Polyurethane Molding Installation Guide: A Step-by-Step Manual from Layout to Final Brushstroke

Molding can transform a space over a weekend—if you know how to install it. Polyurethane decor forgives beginners' mistakes, requires no special equipment, and weighs dozens of times less than its plaster counterpart. But between 'gluing it somehow' and 'professional installation' lies a chasm. The former creates crooked joints, gaps, and peeling elements. The latter delivers perfect lines, seamless connections, and decades of flawless appearance.installation guide for polyurethane molding—this is not a list of general tips but a sequence of specific actions that lead to results. From wall preparation to final painting, from interior cornices to facade elements.

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Surface Preparation: Where Quality Begins

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Substrate Requirements for Interior Molding

A wall or ceiling is the foundation on which the decor rests. A poor substrate guarantees problems — peeling elements, uneven lines, visible gaps between the molding and the surface. What should the ideal base be like?

Flatness is a critical parameter. Allowable deviations should not exceed 3-5 mm over a 2-meter length. A cornice or molding installed on a wavy wall will follow all the curves and look like a snake. Flatness can be checked with a long straightedge (2-2.5 meters) placed against the wall. Gaps larger than 5 mm between the straightedge and the wall are a signal that leveling is needed. Plastering, puttying, sanding — which method to choose depends on the magnitude of the deviations. Deviations of 10-20 mm are eliminated with plaster on beacons, 3-10 mm — with finishing putty in several layers.

Substrate strength determines the reliability of the fastening. Loose, crumbling plaster will not hold the molding — the adhesive will bond with the weak layer, which itself will fall off in a month or two. The test is simple: run a hard object (coin, key) over the wall with pressure. If deep scratches remain, the plaster crumbles — reinforcement is needed. A deep-penetration primer with a strengthening effect (e.g., acrylic-based) is applied in 2-3 coats with intermediate drying. It impregnates the surface layer to a depth of 5-10 mm, polymerizes it, and creates a strong structure.

Cleanliness — the absence of dust, dirt, grease stains, wallpaper residue, paint. Dust prevents contact between the adhesive and the substrate, grease repels water-based adhesives. The wall must be cleaned — sweep off dust with a brush, wipe with a damp cloth, and let dry. Grease stains (especially in the kitchen) are removed with a degreaser or soapy solution followed by rinsing with clean water.

Substrate dryness is a mandatory condition. Wall moisture should not exceed 4-5% for concrete and plaster, 10-12% for drywall. Fresh plaster dries for 3-4 weeks, drywall after puttying — 7-10 days. Installing molding on a damp substrate will lead to mold under the elements, adhesive failure, and deformations. Signs of excessive moisture — dark spots, a surface that feels cold to the touch, condensation. If in doubt, measure the moisture with a non-contact moisture meter.

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Primer: Why It's Needed and How to Apply It Correctly

Primer is not a decorative but a technical layer that performs three functions: strengthens the surface, improves adhesion (adhesive bonding), and evens out absorbency. Skipping the primer is a common mistake that reduces installation quality.

The type of primer depends on the substrate. For mineral surfaces (concrete, plaster, brick, aerated concrete), an acrylic deep-penetration primer is used. It penetrates pores to a depth of 5-10 mm, polymerizes the surface layer, and reduces water absorption. For drywall, a universal acrylic primer is suitable — it is less porous, so deep penetration is not required. For painted surfaces (if installing molding over old paint), a concrete-contact primer with quartz filler is needed, which creates a rough surface for better adhesive bonding.

Primer is applied with a short-nap roller or a brush (e.g., a paint pad). A roller is for large areas (walls, ceilings), a brush for hard-to-reach places (corners, behind pipes). The primer is applied evenly, without gaps or puddles. One coat dries in 2-4 hours at a temperature of +20°C and 50-60% humidity. Usually one coat is sufficient, but highly absorbent surfaces (aerated concrete, old plaster) require two coats with intermediate drying.

Full polymerization of the primer occurs within 24 hours. Molding can be installed one day after priming. Rushing — installation 2-3 hours after priming — reduces adhesive adhesion by 30-40% because the primer has not fully hardened yet.

Features of Facade Preparation

Installing polyurethane molding on a facaderequires more rigorous substrate preparation — the facade is exposed to precipitation, temperature fluctuations, ultraviolet light, and mechanical impacts. The substrate must not only be flat and strong but also protected from moisture.

Facade plaster is the optimal base. Cement-sand plaster with a thickness of 20-30 mm creates a strong, moisture-resistant layer. It must be completely dry — at least 28 days for full cement hydration. Wet facade plaster under molding is a source of mold, efflorescence, and peeling.

A painted facade is a complex case. If the paint is firmly adhered (test: stick tape to the facade, rip it off sharply — if the paint does not peel, it is strong), installation is possible. But the surface must be treated with a concrete-contact primer to create roughness. If the paint is peeling, it must be completely removed mechanically (with a scraper, brush, sandblasting) down to the substrate.

An insulated facade (ETICS — External Thermal Insulation Composite System) requires a special approach. Molding is installed not on polystyrene or mineral wool, but on an reinforcing layer of fiberglass mesh and adhesive compound. This layer must be at least 5-6 mm thick, completely dry (7-14 days), and protected with finishing plaster. Installation on a weak reinforcing layer will cause the molding to tear off along with the mesh.

Tools and Materials: The Arsenal for Perfect Installation

Tools for Cutting and Fitting

Miter box — a device for cutting at an angle. A simple plastic or wooden miter box with slots for 45° and 90° costs 300-500 rubles, suitable for cornices and moldings up to 100-120 mm wide. A professional metal miter box with a swivel mechanism allows setting any angle with an accuracy of 1°, working with elements up to 200 mm wide, and costs 3000-8000 rubles.

Miter saw — a power tool for fast and precise angled cutting. Blade diameter 210-255 mm, power 1200-1800 W, ability to adjust cutting angle from 0° to 45-50° left and right. The cut is perfectly smooth, without chips, takes 5-10 seconds. For a one-time repair, buying a miter saw is excessive (cost 8000-25000 rubles), but renting for a day costs 500-1000 rubles.

Handsaw — a manual tool for cutting molding. A handsaw with fine teeth (pitch 1.0-1.5 mm) — for wood or metal — is needed. Coarse teeth tear polyurethane, leaving ragged edges. A blade length of 30-40 cm is optimal for cornices 80-150 mm wide. Cutting with a handsaw requires care — saw without pressure, evenly, holding the saw strictly horizontally.

Utility knife — for trimming small elements, beveling edges, cleaning up uneven cuts. The blade must be sharp — a dull blade tears rather than cuts. Change the blade every 5-7 cuts for a clean result.

Sandpaper with grit P120-P180 for sanding cut ends. Even a cut with a sharp handsaw leaves small burrs that interfere with a tight joint. 2-3 strokes with sandpaper along the end remove burrs and make the edge smooth.

Tools for Applying Adhesive and Installation

Caulking gun for 310 ml adhesive and sealant cartridges. A skeleton gun (metal frame, rod, lever) costs 200-400 rubles and suits most tasks. A professional cordless gun with an electric drive dispenses adhesive evenly, without effort, costs 3000-8000 rubles — justified for large volumes.

Putty knives of several sizes: narrow 40-60 mm for working in corners and small details, medium 100-120 mm for filling joints, wide 200-250 mm for applying putty to large areas. Metal knives with a flexible blade give smooth surfaces. A rubber knife for filling joints on relief elements — it is flexible, fills unevenness without damaging the ornament.

Spirit level 60-100 cm long for controlling the horizontality of cornices and moldings. A laser level simplifies marking — projects a horizontal or vertical line onto the wall, and you align elements along it. Cost of a simple laser level 1500-3000 rubles, rental 300-500 rubles per day.

Tape measure 5-7 meters long, pencil for marking, square for checking right angles, painter's tape for fixing elements while the adhesive sets.

Materials: Adhesives, Sealants, Putties

Adhesive for polyurethane molding — a specialized compound that ensures strong adhesion to mineral substrates. Types of adhesives:

• Acrylic mounting adhesive (acrylic-based liquid nails) — a universal option for interiors. 310 ml cartridge, setting time 10-30 minutes, full polymerization 24 hours. Suitable for elements weighing up to 3-5 kg per linear meter. Solvent-free, safe, odorless. Examples: Tytan Classic Fix, Момент Монтаж Суперсильный, Soudal Fix All.

• Polyurethane adhesive foam — a one-component compound that expands during polymerization, filling substrate irregularities. Adhesion is very strong, holds heavy elements (rosettes 100+ cm in diameter, wide relief cornices). Expansion 10-20%, excess must be trimmed after curing. Setting time 30-60 minutes, full polymerization 24 hours. Examples: Ceresit CT 84, Soudal Purocol.

• Adhesive filler — a thick acrylic compound that both adheres and fills irregularities. Applied with a notched trowel to the back of the element in a 3-5 mm layer. Suitable for walls with variations up to 5-7 mm — the adhesive filler compensates for unevenness. Setting time 20-40 minutes. Example: Orac Decofix Pro.

Adhesive consumption: for a 2-meter cornice strip 80-100 mm wide, 50-80 ml of adhesive is used. A 310 ml cartridge is enough for 4-5 strips, i.e., 8-10 meters of cornice.

Acrylic sealant for sealing joints, gaps between molding and wall/ceiling, minor defects. Essential properties: paintable (so it can be painted to match the elements after drying), elastic (to prevent cracking from micro-movements). Color — white if the molding remains white, or paintable if it will be painted. Cartridge 280-310 ml, consumption approximately 1 cartridge per 10-15 meters of joints. Examples: Ceresit CS 25, Soudal Acryl, Tytan Professional.

Acrylic finishing filler for sealing large joints, leveling surfaces before painting. Ready-made filler in 1-3 kg buckets is more convenient than dry — no mixing required, consistency is stable. Filler should be white, fine-grained (filler fraction up to 0.1 mm), easy to sand after drying. Examples: Knauf Rotband Finish, Ceresit CT 127, Sheetrock.

Installation of cornices and moldings: step-by-step technology

Marking: where precision begins

Ceiling cornice is mounted along the perimeter of the room at the wall-ceiling junction. First — determine the lower edge of the cornice, draw a horizontal line on the wall around the entire perimeter. Distance from the ceiling depends on cornice width: for an 80 mm wide cornice, offset 80 mm from the ceiling; for 100 mm — 100 mm, i.e., equal to the width.

Marking starts from one corner. Measure down from the ceiling a distance equal to the cornice width, mark. Repeat in another corner of the same wall. Connect the marks with a straight line using a 1-2 meter spirit level or laser level. Laser is easier — set it up, project a horizontal line, trace with a pencil. A standard bubble level requires patience — place it, level by bubble, draw a line along the level, reposition.

Repeat marking on all walls. Result: a straight horizontal line should run around the room perimeter at an equal distance from the ceiling. This is the baseline along which the cornice's lower edge is aligned.

Cutting corners: the main challenge for beginners

Room corners are rarely exactly 90°. Old houses, new building settlement yield angles of 88-92°. Cutting cornice at standard 45° for such corners guarantees gaps. What to do?

Measure the angle with a construction protractor or angle finder. Place the protractor in the corner, lock, read. A 90° angle is halved — each of the two converging cornices is cut at 45°. Angle 88° — each cornice at 44°. Angle 92° — each at 46°. If no protractor, use the two-strip method: place two cornice strips in the corner as they should stand after installation, mark lines on the back of each strip along the other strip's end. These lines indicate the cut direction.

Cutting in a miter box for standard 90° angles. Place cornice in the miter box in the same position as on the wall — e.g., for ceiling cornice: top edge (toward ceiling) pressed to miter box bottom, bottom edge (toward wall) pressed to miter box side. Cut with a saw through the miter box slot at 45° in the required direction (left or right, depends on whether it's the left or right corner of the cornice).

Cutting with a miter saw for any angles. Set the saw to the required angle (e.g., 44° for an 88° room angle), place cornice on the saw table in working position, make the cut. Miter saw gives a perfect cut in 5 seconds.

Adjusting the cut with P120-P180 sandpaper. Even a precise cut may have micro-irregularities. 2-3 sanding strokes along the end make it smooth, joint tight.

Applying Adhesive and Installation

Adhesive is applied to the back of the cornice — on the two planes (shelves) that will contact the wall and ceiling. For acrylic adhesive (liquid nails), optimal application is zigzag or dotted line with 5-10 cm spacing. Do not apply a continuous thick layer — excess will squeeze out, stain the wall, require lengthy cleaning. A thin zigzag provides sufficient adhesion with minimal consumption.

For polyurethane adhesive foam, apply a thin continuous line along each shelf. Remember, foam expands 10-20%, don't overdo it. Better to add later than clean excess.

Element is placed against the wall so the lower edge aligns with the marked line. Press along the entire length evenly, with force, for 20-30 seconds for initial adhesive setting. Acrylic adhesive sets quickly; after 10-20 minutes, the element holds on its own. Polyurethane foam requires 30-60 minutes and fixation during that time.

Fixation during setting time is needed for heavy or long elements that may detach under their own weight. Options:

• Painter's tape, applied every 50-70 cm from cornice to ceiling or wall. Holds element pressed while adhesive cures. Tape removed after 2-4 hours.

• Decorative nails (finishing nails with small heads) driven into the lower part of the cornice contacting the wall, spaced 60-80 cm apart. After adhesive cures, nails are removed, holes filled. Or left in place if heads are countersunk and filled — provide additional hold.

• Props — vertical battens or blocks, one end on the floor, the other against the cornice, holding it pressed to the wall. Relevant for heavy ceiling cornices with lighting.

Joining strips: how to avoid visible seams

On a 4-meter wall, two 2-meter strips need joining. The joint is made in the middle of the wall, not in the corner. Ends of both strips are cut at a right angle (90°), joined butt-to-butt.

Invisible joint technique:

• Ends of both strips after cutting are sanded with sandpaper — perfectly even, no burrs.

• A thin layer of adhesive (acrylic or special polyurethane joint adhesive) is applied to one of the ends.

• The planks are pressed together with force so that the adhesive is squeezed out as a micro-layer. The pressure is maintained for 30-60 seconds.

• After the adhesive has cured (24 hours), the joint is practically invisible. If a thin gap of 0.3-0.5 mm remains, it is filled with acrylic sealant using a rubber spatula.

Mistakes that make the joint visible:

• No adhesive on the ends — the joint remains open, a gap is visible.

• The ends are uneven, do not fit tightly — a gap of up to 1-2 mm, which has to be filled with putty. After painting, such a joint stands out.

• Mismatch of profiles — if the planks are slightly rotated relative to each other, the pattern does not match, the joint is visible even in the absence of a gap. It is necessary to ensure that both planks are positioned identically relative to the marked line.

Installation of ceiling rosettes: perfect framing for a chandelier

Preparing the rosette and ceiling

Polyurethane ceiling molding for a chandelier— a rosette is an element mounted on the ceiling around the light fixture mounting point. The first step is to ensure the wiring is routed through the center of the rosette.

Rosettes usually have a pre-made central hole with a diameter of 60-100 mm for passing wires. If the hole is insufficient or absent, cut it out with a utility knife. The hole diameter should be 10-20 mm larger than the diameter of the chandelier's mounting cup so it can pass through freely.

The ceiling at the installation site must be level, clean, and primed. The hook or mounting bracket for the chandelier should already be installed, and the wires routed. The length of the hook is important — it should protrude beyond the thickness of the rosette by 20-30 mm so that the chandelier's mounting cup presses tightly against the rosette.

Marking the center and applying adhesive

The center of the rosette must coincide with the point where the wires exit. How to find the exact center on the ceiling? If the wires exit through a hole, that is the center. If the wires do not exit exactly where the rosette center is planned, they need to be relocated (by turning off the electricity, extending the wires, and routing them through a new hole).

Make a temporary center mark with a pencil. Place the rosette against the ceiling with its center aligned to the mark, and trace its outline with a pencil. This will help during installation — it shows where to place it.

Adhesive is applied to the back of the rosette along the perimeter and in a cross pattern through the center. For rosettes with a diameter of 60-80 cm, acrylic adhesive-putty applied with a notched trowel in a 3-5 mm layer is suitable. For rosettes 100+ cm, it is better to use polyurethane foam adhesive — it is stronger and compensates for ceiling irregularities.

Installation and Fixation

The chandelier wires are threaded through the central hole of the rosette. The rosette is placed against the ceiling, its center aligned with the mark, and its outline aligned with the traced line. Press the rosette evenly against the ceiling with your hands across the entire area. A heavy rosette is difficult to hold in place for 5-10 minutes until the adhesive sets.

Methods for securing a heavy rosette:

• A long wooden slat or block, braced with one end on the floor and the other against the center of the rosette, presses it against the ceiling. Attach a soft pad (foam, cloth) to the top end of the slat to avoid damaging the rosette's relief. The slat remains in place for 4-6 hours until the adhesive sets.

• Screws through the rosette into the ceiling at 4-6 points around the circumference, 10-15 cm from the edge. Screws 40-50 mm long are driven with a screwdriver into pre-drilled holes in the ceiling (6 mm diameter, 40 mm deep, with plastic plugs inserted). The screw heads are countersunk into the rosette by 2-3 mm and filled with putty after the adhesive cures. This method provides maximum reliability for rosettes with a diameter of 100-140 cm.

Excess adhesive squeezed out along the edges of the rosette is immediately removed with a damp cloth or spatula. Do not wait for it to cure — cured polyurethane adhesive can only be removed mechanically, damaging the rosette.

Facade installation: when decoration goes outside

Specifics of facade adhesive

The facade is exposed to precipitation, frost, ultraviolet light, and wind loads. Interior adhesives do not work here — they lose strength when frozen and cannot withstand moisture. Special facade adhesives on a mineral or polymer base are required.

Adhesives for facade molding:

• Ceresit CT 85 — a polymer-cement mixture for reinforcing facade insulation systems. High adhesion to mineral substrates, frost resistance, moisture resistance. The mixture is diluted with water to a thick consistency, applied with a notched trowel to the back of the element in a 5-8 mm layer. Open time 20-30 minutes, full curing 72 hours.

• Ceresit CT 84 — polyurethane foam adhesive for facade expanded polystyrene. 850 ml cartridge, applied with a mounting gun. Minimal expansion (5-10%), setting time 30-60 minutes. Suitable for small and medium-sized polystyrene and polyurethane molding (cornices, moldings, small overlays).

• Foam adhesive for extruded polystyrene (e.g., Soudal Soudabond Easy, Tytan Styro 753) — a one-component polyurethane adhesive that does not contain solvents that can dissolve polystyrene. Suitable for facade elements weighing up to 5 kg per m².

Facade adhesive consumption is higher than interior adhesive — the layer is thicker (5-8 mm vs. 2-3 mm) because facade walls are usually less even.

Mechanical fastening: when adhesive is not enough

Large facade elements (cornices 200+ mm wide, large overlays 50×50 cm or larger, columns, pilasters) require additional mechanical fastening with dowels. The adhesive bears the main load, while dowels provide backup against detachment under wind loads.

Combined fastening technology:

1. The element is test-fitted to the facade, and drilling points are marked. For a 2-meter-long element, 4-6 fastening points are sufficient (every 40-50 cm).

2. Holes are drilled with a hammer drill through the element into the wall. Diameter 8-10 mm, depth 60-80 mm. Use a concrete drill bit if the base is brick or concrete.

3. Plastic facade dowels 80-100 mm long with wide caps (insulation mushroom dowels) are inserted into the holes.

4. Adhesive is applied to the back of the element with a notched trowel in a 5-8 mm layer.

5. The element is placed against the facade, aligned with the holes. Screws are driven into the dowels or expansion nails are hammered in. The caps are countersunk into the element by 2-3 mm.

6. After the adhesive cures (72 hours), the caps are filled with facade putty and sanded with sandpaper.

Moisture protection: hydrophobization and painting

Polyurethane does not absorb water (water absorption less than 1% in 24 hours), but joints between elements and dowel fastening points are vulnerable spots. Water that gets into a joint freezes in winter, expands, and damages the connection. Protection is critical.

Sealing joints with facade acrylic or polyurethane sealant. Joints are filled with sealant using a caulking gun and smoothed with a rubber spatula. The sealant must be elastic, frost-resistant, and paintable. Examples: Soudal Silirub 2, Ceresit CS 25.

Hydrophobization — treating the molding surface with a hydrophobic agent that makes it water-repellent. The hydrophobizer is applied with a brush or sprayer in 1-2 coats after installation and joint sealing. Water rolls off the surface, does not absorb, and does not freeze. The effect lasts 3-5 years, after which reapplication is needed.

Painting with facade paint — final protection. Acrylic, silicone, or silicate facade paint creates a dense coating that protects the molding from UV rays, precipitation, and dirt. Paint is applied in 2 coats with intermediate drying of 4-6 hours. Paint consumption for molding is higher than for smooth walls (due to relief) — consider a coefficient of 1.3-1.5.

Final finishing: from rough to perfect

Filling joints and gaps

Even perfectly cut and installed elements have micro-joints — gaps of 0.3-1.0 mm, visible upon close inspection. The goal of final finishing is to make joints absolutely invisible.

Sealing is performed no earlier than 24 hours after installation. The adhesive must be fully cured, and elements must be firmly secured. Premature sealing — the adhesive is still mobile, the element may shift slightly, and the sealing material will crack.

Material for sealing: acrylic sealant or acrylic finishing putty. Sealant is more elastic, does not crack with micro-movements, ideal for joints. Putty provides a smoother surface, is easier to sand, and suitable for larger irregularities.

Technique for sealing joints:

1. The joint is cleaned of dust and adhesive residue with a dry brush.

2. A small amount of sealant is squeezed into the joint using a caulking gun. The tube nozzle is cut at a 45° angle, hole diameter 3-5 mm — so the sealant comes out in a thin strip.

3. A rubber spatula or damp finger is run along the joint, pressing in the sealant and smoothing the surface. Excess is removed, making the joint flush with the elements.

4. For relief elements (cornices with complex profiles), use a thin tool (toothpick, stylus) to restore the ornament lines at the joint. Sealant fills the gap but should not cover relief details.

Sealing gaps between molding and wall/ceiling — same technique. The gap is filled with sealant and smoothed with a spatula. If the gap is wider than 3-5 mm (wall uneven, element not fitting tightly), first fill it with acrylic putty, let dry, sand, then apply sealant for final leveling.

Sanding: preparation for painting

Sanding is needed if irregularities are visible on sealed joints, putty, or if fingerprints remain on the sealant. Sand with fine sandpaper P180-P240 using light strokes. Goal: smooth out irregularities without damaging the molding relief.

Sanding creates fine dust. After sanding, remove dust with a dry brush or vacuum. Dust on the surface interferes with paint adhesion and causes uneven coverage.

Painting: color and finish

Polyurethane molding is supplied white (base polymer color — milky white or pure white). Many leave it white, but if another color is needed, the molding is painted.

Priming before painting — a debated point. Polyurethane has low absorbency, and acrylic paint adheres well without primer. But if the molding has a glossy factory surface, primer improves paint adhesion. Use acrylic primer for non-absorbent surfaces, apply a thin coat with a brush or roller, let dry 2-4 hours.

Paint: water-based acrylic or latex. Oil-based paints, solvent-based enamels must not be used — solvents (white spirit, acetone, solvent) dissolve polyurethane and polystyrene. Acrylic paint is safe, odorless, dries quickly (2-4 hours), and provides a durable coating.

Finish selection:

• Matte paint provides a soft, velvety finish without reflections. Suitable for classic interiors where molding serves as a delicate background, not an accent. Hides minor surface imperfections.

• Satin (semi-matte) — a light silky sheen that accentuates relief without making the molding glossy. A compromise between matte and glossy. The most versatile.

• Glossy paint creates a shiny finish that highlights every detail of the relief, providing interplay of light and shadow. Suitable for accent molding that should stand out. Reveals any imperfections — unevenness, scratches, putty marks.

Painting technique:

The first coat is applied with a brush for detailed painting of the relief. Use a medium-sized brush (40-60 mm wide) with resilient synthetic bristles. The paint should not be thick — dilute with water by 5-10% if needed. Paint without pressure, in a thin layer, covering all recesses and protrusions. The first coat dries in 2-4 hours.

The second coat is applied after the first is completely dry. You can use a short-nap roller (for smooth elements) or a brush again (for relief elements). The second coat evens out the color, eliminates gaps, and creates the final finish. If a saturated color is needed (dark shades — gray, blue, black), apply a third coat.

Patination and gilding — decorative techniques for creating an aged or luxurious effect. Base coat — white or light paint in 2 coats. After drying, apply gold, silver, or bronze paint with a sponge or fine brush to the protruding parts of the relief. Or patina (dark paint diluted with glaze) is rubbed into the recesses to create contrast. These techniques require care; it's better to practice on a scrap piece of molding.

Cost of work: doing it yourself or hiring professionals

Price of professional installation

polyurethane molding installation work pricedepends on complexity, region, order volume. Rates in Moscow and major cities (February 2026):

• Installation of ceiling cornices — 250-400 rubles per linear meter. Price depends on the width and relief of the cornice. Simple smooth cornice 250-300 rub/m, complex relief cornice 350-400 rub/m.

• Installation of wall moldings — 200-350 rubles per linear meter. Narrow moldings (up to 50 mm) — 200-250 rub/m, wide (80-150 mm) — 300-350 rub/m.

• Installation of a ceiling medallion — 1500-4000 rubles per piece depending on diameter. Medallion 60-80 cm — 1500-2500 rub, medallion 100-120 cm — 3000-4000 rub.

• Installation of decorative overlays — 150-300 rubles per piece depending on size.

• Sealing joints, sanding — 80-150 rubles per linear meter of joints.

• Painting molding — 150-250 rubles per linear meter for cornices and moldings, 500-1500 rubles for a ceiling medallion.

Total: installation of cornices around the perimeter of a 5×6 meter room (22 linear meters) with painting will cost 22 × (300 + 150) = 9900 rubles. Plus a ceiling medallion 80 cm in diameter: installation 2000 rub + painting 1000 rub = 3000 rub. Total about 13000 rubles for labor. Materials (cornices, medallion, adhesive, paint) — another approximately 15000-20000 rubles. Total costs 28000-33000 rubles.

Savings with DIY installation

If you do it yourself, you only pay for materials — 15000-20000 rubles. Savings of 13000 rubles on labor. But you need to spend time: installation of cornices and a medallion will take 1-2 full days (preparation, marking, cutting, installation, joint sealing) plus another day for painting (two coats with intermediate drying). Total 2-3 days of work.

If you're not confident in your skills, you risk doing worse than a pro — crooked joints, visible gaps, peeling elements. Redoing it will cost more than hiring a specialist initially. Assess your readiness for manual work, attention to detail, and availability of tools.

A compromise — do some of the work yourself (surface preparation, priming, painting), and entrust installation to professionals. This reduces labor costs by 30-40%, while preserving the quality of complex operations (angle cutting, installation).

Frequently asked questions

Can molding be installed on wallpaper?

No, wallpaper is an unreliable base. The adhesive will bond to the wallpaper, but the wallpaper itself may peel off the wall under the weight of the molding. Result — molding falling off along with pieces of wallpaper. Remove wallpaper in installation areas, adhere molding to the wall or plaster. Or install molding before wallpapering, trimming the wallpaper to the edge of the molding.

What is the best adhesive for polyurethane molding?

For interiors — acrylic liquid nails (Tytan, Moment) or special adhesive-putty (Orac Decofix Pro). For heavy elements — polyurethane adhesive foam (Ceresit CT 84). For facades — facade mineral adhesive (Ceresit CT 85) or facade polyurethane adhesive (Soudal, Tytan Styro). Do not use adhesives with solvents — they dissolve polyurethane.

Is primer needed before installation?

Yes, primer improves adhesive adhesion to the base by 40-60%, strengthens the surface layer of plaster, and evens out absorbency. Without primer, the adhesive may bond weakly, especially on loose, dusty, highly absorbent surfaces. One coat of acrylic deep-penetration primer is sufficient.

How soon can molding be painted after installation?

No sooner than 48 hours. The adhesive must fully cure. If painted earlier, the adhesive still releases moisture, which can cause the paint to blister or dry poorly. Joints sealed with caulk or putty must also dry — typically 24-48 hours. Total: wait at least two days from installation to painting.

How to cut polyurethane cornice without chipping?

Use a fine-tooth saw (pitch 1.0-1.5 mm) or a miter saw with a blade for wood or aluminum (80-100 teeth). Cut without strong pressure, smoothly, holding the saw strictly horizontal or at the miter box angle. Fast cutting with pressure causes chipping. After cutting, always sand the cut end with sandpaper P120-P180 — this removes tiny burrs.

Does facade molding withstand frost and rain?

Yes, polyurethane is frost-resistant (withstands from -50°C to +80°C), moisture-resistant (water absorption less than 1% in 24 hours), does not rot, and is not damaged by ultraviolet light (if painted). Correct installation is critical — use facade adhesive, mechanical fastening with dowels, seal all joints, and paint with facade paint. Then the molding will last 20-30+ years without deterioration.

Can a rosette be installed on a stretch ceiling?

Yes, but the technology is more complex. First, a ceiling rosette is mounted to the base ceiling using adhesive and dowels. Then, a stretch ceiling fabric is installed with a cutout for the rosette. The fabric is glued to the rosette with special adhesive. Alternatively, the rosette can be mounted on top of the stretch ceiling if it is lightweight (up to 60 cm in diameter, weighing up to 1 kg), using adhesive without dowels. For heavy rosettes, this installation method is unreliable — the rosette may fall off, tearing the fabric.

What is the difference between polyurethane molding and polystyrene molding?

Polyurethane is stronger (does not break upon impact), denser (250-350 kg/m³ compared to 25-40 kg/m³ for standard polystyrene), moisture-resistant (polystyrene is also moisture-resistant), but 30-50% more expensive. Polystyrene is lighter, cheaper, and sufficiently durable for most applications. For interiors, the difference is minimal; both are suitable. For facades, polyurethane is preferable due to its greater strength and impact resistance.

How to care for molding after installation?

Molding does not require special care. Dust is removed with a dry soft brush or a vacuum cleaner with a brush attachment every 2-3 months. Grease stains (in the kitchen) are wiped with a damp cloth and mild detergent, then with clean water. Do not use abrasive cleaners or stiff brushes — they scratch the surface. Painted molding lasts 7-10 years, after which you can repaint it.

How much does it cost?Buy polyurethane molding for walls?

Prices (February 2026): cornices 150-600 rub/m depending on width and relief, moldings 100-400 rub/m, rosettes 800-5000 rub/piece depending on diameter (60 cm — 800-1500 rub, 80 cm — 1500-2500 rub, 100 cm — 2500-4000 rub, 120-140 cm — 4000-6000 rub), decorative overlays 50-500 rub/piece. A full set for a 20-30 m² room (cornices, moldings, a rosette) — 15,000-30,000 rubles.

Conclusion: installing molding is an accessible skill

Installing decorative elements made of polyurethanedoes not require years of experience. Basic repair skills, care, correct materials, and following instructions are enough for a result you won't be ashamed to show. Polyurethane forgives minor mistakes — it can be trimmed, sanded, and filled. It is lightweight, does not require heavy-duty fastening, and adheres with standard compounds.

Key success factors: thorough surface preparation (levelness, strength, priming), precise corner cutting (measuring with a protractor, using a miter box or miter saw, cleaning the ends), correct adhesive choice (acrylic for interiors, facade for outdoors, polyurethane for heavy elements), quality joint sealing (sealant, filler, sanding), final painting (acrylic paint, two coats, detailed painting of the relief).

Facade installation is more complex than interior installation — it requires special adhesives, mechanical fastening with dowels, thorough sealing, and protective painting. But the technology is the same — marking, cutting, installation, sealing, painting. The main thing is to account for external factors (moisture, frost, ultraviolet) and use materials that withstand them.

DIY installation saves 40-60% of the budget compared to hiring professionals. For a 20-30 m² room, the savings amount to 10,000-15,000 rubles. This justifies the time (2-3 days of work) and effort. If you are unsure of your skills, start with something simple — install a baseboard or a narrow molding on a short wall. Practice, assess the difficulty, and decide — continue on your own or hire a specialist.

STAVROS offers a full range of polyurethane and polystyrene molding for interiors and facades.Ceiling corniceswith widths from 40 to 250 mm, over 50 profiles with varying degrees of relief.wall moldingswith widths from 20 to 200 mm for creating panels, frames, horizontal and vertical accents.light fixtureswith diameters from 30 to 140 cm in classic and modern styles. Decorative overlays, pilasters, brackets, corner elements for complete interior decoration.

High material quality is guaranteed by working with trusted manufacturers. HI WOOD (South Korea) polystyrene elements have a density of 680 kg/m³ — 13-20 times denser than standard polystyrene, providing strength comparable to polyurethane at the price of polystyrene. Polyurethane elements from European manufacturers ensure moisture resistance, impact resistance, and durability of 20-30 years.

STAVROS consultants will help you select elements for your project, calculate the required quantity, and recommend suitable adhesives, sealants, and paints. We will explain installation nuances, provide instructions, and answer questions. For those who decide to install themselves, this is valuable support that increases the chances of success.

Warehouse programs in Moscow and St. Petersburg ensure availability of main items, quick shipment on the day of order or the next day. Delivery in Moscow and Moscow Region — 1-2 days, in St. Petersburg — 2-3 days, to regions via transport companies — 4-14 days depending on distance.

Create beauty with your own hands, saving your budget and enjoying the process, with quality materials and professional support from STAVROS — your partner in decorating interiors and facades.