Cement Render - always requires a good sanding down before applying a sealer. 120 grade paper is recommended for this purpose. You can use a heavier sandpaper but for interiors we recommend 120 grade paper as it will not scratch the surface and damage the finish. There are several sealers available on the market. "Acrylic Sealer Undercoat" is the most common with "Bondcrete" coming up next. "Wallboard sealer will suffice but most professionals prefer to use "Acrylic Sealer Undercoat" or "Ultraprep" which is made by Taubmans Paint. Any gaps can be filled with an acrylic gap filler like Selleys "No more gaps". There are plenty of equivalent products available on the market. These are available at any hardware or paint shop. Gyprock - All gyprock or plasterboard should be sanded and dusted. Then a sealer should be applied. The sealer specifically designed for these surfaces is called "Wallboard Sealer". It is made by all paint manufacturers and readily available at all good paint stores. This sealer is water-based and can be tinted to match you topcoats for easy coverage. Lead - Lead Removal is a hazard and should you have lead paints in your house they should be eradicated so that you and your family will not risk lead poisoning. The best product on the market is Peelaway. It is clean and it can remove lead and multiple layers of paint clean and hassle free. Removes up to 30 layers in one application. Peel away, it's new, it's different and it works, with the ability to remove multiple layers of paint in one application with no dust or fumes. The process allows complete containment of any lead based paints for safe disposal, preserves the substrate, is less labour intensive and eliminates harmful solvents. When using Peelaway always follow the instructions that come with the product. Hint: When applying the "peelaway" wrap make sure that you remove all bubbles from the surface that you are stripping as it works best when there is no air bubles on the surface. Also I like to put "bluetack" on the edges brickwork and other unpainted surfaces to really hold the plastic wrap in place. Lime & Sand Finish - When you are repairing old houses and units this type of surface often falls away and the more that you scrape the more that falls away. I have found that it is good to stop where it stops without scraping too much. Then apply 1 coat of diluted "Bondcrete" mixed 3:1 and seal the surface before patching it with ready mixed plaster. It is recommended that this surface be lightly sanded before a sealer is applied. The best sandpaper is 120 grade paper and it really only requires a very light rub over. "Acrylic Sealer Undercoat" is the best product for this surface. "Ultra prep is also a very good product for this surface. Plaster - Patching plaster is easy when you have scrapes but when you have big holes with cavities behind them it becomes a bit more difficult. To patch a hole such as this one you will need to follow some simple steps. Apply some stud adhesive to the exposed timber beam. Screw a piece of gyprock, (Plasterboard) that has been cut to size over the hole. Plaster set around the edges with some plaster basecoat. Finally sand the base coat and apply 1 or 2 coats of ready mixed plaster. These products are available at all good hardware and painting trade stores. Acrylic - "Acrylic Sealer Undercoat" once again is best for sealing timber that is intended to be painted with acrylic paints. (water based gloss and semi gloss also low-sheen paint). The timber should be sanded first and the the "Acrylic Sealer Undercoat" can be applied. Then no matter which sheen level of acrylic paint you have chose simply sand with 120 grade sandpaper between each coat. Usually after the sealer is applied only two coats of top coat are necessary. Nail holes should be filled with an acrylic based putty. Enamel - "Sanding Sealer" is once again recommended. First step is to sand the timber with 180 grade sandpaper. Second step is to apply an undiluted coat of "Sanding sealer" and allow to dry for 24 hours. Step three is to sand the sealed timber again. As you sand it it will turn white. Step four is to wipe it down with a damp cloth and from there you are ready to apply a coat of oil based under coat. It is recommended that you tint your under coat to a similar colour as your intended top coat colour, lightly sanding between coats. Nail holes should be filled with a linseed oil putty. Gaps between woodwork and the walls should be gap filled with an acrylic gap filler like Selleys "No more gaps". There are plenty of equivalent products available on the market. Varnished Surfaces - There is a product on the market made by "Dulux" and "Solver" paints. It may also be available from some other manufacturers. It is called "Sanding Sealer". This sealer is absolutely fantastic for sealing timber to be stained of lacquered. First step is to sand the timber with 180 grade sandpaper. Second step is to apply an undiluted coat of "Sanding sealer" and allow to dry for 24 hours. Step three is to sand the sealed timber again. As you sand it it will turn white. Step four is to wipe it down with a damp cloth and from there you are ready to apply a clear coat of "Polyurethane" in any sheen level that you desire or apply a coat of "Stain". If you are staining then you will find that the stain goes on much more evenly. Or you can apply "Wattyl One Step" which is a stain and gloss or semi-gloss finish in one. It comes in many timber colour varieties and is very easy to apply especially after using the sanding sealer. Nail holes should be filled after sealer is applied so that the putty does not enter the grain. There is a huge range of coloured putties on the market to choose from. The best product on the market for exterior natural timber finishes is called "Intergrain". It is a simple and easy process to coat up your timber and what is even better is that it is water based. The first step to to apply their revivor which really cleans the timber beautifully and prepares the surface for the sealer. The next step is to apply the sealer, (Brush only) and then the third step is to apply two coats of the "DWD" topcoat, (Brush only). It comes in a large variety of natural timber colours and can be purchased in low sheen and gloss finishes. It is available at "Bunnings Warehouses" and "Crockers hardwares". It has a potential of 5 years before recoating which is impressive for an exterior timber finish. Villaboard & Fibro - Although wallboard sealer is adequate for these surfaces most trade professionals also believe that "Bondcrete" is an acceptable sealer especially if you are going to tile that area. It is recommended that the "Bondcrete" product be mixed 3 parts to 1 with water. It is best to apply it with a brush as it is very watery and runs quite easily. However with a brush it spreads very well and darkens the surface as it is applied. Once finished the surface is truly sealed and great for surface preparation where the paint work meets an area that is going to be tiled. This product cannot be tinted but comes with anti-mould as a standard feature. You can also use "Bondcryl" for the same purpose.