interior b. exterior?
Interior- When repainting an interior surface and if using a similar type of coating i.e acrylic over acrylic, Than the answer is no. Enamel over enamel areas are different. In this situation the areas must be correctly prepared and undercoated always. In both instances areas that are stained or damaged should be correctly prepared and at least spot sealed or spot primed with the proper primer or sealer. An enamel based sealer or primer can be over coated with either an acrylic or an enamel product. If repainting enamel over acrylic or acrylic over enamel, a primer should be used as a barrier coat to promote adhesion and to prepare the substrate back to a sound and compatible surface. Normally this would be an enamel based primer.
Outside- The same rules hold for exterior repainting. If there are areas that must be prepared for recoating such as peeling paint or mildew stains, and the preparation takes you down to a bare substrate, priming is necessary to seal the substrate in preparation of painting. Enamel based primers penetrate the substrate surface and form a tight seal prior to a acrylic or enamel based paint topcoat. Again, if a barrier coat is necessary for between coat adhesions, an enamel primer does a great job of sealing over the previous coating however, current technology is making great advancements in the availability of acrylic primers and sealers that soon will do the same task as successfully.
Which is better spraying or brushing/rolling?
The type of application process is contingent upon the type of coating being used, the area to be painted and the availability of the proper equipment. Both acrylic and enamel based paints can be applied by either manner.
In spraying, the proper tip size and suggested air pressure needs for the coating per the manufacturers instructions, must be met before application can commence. Spraying of coatings is best suited to large, open, unoccupied, or areas where over spray is not an issue. Coatings that are sprayed normally give a level substrate a smooth finish with the absence of brush or roller marks. Proper training in spray safety and application techniques by qualified personnel is strongly suggested.
Brushing and rolling is best suited to more confined and closed in areas. With proper instruction and technique, brushing and rolling applications provide fast complete coverage of substrates. The choice of a roller cover or brush is dependent on the type of coating being used, the texture of the surface, and the size of the area to be painted. Brush and roller application can be used to get to small, intricate areas not accessible
What is the advantage of spraying?
Spray application is a production oriented process. Large areas can be coated at a rapid rate of speed. Spray application of enamel coatings leaves a smooth, shiny, continuous appearance.
Why do I get cracks in the corners and screw heads popping in my Plaster board?
The largest culprit in this instance is the settling and movement of a substrate. As this occurs, less flexible areas, such as the Plaster board tape in a corner or a screw will not shift or flex as this movement occurs. By using a flexible acrylic caulk and paint, some of this surface destruction can be avoided or masked. All screws and the like should always be counter sunk below the surface and filled with a flexible filler before applying
Why do I get cracks where my trim (skirting boards, window frames, door frames, Architraves, etc.) meets my walls?
Again, settling and substrate movement cause this cracking and separation between a wall and the attached trim. As discussed earlier, using an enamel based paint will also show these cracks as this movement takes place and the coating breaks. Application of a generous bead of a flexible, acrylic caulk in the void between the wall and trim board before painting will allow for some of this movement to be absorbed. Also, by using acrylic coatings on this area, more flexibility will be allowed as settling and shifting occurs.
Why do my eaves always peel?
There could be several reasons for the peeling of paint in an eave area. Let’s start with some of the more common issues. We will focus on the substrate of wood since it is a very common building material for eaves. A structural moisture problem could be an issue with regard to peeling paint. If large amounts of moisture are trapped under a coating, eventually the coating will fail. Acrylic paints do allow some passage of moisture through the coating but do not protect from a structural leak problem from say backed up gutters, internal leaks or improper flashing placement.
Another problem that may be causing this peeling is the type of product used in construction. Fibro cement sheeting for instance often becomes dusty or dirty prior to being coated and if not cleaned initially then following coats of paint may peel in time. During repaints the surface must be rid of all dust, dirt, and mildew and any loose paint must be removed and sanded to a smooth finish. Any surface contamination will limit the adhesion of a coating. Spot priming any bare or stained areas with an enamel primer is required for proper adhesion.
Use a quality 100% acrylic coating designed for the exterior to coat the entire area. A good rule of thumb before applying a coating to a substrate is to do so on a surface that is clean, dry and dull. Follow this in all situations and your coating projects will result in far better results.
How do I prep my deck?
I am going to assume that this deck is wood. If it is new pressure treatedwood or for any wood surface, it is time to coat the deck when the wood is able to absorb water. To determine if the surface is waterproof, splash water on the surface. If the water is absorbed and the surface becomes noticeably darker, the surface is not waterproof and it is time to prepare and coat the deck. If the liquid “beads” up on the surface, allow the wood to weather longer and then check again. Once it has been determined that the deck is ready to be coated, clean the surface with an appropriate cleaner. If the wood has weathered and is greying, a cleaner that is specially formulated to clean and brighten the wood should be used. Follow the manufacturer’s directions when using this type of cleaner. Rinse the surface thoroughly and allow 2-3 days, depending on the weather,
I have some dry rot on my window sill — can you just patch it?
Patching this dry rot would only be a temporary solution to a much larger underlying problem. This substrate is already weakened by the fact that it is rotting. Adding a “patch” will only aesthetically fix the problem. The wood will continue to rot and fall apart. The concern is that too much moisture on this surface is causing this rot problem. Fix the structural problem such as improper water flow, or a flat surface where water pools, etc. and you will have greater success at protecting this type of surface area. Properly priming a new wood surface with an enamel primer prior to installation will help seal the surface. After the window sill has been replaced, caulk the appropriate areas to keep destructive moisture out and topcoat this with a strong, 100% acrylic exterior coating.
How do I repair and prevent the cracks that keep occurring from the ends of wood facia boards?
The cracking that you are experiencing on your fascia boards is caused by moisture entering the substrate. The moisture causes the wood to expand and contract as it enters and leaves the wood. This action stresses the wood and the results are the unsightly cracks at the ends of the board. To remedy this problem, remove all the loose and peeling paint on and around the affected area. This can be accomplished with a scraper or wire
How do I stop knots from bleeding through?
To stop knots from bleeding it is necessary to seal them with a shellac based primer, metholated spirits based sealer or an enamel based primer. Another option is to remove the knot and fill the hole with wood putty. Prime the patched area after it has dried and topcoat with a good quality acrylic or enamel based paint.
Is washing with water adequate for cleaning a surface to be painted?
Water alone will not remove most contaminants. To assure that you have a properly prepared surface use a mild detergent such as sugar soap or house hold bleach. Mix the cleaner according to label directions and apply to the surface. In some cases, such as severe chalking, it may be necessary to scrub the surface with a stiff brush before rinsing with water. For less severe cases, apply the detergent with a garden type sprayer and rinse thoroughly with a garden hose and nozzle or a 1500 PSI or less pressure washer.
How do I prep my peeling window sills?
First remove all the loose and peeling paint by scraping and/or wire brushing. Sand any exposed wood to a fresh surface and prime all bare or exposed areas. Fill any imperfections with wood putty or an appropriate fuller. Allow the fuller to dry according to label directions and sand smooth before spot priming these areas with an enamel base primer. Allow to dry and topcoat with good quality enamel or acrylic based paint.
Who has the best paint?
The key is to use quality paint from the manufacturers premium range, regardless of the manufacturer. In the realm of paint, there are various grades of quality and in order to be classified as premium paint then these paints require a GPC or Government Paint Committee Number to correctly identify them as being approved. Quality paint costs more, with the justification that it also lasts longer. But what proof is there that quality paint really is the better buy. This question is answered all the time by looking at such things as binders, pigments and additives. Quality paints have better binders. Quality binders cost more then binders of less quality. The type of binder and amount used affect everything from stain and crack resistance to adhesion. Several polymer types are used as binders for acrylic paints. Enamel paints usually have a drying enamel or modified enamel, called enamels, as their binders. Of the two, quality acrylic paints with 100 percent acrylic binders are especially long lasting. They are also more expensive. Typically speaking, quality paints have more prime than extender pigments. Prime pigments are good hiding pigments, while extender pigments provide bulk at low cost. The most common prime pigment is titanium dioxide, a white pigment found in both enamel and acrylic paints. It’s is expensive and is imperative for good opacity or film hiding ability. Quality paints also have more additives. Additives are included in paint to provide desirable properties. They might make the paint easier to apply, for example, or give it protective properties. Fungicides are an example. Lower cost paints take out some of these additives to save money. All of these benefits save time and money in the initial
How warm does it need to be to paint?
Most manufacturers recommend that oil and water based paints be applied when ambient and surface temperatures are above 10 degrees C and below 35 degrees C. Solvent based paints get thicker in lower temperatures making them harder to brush and slower drying. This can result in runs, sags, dulling of the finished coating and wrinkling on vertical surfaces as well as using more paint than needed. Below 10 degrees, acrylic paints also dry more slowly, especially when high humidity is present. This hinders coalescence, which can lead to poor film forming, lack of surface adhesion and premature paint failure. Some acrylic paints can be applied at lower temperatures. These specially formulated products contain coalescing agents that help in film forming during lower temperatures. Another thing to consider is the amount of daylight. When the days are short, there is less daylight available to help in drying. If you are using an oil based paint, which dries by oxidation, daylight is especially important. So, be sure to paint early in the day so that light is present to help in the drying process. Dew is another weather-related phenomenon to consider. Humidity affects the drying time of all paints. This is due to the added weight that the air takes on with the extra moisture present. The problem this creates is that by making the air heavier it is also making it more difficult for the accelerators in the paint to cause evaporation and subsequent drying of the paint. Most manufacturers recommend that at least two hours be allowed for paint to dry before sunset if cool temperatures and heavy dew are expected. Keep in mind that cooler temperatures will extend the time before the paint reaches serviceability or hardness. An enamelled door requires more time before it can be closed without sticking to the jamb. A clear coating applied to a deck will need more time before you can walk on it. Primers require more time before top coating. Knowing this may help you as work on your painting chores in the spring or fall.
Is caulking necessary on the exterior?
Yes, caulking is necessary on the exterior of your home. It will aid in preventing moisture from entering the substrate and causing premature paint failure. First remove any old or cracked caulking as well as loose and peeling paint from all areas to be caulked. Caulk all the vertical butt joints where your weather boards meet other boards and where all beadings and the like meet other edges. Never caulk the horizontal joints of your weather boards, this can cause moisture to be trapped behind the boards and result in premature paint failure. Other areas requiring caulk are around window and door frames as well as any area where a gap is present that will allow moisture or insects to enter. If the gap is deeper than 8mm use filler, such as a caulking rod to fill the gap before caulking. Allow the caulk to dry according to label directions before painting.
When I caulk, do I need to take out all of the old stuff?
Yes, caulking over old caulk can result in premature failure of the fresh caulk. Caulk gets the best adhesion when applied to a clean, dry substrate.
Why do I get black stuff (mildew) on my fibro sheeting?
If you notice that the fibro sheeting on your home is beginning to look dirty, you may have a mildew problem. Tiny fungi growing on the surface of the sheeting cause mildew. These fungi are always present in the air. The most common types are black, but some are red or green. The dirty area may be very localized. For example, it may be only under the eaves or on one side of your house. Or, it may cover an entire wall. If left untreated, the mildew may spread and darken, turning the affected area almost black. Mildew grows best in warm, humid conditions. There is no sure, long-lasting preventative for mildew since mildew spores are always in the air. Be sure to kill and remove mildew with a commercially available mildew remover before attempting to paint the surface. Allow the surface to dry thoroughly after using the mildew remover and then proceed with
How do I stop rust coming back on my railings?
Firstly use a wire brush and / or scraper to remove all dust, dirt and loose rust to ensure adequate adhesion. Sand or power tool clean the metal to a clear or by eye rust free surface. Prime all bare areas within 4 hours or before flash rusting occurs. For the best results use a Metal Primer specifically made to prevent rust, followed by one full oil based undercoat and two full top coats of premium acrylic or enamel. The important part is being sure to apply a full paint system. When sanding or power tool cleaning you leave a sharp edge between the bare metal and the still painted metal. This sharp edge must be sanded smooth to prevent lifting of subsequent paint layers at a later date. By applying two topcoats over a primer and an undercoat you will create a longer lasting finish before repainting will be necessary.
I have a painted block foundation: on the exterior I get white salt-like stuff on the surface that destroys the paint — what is this and how can I prevent it?
Efflorescence is often seen as a white fluffy deposit of salt crystals on cementitious wall surfaces. It depends on the presence of salt and moisture. The growth of crystals will continue as long as both are present. The salts are present in the mortar, blocks or concrete structure and the moisture source could be from a variety of locations. When emanating from mortar in brick or block substrates, efflorescence will start as narrow bands corresponding to mortar joints. Some of the causes of efflorescence include failure to adequately prepare the surface by removing all previous efflorescence, excess moisture escaping through the exterior masonry walls from the inside or insufficient curing time for new cement or mortar. If excess moisture is the cause, eliminate the source by repairing the roof, cleaning out gutters and downspouts, and sealing any cracks in the
Can I paint brick?
There are many different types of masonry materials used. Some can be very porous others may be slick and non-porous. Some can tend to be powdery or granular others solid. Because of these factors it is difficult to estimate the service life of a paint system over brick. If the surface is sound and porous the paint should acquire good adhesion and be capable of lasting as long as the actual label warranty of the product states,
Can I paint aluminium cladding? aluminium gutters?
Painting your old aluminium cladding and gutters makes good sense both economically and aesthetically. Not only can you make it look like new; you can change the colour and give it a whole new look. Surface preparation and the use of a top quality acrylic paints like Bristol Weather tough are the keys to painting aluminium cladding and gutters. First, any surface oxidation must be completely removed by careful, light rubbing with steel wool. If mildew is present, remove it by scrubbing with a bleach solution (one part bleach to three parts water). Power wash or hand scrub with warm soapy water and rinse. Be sure to remove all chalking, loose paint, dust, dirt, and bleach solution. Spot prime areas where bare aluminium may be exposed using All Surface Acrylic Primer.
Can I paint vinyl cladding?
Painting your old vinyl siding makes good sense both economically and aesthetically. Not only can you make it look like new; you can change the colour and give it a whole new look. Surface preparation and the use of a top quality acrylic paint are the keys to painting vinyl cladding. The first step is to remove any chalking and dirt by cleaning with a pressure washer or by hand scrubbing with warm soapy water and thoroughly rinsing.
NOTE: Never paint vinyl cladding with a colour darker than the original colour of the vinyl cladding. Dark colours absorb the sun’s heat which can cause the cladding to warp.
Can water damage to my stucco/vermiculite ceiling be repaired so that I won’t notice it?
A common problem with these coatings is that they can be water-soluble. Test a fast drying stain blocking primer, like stop tar primer, or if you have the time between coats a slow drying enamel primer works well. Once the stain problem is overcome than paint the entire ceiling with a premium acrylic paint like Easy-living flat or lo-sheen
I want to remove my stucco/ vermiculite from my ceilings, and then paint them — how do I do this?
The stucco/vermiculite material can be removed by scraping with a 6-inch stiff broad knife or with a wallpaper shaver. Scrape the ceiling down to a smooth surface. You will probably gouge the surface. To resurface the gouge apply a thin coat of joint compound over the entire area. Let the joint compound dry then sand smooth. After sanding remove any dust residue with a damp rag and allow to dry. The surface is now ready to be sealed with a coat of Acrylic Wall board sealer and then apply your desired finish coat of paint. Please note that this is a very time consuming task.
My deck keeps peeling year after year — what do I need to do to get something that lasts?
First we need to determine the reason for peeling. I suggest you call your local Sydney Painting Professional and have him perform a site inspection. The coatings that are on the surface should be removed. One probable cause of the peeling is the edge of the board facing the ground is not sealed allowing moisture to be drawn into it. The sun than hits the deck drawing the moisture through the board and the result is peeling paint or stain. Before coating the deck wash it. It is important that the surface is free of any wax or grease before sanding the surface, if not, the contaminates may be forced into the surface and cause future problems. Next sand the deck removing as much of the old coatings as possible. Remove the sanding dust and you are now ready to finish. The deck is now ready to be sealed and finished as per your choice of finish.
How long do I need to leave my pressure treated exterior wood before I can stain it?
Pressure treated wood contains a lot of moisture do to the chemicals being forced into the wood. The wood needs to be dry before staining. You can determine the porosity of the wood by dropping a few drops of water on it. If the water beads up wait, if it is absorbed into the wood it is ready to take stain. Typically, the amount of time you need to wait after the wood is installed is 2 to 4 weeks. If the water does bead wait a week
My pressure treated wood fence/deck has weathered to a darkish grey colour –what can I do to freshen it up?
This grey colour is the natural weathering process when bare wood is exposed to ultra violet rays. In order to freshen it up, clean the surface with an appropriate decking cleaner following the manufacturers instructions. This will restore the wood to its natural beauty. To keep the fence/deck looking good seal it and finish it with an appropriate water based wood finish.
My cedar wood fence/deck has weathered to a darkish grey colour — what can I do to freshen it up?
This grey colour is the natural weathering process when bare wood is exposed to ultraviolet rays. In order to freshen it up, clean the surface with an appropriate decking cleaner following the manufacturers instructions. This will restore the wood to its natural beauty. To keep the fence/deck looking good seal it and finish it with an appropriate water based wood finish.
When do I know that I have to repaint?
By looking at your house to determine if there are any areas where the paint is either chipping, peeling, cracking or otherwise just aging from weather. Some signs of natural deterioration is the thinning of the paint, this is caused by natures weathering. Colour change is also a common reason. This may be caused by a change in your surroundings, say a new roof.. It is important that your house maintains a good coat of paint on the surface to protect your investment. Do not fall into the trap of waiting until clear and visible signs of damage are present before deciding to act. This may be to late. All properties should be inspected on an on going basis and an appropriate maintenance program should be adhered to. Ask your local Sydney Painting Professional
What colours are hot now?
Colours are trendy and are always changing. We VERY strongly recommend the use of an appropriately trained colour consultant. Colour is an exact science and for the sake of a small price we can all avoid the disaster that occurs when we try and choose our own colours, and get it wrong.
I am getting water through my basement wall, I heard about a paint that can be used to stop this leaking — is there such a thing?
Yes these coatings are applied to the interior side of walls and will prevent the penetration of water from the other side. For these products to perform, the surface has to be clean of all surface contaminates including paint, efflorescence (a white salt deposit) and loose masonry. The efflorescence can be removed with a solution of 4 parts water to 1 part bleach using a good scrubbing brush, be careful to wear proper protective clothing and eyewear. And have plenty of ventilation. Next rinse the surface with clear water. Allow the surface to dry. Repair any loose masonry and allow to dry according to manufacturers directions. Seal with a block filler or appropriate acrylic sealer. Please note that as a result of this action the previous water traffic will be forced else where. Sometimes this may mean that the water pressure may build up and climb up the wall or travel sideways. It is therefore important to also tread the cause of the water problem as well
I just built a new house and want to keep the dust down in the garage — what can I put down on the floor?
New concrete that has been poured normally has a curing compound applied to it that must be removed. This can be done by using an acid Etch following the mixing instructions. Rinse and allow to dry. The newly prepare surface can then be sealed with standard paving style of paint or one of the many harder wearing products around. When a clear finish is required the above system can be followed and finishing can be done so with one of the many silicon or water based enamel products on the market.
I want to seal my patio bricks — what can I use?
To seal patio bricks they must be porous, clean and in sound condition. If you are looking for a clear sealer than there are many suitable products available that very in finish from dead flat to full gloss.
Still Have Questions?