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Installation Print

Installation

 The B.G.I. SMOOTHROCK VENETIAN PLASTER is 100% acrylic manufactured with the best resins, talcs, and clay available. Our plaster can be tinted to match any colour and due to the high solids content it is capable of opaque skimcoat coverage in a single pass.Smoothrock Venetian Plaster dries to a hard finish that can be polished to a high sheen during application or afterward using a polisher, pad and 320 grit sandpaper. This allows the applicator complete control during installation. Our Duragloss has been formulated to blend with our plaster for multi-coloured layering effects making it possible to push past the limits of the traditional lime and wax products. The installation techniques covered here are production techniques, meaning they are tried and tested over hundreds of thousands of square feet and have been proven to install quickly without compromise to beauty. In other words 1000 ft. sq. becomes 2000 ft. sq. in two passes instead of 5000 ft. sq in 5 passes cutting the installation time by over half, what that ultimately means to the applicator is the square foot price of a job has a greater degree of flexibility, but the end result looks as appealing as the more labor intensive system. Add the fact that polishing can be accomplished by machine instead of trowel, as well the possibility of installing large scale commissions is within the reach a single person or and any size crew.

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SKIMCOATING OF DECORATIVE PLASTERS;

It will become necessary in many applications to begin with a proper skimcoat of decorative plaster. A proper skimcoat creates a surface that is both smooth, and free from all deviations. To accomplish this the original surface must first be prepared as shown in step #1 below. Once the surface has been properly prepared skimcoating may begin. Apply the venetian plaster or BC-101/BC-105 on to the entire surface using a broadknife (see tools on products page) in large sweeping curves, the more random the skimcoat movemen tthe better. The skimcoat must be kept tight and smooth. Most surfaces will be adequately covered in two passes of skimcoat, however it may be necessary to apply a third if the surface does not appear smooth and free of imperfections after two skimcoats. It is possible with experience to render a surface completely smooth and free of imperfections in a single controlled skimcoat. However it is recommended to take the longer route until you become comfortable with the technique.

THE SKIP TROWEL FINISH:

         

THESE SAMPLES WERE CREATED USING SINGLE COLORS OF VENETIAN PLASTER IN SKIP TROWEL PATTERN

                    Step #1 start by preparing the surface to accept the treatment. With an existing surface it is usually possible to apply directly on to it. High gloss surfaces should be sanded with 120 grit paper before commencing  * remember to always check for wax or wallpaper glue residue before starting( these need to be dealt with before beginning. Remove sizing or residue with T.S.P.).  If the surface is new, eliminate any possibility of coating failure by priming the surface in an oil primer, B-I-N SHELLAC BASE is preferred. This will prevent any re-emulsification of the undercoat, which could result in cracking. If installation over existing papered surfaces is unavoidable then prime the surface in oil primer, B-I-N SHELLAC BASE is preferred, but remember to remove any paper that is peeling or can be removed without much effort (sand torn paper edges to minimize their visibility in the final finish) then sand the B-I-N after drying. with 120 grit sandpaper. Vinyl/paper should be fully removed in damp environments as it can trap moisture and rot the substrate( then remove sizing or residue with T.S.P.). Fill any severe imperfections with Versiplast (or equivelent) before beginning. Some fully settled surfaces will exhibit long cracks in varying widths ie/ older structures, these should be treated with a flexible latex, paintable caulking ( press deeply into crack then wipe smooth with a damp sponge) allow to dry 24 hours before priming or decorative plaster work).

            Step #2 The finish can begin one of two ways,skim first skip trowel second or skip trowel first skim second. Skip trowelling first is the quicker, more effecient method.If skip trowelling first is the chosen technique;

Begin by placing the venetian plaster across the long edge of the trowel (do not overload the trowel). There should be about 3/8 " of plaster across the blades full edge, now touch the trowel to the surface and move your hand in a random fashion ( the shape of an S works well) the pressure required to transfer plaster from the trowel to the surface is very minimal it is imperative that the thickness of the skip trowelled venetian be thick approximately 1/8" higher than the surface. this will allow the coating the opportunity to begin to set (dry) against the surface, but not at the high edge, this means that you can texture at least 40- 60 ft. sq. before coming back to the still wet skip trowelled areas, roughly 6- 10 minutes from the time you first skip trowel before coming back over these areas and laying a loose skim coat over top. This will fill in blank areas between skip trowelled areas as well as causing the still wet high areas to be carried along the surface with your skim coat. The skip trowel pattern will not be obliterated during this process because during the 6 - 10 minutes that it has sat on the surface an approximately 1/32" thickness of the skip trowel will have set up. It is important that the skip trowel step not be too thin as too much will dry in the 6 - 10 minute period, leaving too high of a relief pattern. This layer should be allowed to fully dry before finishing with the final coat. For the final pass scrape the surface  dry and skim a tight random coat of venetian plaster over top, depending on the speed of this final skim coat, you should only lay up between 10 - 30 sq. ft. then go back and begin trowel polishing the paster while it is wet enough to polish but set enough not to remove any product ( learning how to time this step is crucial to the overall appearance of the final work so experiment if you are a novice applicator) the stage between the wet and dry period is known as the flash. You must not miss the opportunity to polish during this stage, or you risk losing the polishing window and wont be able to bring up a luxurious high gloss 2 tone effect. That said you must return to all areas for a second polish, roughly 5 minutes after the first polish and polish with hard pressure, in a back and forth motion. This should complete your installation, you have the choice of leaving the surface this way or installing a protective clearcoat of DURAGLOSS also if a second colour of venetian plaster is desired then mix the venetian 50/50 with duragloss and pull across the surface in a random way. This will create a dramatic semi-trasparent layer that can be polished to a high sheen using the same method as described above for final pass polishing. Learning to work with multi-coloured layers of venetian plaster and duragloss  including trapping gelled (smoothrock pearls and metals) topcoats will elevate your skills and broaden the variety of choices to offer your clients.

Machine polishing: It may become necessary depending on the size of an area to be covered, time constraints, speed of installation limitations, or personal physical limitations to forego hand polishing for the much quicker and less labour intensive machine polishing technique. Smoothrock Venetian Plaster has been specially formulated to be hard enough to polish at high speed with 320 grit or finer sandpaper ( some applicators will take the machine polishing system from 320 grit then 600 grit and finish with a light spritzing of water with a final pass in 1000 grit wet/dry paper. This gives an indescribeable honed marble feel and a mirror gloss finish, however excellant results can be obtained with just one pass of 320 grit.* Softer lime based plasters must be tested before attempting this technique as they could sand away completely.

Machine method; Allow the venetian plaster to dry then using a commercial grade polisher( ie/ Makita 9227c or equivalent ) take a B.G.I. D500 8" Polishing pad and spray adhesive to the paper or pad then place the pad into the centre of the paper and use scissors or a razor knife to trim away excess paper from pad. Now place the pad onto the velcro head of the machine and you are now ready to begin polishing. Place the pad/paper onto the surface and turn the polisher on and dial the variable speed to desired r.p.m.( 5 is quick and effecient), avoid making contact with electrical outlet covers as they tend to tear the pad. The 320 grit paper should do the job for at least 200 ft. sq. then it should be replaced in the same fashion noted above. It is important to remember that sanding venetian gives a slightly different final appearance vs. hand polishing try both and decide which way you want to proceed.

The quick skip trowel techique above in combination with machine sanding is unbeatable for no nonsense rapid installation work. It is quite common for three applicators to work together with this system and complete 1800- 2300 ft.sq. per day. Depending on the price billed out per square foot this system can be extremely profitable.

THE CROSS HATCH FINISH: (TRADITIONAL)

        

THESE SAMPLES WERE CREATED USING SINGLE COLORS OF VENETIAN PLASTER IN CROSS HATCH PATTERN

  The cross hatch technique is the oldest known system for venetian plaster installation and is easily recognized by the small pattern of hits. The pattern is created by the type of trowel and the size of the strokes or as we say," HITS". It was considered to be the premium pattern of all hand applied plaster due in no small part to the fact that " the smaller the pattern" the more effort required, this translates into a labour intensive system that commands premium prices per square foot. Also when the cross hatch system is rendered in lime based venetian plaster, more coats are required to achieve a professional finish.

The trowels of choice were traditionally various sized stainless steel scrapers (from 1" to 4"). This finish is still available today but due to the amount of labour required be prepared to pay for it.

                  Step #1 start by preparing the surface to accept the treatment. With an existing surface it is usually possible to apply directly on to it. High gloss surfaces should be sanded with 120 grit paper before commencing  * remember to always check for wax or wallpaper glue residue before starting( these need to be dealt with before beginning remove sizing or residue with T.S.P.).  If the surface is new, eliminate any possibility of coating failure by priming the surface in an oil primer, B-I-N SHELLAC BASE is preferred. This will prevent any re-emulsification of the undercoat, that could result in cracking. If installation over existing papered surfaces is unavoidable then prime the surface in oil primer, B-I-N SHELLAC BASE is preferred, but remember to remove any paper that is peeling or can be removed without much effort (sand torn paper edges to minimize their visibility in the final finish) then sand the B-I-N after drying. with 120 grit sandpaper. Vinyl/paper should be fully removed in damp environments as it can trap moisture and rot the substrate( then remove sizing or residue with T.S.P.). Fill any severe imperfections with Versiplast (or equivelent) before beginning. Some fully settled surfaces will exhibit long cracks in varying widths ie/ older structures, these should be treated with a flexible latex, paintable caulking ( press deeply into crack then wipe smooth with a damp sponge) allow to dry 24 hours before priming or Venetian work).

 To achieve this finish with SMOOTHROCK VENETIAN PLASTER you must first fully skimcoat the surface with your venetian until all imperfections are obliterated and the surface is smooth to the touch. Try to keep the skimcoat random and sand the final skimcoat with 220 grit sandpaper. Now you may begin the pattern.

 Step #2 start by placing a hit of venetian plaster on the wall in the size appropriate to your final finish. Use stainless steel scrapers in chosen width. Now place a hit beside the first and allow it to slightly overlap the first hit. The hits should be thin and tight (this will cause quick drying to occur). The quicker drying time of this system means you will constantly be polishing before the joints go cold. It is important to remember that overlapping single hits are not enough to develop an acceptable finish, you must cause a multi-layering of hits to get an acceptable appearance. That said, there is a much easier way to obtain the cross hatch finish using a much less traditional approach ; 

THE CROSS HATCH FINISH: (NON-TRADITIONAL)

Fully skimcoat the surface with your venetian until all imperfections are obliterated and the surface is smooth to the touch. Try to keep the skimcoat random and sand the final skimcoat with 220 grit sandpaper. Now you may begin the pattern, start by placing a multiple hits across the entire surface, keeping the hits apart from one another by just less than the width of a hit. When you have finished the first full pass your surface should resemble the pattern of a girraffe's hide. Simply return to the place you began at and repeat the procedure but this time this second layer of hits sould preferrably make contact with two edges from your first layer. This layer will begin to" close the surface", roughly four times around the surface should fully close the pattern. Now the pattern is in place and you have several choices,

  1. Machine method; Allow the venetian plaster to dry then using a commercial grade polisher( ie/ Makita 9227c or equivalent ) take a B.G.I. D500 8" Polishing pad and spray adhesive to the paper or pad then place the pad into the centre of the paper and use scissors or a razor knife to trim away excess paper from pad. Now place the pad onto the velcro head of the machine and you are now ready to begin polishing. Place the pad/paper onto the surface and turn the polisher on and dial the variable speed to desired r.p.m.( 5 is quick and effecient), avoid making contact with electrical outlet covers as they tend to tear the pad. The 320 grit paper should do the job for at least 200 ft. sq. then it should be replaced in the same fashion noted above. It is important to remember that sanding venetian gives a slightly different final appearance vs. hand polishing try both and decide which way you want to proceed. Machine sanding/polishing removes the need for timely and fatiguing hand polishing and increases the rate of installation by tenfold. Smoothrock Venetian Plaster has been specially formulated to be hard enough to polish at high speed with 320 grit or finer sandpaper ( some applicators will take the machine polishing system from 320 grit then 600 grit and finish with a light spritzing of water with a final pass in 1000 grit wet/dry paper. This gives an indescribeable honed marble feel and a mirror gloss finish,however excellant results can be obtained with just one pass of 320 grit.* Softer lime based plasters must be tested before attempting this technique as they could sand away completely.

  2. Apply a finish coat of venetian and duragloss 50/50 (see duragloss options in duragloss page). This coat can be installed rapidly and will give protection and contrast. Remember that to increase the amount of contrast in the final effect you should alter the 50/50 mixture with white tint to suit.ie/ more white tint means more contrast.You can polish this finish by hand or machine. Follow the machine method above if a machine finish is required. If a final coat of duragloss is needed, install according to instructions shown in duragloss page and polish with the D-500 pad only.

Regardless of the choice of techniques, your finish will be perfect if you follow these guidlines.

THE KNOCKDOWN / HAMMERED FINISH:

         

THESE SAMPLES WERE CREATED USING MULTIPLE COLORS OF VENETIAN PLASTER IN KNOCK DOWN PATTERN

      Step #1 start by preparing the surface to accept the treatment. With an existing surface it is usually possible to apply directly on to it. High gloss surfaces should be sanded with 120 grit paper before commencing  * remember to always check for wax or wallpaper glue residue before starting( these need to be dealt with before beginning remove sizing or residue with T.S.P.).  If the surface is new, eliminate any possibility of coating failure by priming the surface in an oil primer, B-I-N SHELLAC BASE is preferred. This will prevent any re-emulsification of the undercoat, that could result in cracking. If installation over existing papered surfaces is unavoidable then prime the surface in oil primer, B-I-N SHELLAC BASE is preferred, but remember to remove any paper that is peeling or can be removed without much effort (sand torn paper edges to minimize their visibility in the final finish) then sand the B-I-N after drying. with 120 grit sandpaper. Vinyl/paper should be fully removed in damp environments as it can trap moisture and rot the substrate( then remove sizing or residue with T.S.P.). Fill any severe imperfections with Versiplast (or equivelent) before beginning. Some fully settled surfaces will exhibit long cracks in varying widths ie/ older structures, these should be treated with a flexible latex, paintable caulking ( press deeply into crack then wipe smooth with a damp sponge) allow to dry 24 hours before priming or Venetian work).

Step #2 Using the venetian plaster begin by skimcoating the entire surface area. A proper skimcoat should cover all deviations and imperfections and look and feel smooth to the touch. When the skimcoat has dried, place a fair quantity of venetian plaster into a paint tray (approximately 2 quarts). Keep a wet rag over the product to ensure that it does not dry in the tray. You can thin the venetian with duragloss or water to make rolling easier. Now charge the sea sponge roller (as seen on products page"tools") with venetian plasterand roll onto surface in an even pattern. To achieve an even pattern you must learn how much pressure to use when releasing the plaster onto the surface. Try to have a light hand when initially making contact with the surface and allow the pressure to increase as plaster discharges onto surface. It is recommended that your roll stroke take on a random x type motion, as this allows for more control, recharge the roller  before plaster runs out on the sponge. It is vitally important that you begin to knock back the plaster before it has time to begin setting up. A good rule is to roll out approximately 4-5 ft. sq. then knock it back, then continue the process. The knockdown procedure is best performed with a broadknife (see tools on products page) and the stroke that works best is again an x type movement. You should see the plaster spread from many small dots into a larger, flatter pattern. Dont be too concerned about missing areas as you can go back across the surface a second time and fill in undesirable patches. It is actually reccommended that you make a full second pass with the sea sponge roller technique to achieve a consistant knockdown pattern. The danger in allowing the plaster to sit on the surface too long before knocking it down is that the plaster will sit up too high on the surface creating an unwanted relief.

Step #3  Machine polish using the guidlines above. If more dimension is required trowel polish the first pass of venetian plaster and machine polish the final pass of venetian plaster.

Optional Step #4 Granite Technique, Various colors of venetian plaster can be sea sponge rolled simultaneously for simulating granite effects, as well small quantities of metallic topcoat can be sea sponge rolled onto the surface to achieve a more realistic quatrz particle that naturally occurs in real granite.                    (see above samples) It is recommended that applicators experiment fully with several techniques, products, and colors to gain a better understanding of the flexibility of the B.G.I. line of coatings.

THE POLISHED STONE FINISH:

       

THESE SAMPLES WERE CREATED USING MULTIPLE AND SINGLE COLORS OF VENETIAN PLASTER

THIS FINISH UTILIZES THE SA-650 AGGREGATE BASECOAT WITH THE ST-500 SMOOTHROCK VENETIAN PLASTER

The polished stone finish is based on a traditional lime based procedure but has been converted into an all acrylic system. The undercoat layer is a thinly trowelled veneer of our SA-650 aggregate basecoat which contains a fine silica sand particle in a durable acrylic plaster. The finish coat is our SMOOTHROCK venetian plaster trowelled over the dry SA-650 aggregate basecoat.It is then polished to reveal the pattern created by the undercoat.

      Step #1 start by preparing the surface to accept the treatment. With an existing surface it is usually possible to apply directly on to it. High gloss surfaces should be sanded with 120 grit paper before commencing  * remember to always check for wax or wallpaper glue residue before starting( these need to be dealt with before beginning remove sizing or residue with T.S.P.).  If the surface is new, eliminate any possibility of coating failure by priming the surface in an oil primer, B-I-N SHELLAC BASE is preferred. This will prevent any re-emulsification of the undercoat, that could result in cracking. If installation over existing papered surfaces is unavoidable then prime the surface in oil primer, B-I-N SHELLAC BASE is preferred, but remember to remove any paper that is peeling or can be removed without much effort (sand torn paper edges to minimize their visibility in the final finish) then sand the B-I-N after drying. with 120 grit sandpaper. Vinyl/paper should be fully removed in damp environments as it can trap moisture and rot the substrate( then remove sizing or residue with T.S.P.). Fill any severe imperfections with Versiplast (or equivelent) before beginning. Some fully settled surfaces will exhibit long cracks in varying widths ie/ older structures, these should be treated with a flexible latex, paintable caulking ( press deeply into crack then wipe smooth with a damp sponge) allow to dry 24 hours before priming or Venetian work).

Step #2 Using the  SA-650 aggregate basecoat trowel a thin layer across the entire surface, the edge can be kept open on larger surfaces to avoid a cold joint by lightly spritzing the open edgw with water. Trowel this coat no thicker than the height of the silica sand found in the SA-650. You can also lightly spritz the SA-650 during installation and float the product in a circular motion to create even more patterning. Scratch lines are to be expected in this stage and make up a portion of the final effect. Once the entire surface area has been rendered allow it to fully dry,then scrape away all nibs from the surface. NOTE: Using a pool trowel and a plasterers hawk is the fastest way of applying this coat.

Step #3 Begin by trowelling the ST-500 Smoothrock venetian plaster in a random stroke pattern over the        SA-650 aggregate basecoat, keep the venetian tight to the surface. After the entire surface has been covered allow it to dry.

Step#4 Now the final pass of  ST-500 Smoothrock venetian plaster can begin. Installing this final layer also requires that you go back as the venetian begins to dry and trowel polish the plaster. The polishing will highlight both the aggregate undercoat and the venetian strokes that you have made.

Step#5 (optional) Clearcoat the finish with Duragloss for protection (follow guidelines in Duragloss page).With the polished stone system two coats of duragloss are recommended.

Feel free to experiment with the venetian plaster ie: 50/50 venetian to duragloss in second color value, as seen in first sample above. NOTE: LIGHTER COLORS OF VENETIAN PLASTER WILL REVEAL THE AGGREGATE UNDERCOAT AS A BLACK MOLECULE. This can be effective in rendering a more stone like finish, hence Polished Stone finish. Also the  SA-650 aggregate basecoat can be tinted and then taped off in a block pattern using our blocking tape, and then the tapes can be pulled after all the venetian overcoating work has been completed. This will create an effective stone pattern with contrasting grout coloring.