Applications

EXISTING ROOF – Thermal Insulation without slopes with DESMOFLEX PU System

Applications

EXISTING ROOF – Thermal Insulation without slopes with DESMOFLEX PU System

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Floors Repair Waterproofing Repairing Plasters

What do we need?

Brush, roller, paintbrush, airless spray, trowel

STEP 1 Surface Cleaning: Clean the surface thoroughly to remove oils, loose materials, dust, etc. Where protrusions are present (e.g. tie wires), they should be cut to a depth of approximately 3 cm. Thoroughly wet the surface until saturated and then repair the relevant areas using REPIFIX REPAIR WRM 519.

STEP 2 Epoxy Primer: Apply the two-component, water-based epoxy primer DESMOFLEX EPOXY PRIMER using a roller, brush or paintbrush, after mixing the two components according to the manufacturer's instructions. The product penetrates deeply and provides excellent adhesion to both absorbent and non-absorbent substrates. It can also be applied to damp concrete surfaces and is an ideal primer before the application of polyurethane waterproofing membranes. The next layer should be applied after 6–12 hours, while the surface remains slightly tacky, in order to achieve optimum adhesion between the layers.

STEP 3 Waterproofing: Apply the two-component polyurethane-bitumen waterproofing membrane D-FLEX® BITU for the waterproofing and protection of horizontal and vertical surfaces against moisture and water. The material is applied by roller, brush, notched trowel or mechanical spray in two successive coats, creating a continuous, elastic and seamless waterproofing membrane. It can be applied in high thicknesses and effectively bridges cracks. It is suitable for roof waterproofing, as well as for application underneath thermal insulation boards or tiles. D-FLEX® BITU is characterized by fast curing, high elasticity, excellent mechanical properties and resistance to seawater and most chemicals, providing long-term and reliable waterproofing protection.

STEP 4 Installation of Thermal Insulation Boards: Install the 10 cm ULTRAPOR XPS thermal insulation boards. The boards are installed as the thermal insulation layer of the system, providing high thermal protection. Thanks to their low thermal conductivity and extremely low water absorption, they ensure stable and long-term performance.

STEP 5 Floor Screed: Apply NSD 600 floor screed for floor filling, levelling and smoothing. The material can be applied mechanically using a continuous mixing machine or manually. It is evenly spread at a thickness of 8 cm, creating a strong and stable surface with high mechanical strength and strong adhesion to concrete. It is suitable for preparing floors prior to the installation of tiles, marble, parquet and other final floor finishes. NSD 600 offers excellent workability, can be applied on sloped surfaces and provides high compressive and flexural strength, ensuring a stable and reliable substrate.

STEP 6 Reinforcement Mesh: Install T131 structural reinforcement mesh, ensuring adequate overlap between sheets and securing them with binding wire. The mesh should be placed on suitable spacers so that it is positioned within the upper third of the screed thickness and is completely covered by the screed.

STEP 7 Expansion and Contraction Joints: Joints are incorporated into the screed to control shrinkage and expansion and prevent cracking. Perimeter joints are formed around walls and vertical elements using expanded polystyrene, while internal contraction joints are formed every 2.5–3 m or approximately every 10–15 m². The joints are formed during the hardening process or by cutting after the material has set. They are subsequently sealed using a polyethylene backer rod and elastic polyurethane sealant ELASTO PU. At perimeter joints, the expanded polystyrene remains in place and, where required, sealant is applied to the surface.

STEP 8 Surface Priming: Apply the two-component, water-based epoxy primer DESMOFLEX EPOXY PRIMER using a roller, brush or paintbrush, after mixing the two components according to the manufacturer's instructions. The product penetrates deeply and provides excellent adhesion to both absorbent and non-absorbent substrates. It can also be applied to damp concrete surfaces and is an ideal primer before the application of polyurethane waterproofing membranes. The next layer should be applied after 6–12 hours, while the surface remains slightly tacky, in order to achieve optimum adhesion between the layers.

STEP 9 First Coat – DESMOFLEX POLYURETHANE: Apply the first coat of DESMOFLEX POLYURETHANE, a ready-to-use solvent-based polyurethane waterproofing membrane, using a roller, brush or suitable spray equipment, creating a uniform elastic waterproofing layer at a consumption of approximately 0.5–0.8 kg/m² per coat. The membrane offers excellent elasticity and cures through moisture from the air and substrate, creating a continuous, seamless and hydrophobic surface. It is capable of bridging cracks up to 2 mm. While DESMOFLEX POLYURETHANE is still wet, install the THRAKON waterproofing tape (KF 12/7 or F 12/7) at corners, floor-to-wall junctions and connections with parapets, in order to ensure the bridging of critical points and the watertightness of the system.

STEP 10 Second Coat – Embedding of THRAKON FABRIC: While the first coat is still wet, install the THRAKON FABRIC polyester reinforcement fabric, ensuring that it is fully embedded into the material, without folds or air pockets. Apply a second coat of DESMOFLEX POLYURETHANE, undiluted and crosswise to the first coat, at a consumption of approximately 0.4–0.5 kg/m², ensuring complete coverage of the fabric and creating a continuous, elastic waterproofing membrane.

STEP 11 Final Protective Coating: Apply the final protective two-component polyurethane coating DESMOFLEX TOP COAT after completion of the DESMOFLEX POLYURETHANE waterproofing system. Apply by roller or suitable spray equipment (airless spray), in one or two coats, at a consumption of approximately 120–250 g/m² per coat. The coating creates a smooth, glossy and stable high-whiteness finish, protecting the polyurethane membrane against ultraviolet radiation, natural chalking and weathering. It provides excellent adhesion, high abrasion resistance and high resistance to weather conditions and standing water, ensuring long-term protection.

Products Used