Why are exposed water pipes lagged with straw in winter?

Exposed water pipes are lagged with straw in winter to provide insulation and prevent freezing. Straw is an effective insulator due to its air-filled structure, which helps to maintain the temperature of the water inside the pipes. By reducing heat loss, lagging with straw helps to ensure that the water remains above freezing, thereby minimizing the risk of burst pipes and costly repairs. Additionally, using straw is a cost-effective and environmentally friendly solution for protecting Plumbing during cold weather.