I’m seeking help from experts regarding the calculation of heat loss in greenhouses and pipelines

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At the precast site for T-beams on the construction site, insulation is required during winter construction; a simple heating shelter needs to be built so that the ambient temperature of the concrete beams can reach around 20 degrees Celsius. The warm greenhouse is 110 meters long in length, 2 meters high, and 1.6 meters wide; it is intended to maintain a temperature of 20 degrees. The greenhouse is covered with 4 cm thick rock wool insulation for fire protection, and its floor is made of concrete. The external temperature is assumed to be 0 degrees. A 24KW electric wall-mounted boiler is connected to two 32mm diameter (with a wall thickness of 3mm) steel pipes arranged vertically – one for hot water outlet and the other for cold water return – for heating purposes. The temperature of the hot water outlet is 70 degrees, while the temperature of the cold water return is assumed to be 50 degrees; a sufficient circulation pump should allow the temperature of the cold water return to be increased. 1. What is the heat loss per square meter for a heated greenhouse? 2. What is the heat dissipation per meter of heating pipe (on average, including 2 pipes for water inlet and outlet)? Is it sufficient to cover the heat loss of the supplementary greenhouse? Is it necessary to add fins to the steel pipe? 3. Does the 24KW wall-mounted boiler meet the heating requirements? According to the formula in the engineering case manual for heat loss: Heat loss = Cross-sectional area * Temperature difference / (0.114 + Insulation thickness / Thermal conductivity + 0.04), I calculated the heat loss as 97 W/meter using the formula 5.6 * (60 – 20) / (0.114 + 0.04/0.04 + 0.04). Is it correct to use a thermal conductivity value of 0.04 for rock wool? If there are any experts out there, I would be very grateful if they could help me answer these 3 questions. Especially for question 2, it would be great if a detailed calculation process could be provided. Thank you very much.