Behind labor, utilities represent the largest variable cost to the hotel operator. The cost of replacing older, inefficient windows can be out of the budget and can change the architectural integrity of the building. Reduction of noise from street traffic, sirens and wind is best in class and will be the best side effect of this system to your guests. RetroWAL™ is the solution and will also eliminate street noise and protect against wind damage with an upgrade to our StormWAL™ and SoundWAL™ product lines at minimal cost.