Exterior Panels and Specialty Mural Surfaces

Exterior Murals, Instruments, Portraits and Animals

Rule for using this skill: These notes add specialist tips to your answer. They do not replace it. Always give your full general answer first, drawing on everything you already know. Then work in the tips below wherever they apply. Do not drop general advice because it is missing here, and do not limit the answer to what is listed.

Exterior mural: ventilated panel system

• Use thin, tough cement panels cut to size and shape on site. Pre-install them in the final configuration before any painting.
• Panels isolate the mural substrate from the existing wall, and air flowing behind them prevents moisture and condensation build-up.
• Panels let the mural be painted in the studio, away from weather and onlookers. They can also be removed later for conservation.
• Cement panels crack if handled wrongly. Ship each one in its own wooden "cradle" of 2' × 4' (61 × 122 cm) timbers, with 2' × 3' (61 × 91 cm) pieces under the length of the panel.
• If installation is in the artist's contract, supervise it and understand every aspect. Use a fully licensed, insured, experienced contractor.

Exterior mural: hat channels, flashing, gusset

• Heavy-duty galvanized steel hat channels attach the panels to the wall. They can stay on the wall through the whole painting period (nine months in the case study).
• Flashing is custom-fabricated stainless steel that keeps water off the back of the mural. Design and paint it in advance so it blends into the design.
• Cut a slot with a grinder directly into the brick facing. Mortar the flashing into it with waterproof mortar so it becomes a permanent part of the wall.
• The flashing face hangs down over the upper panel edge as a rain shield.
• Leave an air gap between the flashing and the top panel edges, and another at the bottom of the panels. Air then passes freely behind the mural, giving water and condensation an evaporation escape path.
• After the flashing is in, make final adjustments to the hat channels. Add short channels between the primary supports for extra impact resistance.
• Gusset: stick EPT-type rubber strips with double-sided tape to the front of the hat channels. The panels and screws hold them permanently.
• The strips isolate the panels from the channels. This avoids condensation where sun-warmed panels touch the metal behind the surface.

Exterior mural: installing panels

• Slip the panels under the flashing, then reposition carefully and check level and plumb.
• Fasten through the face with stainless steel screws. Some panel systems allow blind fastening so no fasteners show.

Exterior mural: paint and protection

• Paint system, in order:
  1. Alkaline-resistant primer.
  2. Lightfast, exterior-rated Golden acrylic paint.
  3. Isolation coat of soft gel gloss acrylic varnish.
  4. Two coats of MSA varnish.
• MSA varnish is a sacrificial clearcoat against UV and graffiti. Solvents can remove it even years later, taking dirt or spray paint with it. Then reapply it to return the mural to like-new condition.
• For community engagement, set up an information station with an FAQ brochure and a guest book.

Painted instrument: crackle gesso ground

• Crackle gesso recipe: mix albumin powder with cold water, about 9 oz (250 g) albumin to 2.5 cups (600 ml) water, to make the glue base.
• Add whiting until the mix is thick and soupy. Brush it onto untreated wood.
• It dries with a delicate crackle. Sand it, then basecoat with Bone White (or Off White) casein paint.

Painted instrument: design and transfer

• Work the design out on tracing paper with a soft pencil. Once it is final, go over it in permanent marker.
• Tracing paper lets you judge how the elements work together and flip symmetrical elements from one side to the other. Adjust size, proportion and line flow at this stage.
• To transfer, rub charcoal sparingly on the back of the tracing paper, or use graphite paper. Trace through from the front with a stylus.

Painted instrument: casein painting

• Use ready-made casein colors with synthetic bristle artist's brushes.
• Basecoats: pastel colors dulled with a little black or brown, applied as flat, opaque coverage.
• Shadows: washes of a darker color over the base in shadow areas. Water the casein down until slightly transparent. Pick one light source and follow chiaroscuro.
• Decorative brushstrokes add the darkest accents and some highlights, following the flow of the curves.
• Hold the brush perpendicular to the surface. Support the brush hand with your free hand to get more distance from the surface.
• Casein suits flowing strokes because it is opaque and does not dry quickly on the palette or in the brush. It also wears back well.

Painted instrument: aging and patina

• Wear back: rewet the painted surface with strong tea (a pot made with three or four tea bags). Wet casein wears back easily with a small sponge or scrubbing pad.
• Make small dents by hitting the surface with a chain.
• Antiquing wax: paste wax + turpentine at 1:2, colored with earth pigments (raw umber, burnt umber, raw sienna). Blend well.
• A wax combining beeswax and carnauba is good. Apply the wax after the surface has dried.
• Optionally apply a thin coat of shellac (traditional amber) or varnish before waxing, as extra protection.
• Let the wax dry, then buff with a wool rag and rottenstone. Repeat the wax step to build up the patina.

Faux fresco portrait: surface and transfer

• Stretch Fredrix Polyflax/Polymural canvas tightly, with no wrinkles or creases.
• Apply a thin layer of PlasterTex (Faux Effects) with a 4-inch (10 cm) or 9½-inch (24 cm) tapered stainless-steel plaster trowel. Cover the canvas weave completely, then let it dry.
• Project the original with an Artograph MC-250 projector. Use a high-resolution copy sized to fit the glass projection panel.
• Scale the client's face print to the original foreground figure's face. Resize it in photo-editing software if needed, then trim it.
• Tape the print down with 1-inch (25 mm) masking tape and transfer with Saral Wax-Free transfer paper (graphite). Trace the geometry and shadow reference lines, checking as you go.

Faux fresco portrait: glazing sequence

• Work like a watercolorist, light to dark. Render details first (face, hands, basic background lines), then apply translucent glazes over them.
• Initial lines: no. 2 round, Faux Effects AquaColors Red Oxide thinned with water so it flows.
• Block in fabric folds and architecture with thinned Red Oxide. Use "Big Space, Big Brush; Little Space, Little Brush": no. 2 round for small areas, no. 4 or 8 round for larger ones.
• To remove hard edges, reduce the paint with a wad of cheesecloth. Start with firm pressure and gradually lighten it so the edge fades as a gradient.
• Add Dark Brown to the Red Oxide to deepen the fabric values (deepest tones sit near the folds) and the shadows on both faces and necks.
• Wash thinned Dark Brown over the background architecture and the background sleeve. Let it set 1–2 minutes, then reduce with cheesecloth. Paint the boats with a no. 1 or 2 round.
• Cloak and sleeve wash: Red Oxide + Dark Brown (2:1) with a little water over the whole fabric. Let it dry.
• Background rooftops, mountains, sky and water: Ultramarine Blue + Dark Brown thinned with water. Use more water and less color for sky and water, and less water and more color for rooftops and mountains.
• Punch up the architectural details and the darkest fold shadows with Dark Brown + VanDyke Brown on a no. 12 or ¾-inch (19 mm) Golden Taklon flat. Block in the foreground fabric with Earth Green.
• Shrubs and trees: Ultramarine Blue + Dark Brown, then let dry.

Faux fresco portrait: highlights, distressing, gold

• Everything up to this point is transparent wash. Now add opaque highlights for punch and to clean up shapes.
• Mix a drop or two of Red Oxide into opaque acrylic white (Faux Effects Super Crème White) to warm the highlights. Apply with a round brush to the headdresses, background architecture and hair braids.
• Highlights on shrubs and trees: a drop or two of Dark Brown in the white.
• Distress: gently sand the whole canvas with 220-grit paper, with light pressure near the faces.
• Then wash on Dark Brown + water (1:10) with a 2-inch (51 mm) chip brush.
• Immediately mist the wet wash with a fine spray of Activator II (reactive solvent) from a spray bottle. It reacts with the glazes and opens them up into "watermarks" that look aged.
• Blot excess Activator II with cheesecloth, especially around the faces. Let dry.
• Final highlights: Eggplant + white on the background figure's torso and sleeve, and Red Oxide + white on the foreground fabric.
• Paint the delicate sleeve decoration with Master Dutch Metal Gold (Faux Effects) on a no. 1 or 2 round.

Animal mural: projector transfer

• Overhead projector: trace the image onto a transparency with a fine-point felt-tip marker. Include strong shadows and highlights, skip small details, and capture the basic shape of the lights and darks.
• Opaque projector: no transparency is needed, but still make a drawing with the same information. It needs a dark room but allows more detail.
• Overhead projectors work in lit areas, but small details are easily lost.
• Project the image, move it until you and the client approve the position, then trace it onto the wall in chalk.
• Use chalk close to the color of the finished painting. It mixes into the paint and can stay visible if you are careless.
• Before moving the projector, unplug it (do not just switch it off) and turn the room lights on to check the whole image has transferred. Unplugging avoids nudging the projector, which would distort the proportions.

Animal mural: fur, shadows, highlights

• Choose two or three dominant colors (e.g. Faux Effects AquaColors Autumn Brown and Dark Brown). With a medium square brush, paint a loose, washy value-study underpainting.
• Stroke in the direction of the fur rather than "coloring in". Leave the facial features for later and let it dry.
• Shadows: avoid black. Use Dark Brown + Eggplant with a little Autumn Brown, and a tiny amount of Black only in the darkest darks. Keep strokes in the fur direction and let dry.
• Go really dark. An all-midtone mural looks flat.
• Highlights: Autumn Brown + Ochre Yellow + a very small amount of White. Too much white goes chalky.
• Use midtones to blend out highlight edges. In thick fur, use definite strokes with little blending.
• Mix small batches of color on the palette so the mural doesn't repeat the same six or seven colors.

Animal mural: features and finishing

• Rough in the features with a smaller square or round brush. Show shape with darks and lights rather than blocking in flat color.
• Eyes, nose and mouth: Black, White, Dark Brown. Tongue: French Red, White, Violet.
• Build up the shadows and highlights of the features by thinking in shapes of dark and light, not "eye" or "nose". Paint what you see, not what you know.
• Edges: features can look as if they "jump" off the fur. Soften selected harsh edges with the feature brush, blending the two adjoining colors (Black for the nose, Autumn Brown for the fur).
• Add any extra shadows cast around the features. With experience, do this wet-into-wet while painting the features.
• Brightest highlights: White + Ochre Yellow with a very small round brush. On the wet areas (eyes, nose, tongue) these make them read as wet.