Roof coatings and roof membranes with Desmodur®/Desmophen® polyurethane systems – a durable solution for a long roof life

Polyurethane roof coatings based on Desmodur® / Desmophen® are a very reliable solutions for new roofs as well as for renovation projects. They can be applied as a seamless and root-proof film and prevent water leakage even with complex roof structures. Also, they are resistant against fire sparks and heat radiation. More requirements can be looked up in the national and european regulations. Please refer to the European Organisation for Technical Approvals (EOTA)

Polyurethane roof coatings are applied in a liquid state. They cure to form a permanently elastic weather-resistant membrane. When formulated with Desmodur® and Desmophen® raw materials, these coatings help to preserve the appearance of the coated roof for many years, and ensure that the surfaces remain sealed. Above all, their highly elastic character - even at very low temperatures - prevents the ingress of water into the structure. Upstands, built-in windows and drainages remain tightly bound into the waterproofing membrane.

These systems are available as one-component systems for manual application or as fast curing two-component systems for spraying equipment. Typical methods for primer application are brushing, rolling or spraying.

Typical build-up of a roof coating

Watch this video (4:30 min appr.) to find out more about processing and application of polyurethane roof coatings

Raw material suggestions for roofing membranes:

	Type	Solids in %	% NCO or OH on solids	Viscosity mPas at 23°C	Characteristics
Desmodur® E 15	TDI prepolymer	100	4.4 NCO	7000	For thick film and very elastic one- and two-component coatings, e.g. for crack bridging on concrete surfaces and for coating flat roofs
Desmodur® N 3600	HDI trimer	100	23.0 NCO	1200	For lightfast two component polyurethane coatings with high resistance to chemicals and weathering, outstanding mechanical properties
Desmodur® XP 2406	IPDI prepolymer	80	3.5 NCO	7000	For large surfaces with good storage stability and good flexible properties also at low temperatures
Desmodur® Z 4470 BA	IPDI trimer	70	17.0 NCO	600	For lightfast two-component polyurethane coatings with high resistance to chemical and weathering, very good gloss retention and outstanding mechanical properties
Desmodur® VL 50	MDI polyisocyanate	100	32.5 NCO	22.5 (25 °)	For highly flexible coatings with low viscosity during mixing
Desmophen® 1150	Polyester polyether polyol	100	4.7 OH	3500	In combination with e.g. Desmodur® VL 50, for tough and flexible coatings, hard-wearing and chemicalresistant; in combination with Desmodur® L high resistance sealing compounds
Desmophen® VP LS 2249/1	Polyester polyol	100	15.5 OH	1900	Used in formulations of hard and weatherstable coatings, sealing compounds
Hardener® VP LS 2959	Urethane bisoxazolidine	100	330.0 NH-equivalent	3000	Hardener for one-component polyurethane systems

An example of a suitable starting formulation:

RR 5323	Two-component polyurethane membrane, very elastic, crack bridging (Desmodur® E 15)

Contact our experts for more starting formulations for roof coatings.