My house is nearly a hundred years old and used to be an apartment house. The upstairs was partitioned off as one rental, while the downstairs was another. Because of this, my home has two entrances, two full bathrooms, and structure for two kitchens. It is a strange looking set up. It makes arranging furniture, plumbing and electric appliances difficult. What was truly challenging was getting a modern cooling system. The house originally had one type of air conditioner upstairs and a second one downstairs. Connecting the two AC units was not possible, and they were both old and in bad shape. It was also not feasible to implement central air conditioning. The HVAC contractor told me that air duct were not an option in our home without major construction. The walls and ceilings in the house are very old and made of plaster. Installing air ducts would ruin the house. Everything would literally crumble and fall down. We ended up investing in high velocity AC. This type of cooling uses air duct, but the air ducts are half the diameter and flexible. The air ducts are able to be carefully fitted into the walls without disturbing them. We now have one AC component that is twice as powerful. When we turn on the cooling system, we get a huge influx of cooling. In under an hour, the whole two story house is icy cold. It truly is impressive and effective. The air conditioning component was not cheap, but in the end, it was less costly than tearing down walls. The high velocity air conditioner was the only solution for the size as well as fragility of our home.